我们感谢美国国家科学基金会（CHE-1300508）和圣玛丽山大学（启动和夏季学院发展）慷慨支持这项工作。本鲁珀特（特拉华大学，质谱设施）被确认为LIFDI质谱分析鉴定。

1的异构体混合物的合成3,4,5-三甲基-2,5- heptadien -4-醇<ol><li> 填充干燥烘箱，500毫升的烧杯中，用200ml己烷中并用烘箱干燥表玻璃覆盖。 <ol><li>在一个空罩，用干净的剪刀剪下锂丝的一半英寸件。擦拭纸巾上的每个锂片以除去过量的矿物油，直至所有油似乎是从金属表面除去，并且在该含烧杯己烷放置。 </li><li>填充干燥烘箱，250毫升烧杯用100ml己烷中并用烘箱干燥表玻璃覆盖。去皮天平上此设置。 </li><li>用烘箱干燥钳，从第一烧杯除去锂丝，在一个干净的纸巾迅速擦拭以除去任何残余的油或己烷，并且转移到配衡烧杯中。直到锂丝14.0克（2.03摩尔）被加入到烧杯中重复这一过程。 </li></ol></li><li> 附加一个烘箱干燥，1升三颈烧瓶装备PED用氩气的通风橱中的流动下搅拌棒到的Schlenk线。加热枪将烧瓶几分钟，并允许它在氩气下冷却。 注意:这是使用氩气，以防止锂和二氮之间的电位反应，以形成氮化锂重要。 <ol><li>一旦冷却，用钳子迅速擦拭纸巾上的锂片，然后将锂转移到该烧瓶中在氩气逆流。 </li><li>淹没在矿物油中的任何过量的锂带进行存储。冲洗钳和剪刀与空水槽大量的水。用纸巾擦干每淹没在水中的毛巾在水槽。 注:无溶剂瓶或纸巾应水槽附近。 <ol><li>浸入已用于切割在水和地点半填充的碗锂在一个空的水槽任何纸巾或手套。在一个空罩，慢慢倒入从1.1-1.1.3口杯中的己烷成一碗含有水。添加WA之三小心入空烧杯中淬火残留的锂。 </li><li>冲洗和擦拭，其中锂被切断水的过程的其余部分继续前引擎盖。继续之前淹没在水中的这些纸巾在水槽。 </li></ol></li><li>加入约500毫升乙醚，直接从溶剂净化系统收集，通过套管转移反应烧瓶中。 </li><li>附加的烘箱中干燥回流冷凝器装有惰性气体侧臂加料漏斗和玻璃塞的三颈烧瓶中。放置一个塑料碗反应下方设置在烧瓶破裂的情况。 </li><li>添加2-溴-2-丁烯5.50g（29.0克，0.218摩尔），其已在4埃分子筛干燥过夜，以通过注射器加料漏斗。 </li><li>在5分钟的过程中添加2-溴-2-丁烯滴加大约3-4毫升，开始反应，随后回流下发生，该溶液变得浑浊。如果根10-15分钟的搅拌后，自身不会发生TLE回流，然后轻轻地用热暖烧瓶 枪，二，三分钟，直到回流下得以实现。这通常是足够的，以引发反应。 注意:即使在反应不会立即发起，控制加入2-溴-2-丁烯的关键是要保持在控制下的反应。 </li><li>添加在加料漏斗滴加90分钟的时间内将2-溴-2-丁烯的其余部分在维持整个时间周期温和回流的速率。将反应混合物将变成浅绿色。 </li><li>注射器乙酸乙酯（40.0mmol克，0.454摩尔），其已在4埃分子筛干燥过夜，和2-溴-2-丁烯（103.85克，0.782摩尔）的混合物放入加料漏斗中。该混合物添加到该反应以足够的速率，以保持在四个小时的过程中的受控但剧烈回流。 </li><li>加入完成后，注射器少量的乙酸乙酯（2.71克，0.0308摩尔）放入加料漏斗中，逐滴加入到在5分钟内将反应。该混合物将混浊橙/黄色由这些添加的结束。使反应在环境温度下搅拌过夜。 </li></ol></li><li> 第二天，替换用橡胶隔膜的加料漏斗。 <ol><li>在氩逆流，取下隔垫，用干钳抢到了一块未反应的锂。以回收尽可能多的产品成为可能，与来自洗涤瓶乙醚快速冲洗锂丝，并使溶液滴回反应容器中。然后将锂片添加到500mL烧杯充满250毫升水。 注意:锂件应单独加入到烧杯中，并在带材应该允许另一个在加入之前，充分反应。这最小化给出的淬火亲期间产生的H 2的显著量发生火灾的危险塞斯。 注:其他方法以猝灭过量的锂，如小心加入到异丙醇，也工作，但需要显著更长的时间，以充分消耗过量的锂。 </li><li> 1.3.1重复，直到所有的大块锂淬火，应要求在给定规模的60-90分钟。 </li><li>同时仍然在氩气下，加入饱和氯化铵溶液（250毫升）缓慢地滴加至搅拌的反应混合物在一小时的过程中，骤冷反应混合物和任何小块未反应锂。在反应过程中可能会轻轻地回流，并变得更加难以搅基于固体的形成。继续加入，直到沉淀的层在烧瓶底部完全溶解，形成了限定水层。 </li><li>使反应冷却30分钟后加入溶液的已完成。 </li><li>倒入烧瓶的内容到1L分液漏斗中，分离出乙醚层。 </li><li>提取用乙醚三个150毫升的部分水层。 </li><li>结合所有四个乙醚层并旋转蒸发至约75-100毫升的体积。 </li></ol></li></ol> 2. 1,2,3,4,5-五甲基环戊二烯的合成（的Cp * H） <ol><li> 附加的烘箱中干燥500mL三颈圆底烧瓶中，将惰性气体的气流下配有回流冷凝器和搅拌棒，向舒伦克线。 <ol><li>充电用对甲苯磺酸一水合物的烧瓶（8.70克，0.0457摩尔）。 </li><li>套管约50毫升乙醚到固体。 </li><li>在惰性气体下逆流，附加一个烘干的加液漏斗向反应设置。 </li><li>充电漏斗与3,4,5-三甲基-2,5- heptadien -4-醇/乙醚将来自步骤1的浓缩物。 </li><li>浓缩物滴添加到搅拌的浆料中，保持温和的回流，经1小时的过程。让反应搅拌为在加入后的额外1小时就完成了。 </li><li>将反应混合物倾入300毫升含碳酸钠4.59克（0.0433摩尔）的饱和碳酸氢钠溶液中。 </li><li>转移烧瓶的内容到1L分液漏斗中，分离出乙醚层。提取用乙醚三个100毫升的部分水层。 </li><li>结合的四个乙醚层，并用硫酸镁干燥两小时。 </li><li>过滤混合物并旋转蒸发仪下来的液体，直到〜75-100毫升物质遗存。在此阶段，该浓缩物可以存储在净身翌日过夜现有的冰箱。 </li></ol></li><li> 传送将浓缩到装有搅拌棒的烘箱中干燥，圆底烧瓶中。此烧瓶连接到配备有另一个100mL圆底烧瓶中的烘箱中干燥转移歧管。 <ol><li>酷接收瓶冰而淹没精矿在环境温度水浴中。 </li><li>适用动态真空的设置，同时搅拌该浓缩物，30〜60分钟，以除去任何残留的乙醚。 </li><li>密封该转移设置和切换浴接收烧瓶在干冰/丙酮浆液中，同时浸没在温水浴浓缩。允许陷阱到陷阱蒸馏一边搅拌，一边2-3小时的过程中，注意定期刷新真空（每15-20分钟），而浴场也超过了同一时期监测继续进行。 注:转移后，的Cp * H 39.0克（0.286摩尔，基于2-溴-2-丁烯58％）可被分离，为浅黄色油状物。 </li></ol></li></ol> 3. [*的Cp的RuCl 2] 2 29合成<ol><li> 充电钌（III）三水合物1.00克（3.95毫摩尔）的烘箱中干燥装有惰性气体上的Schlenk线流下搅拌棒100毫升的Schlenk烧瓶中。 </strong&gt;的<ol><li>套管转移50毫升甲醇中，用镁干燥，并先蒸馏来使用，在固体并搅拌30分钟。 </li><li>过滤通过一个烘箱干燥空气自由过滤漏斗在惰性气体下的溶液，充满烘箱中干燥硅藻土一英寸，向配备有搅拌棒另一个100毫升的Schlenk烧瓶中。 </li><li>除去游离的空气过滤器漏斗并用隔膜替换。 </li><li>通过注射器添加的Cp * H（1.20克，8.81毫摩尔），附加的惰性气体的气流下装有惰性气体侧臂适配器的烘箱中干燥回流冷凝器。 </li><li>密封的惰性气体的气流下在Schlenk烧瓶和回流4小时侧臂。 </li></ol></li><li> 使反应冷却和惰性气体的气流下替换用玻璃塞回流冷凝器。 <ol><li>三小时除去上的Schlenk线，真空除去溶剂，干燥。烧瓶转移到手套箱。 </li><li>手套箱内部，冲洗固体用戊烷和刮个E从烧瓶的两侧固体。过滤黑色固体到中等孔隙率玻璃料，用50ml戊烷，及干燥，真空一小时冲洗。 注意:的[Cp *的RuCl 2] 2（1.53克，基于钌的63％）被分离为深色固体。表征相匹配的文献报道。 29 </li></ol></li></ol> 4.合成的[Cp * IrCl 2] 2 30 <ol><li> 充电铱（III），氯化水合物1.00克（2.60毫摩尔）的烘箱中干燥装有惰性气体上的Schlenk线流下搅拌棒100毫升的Schlenk烧瓶中。 <ol><li>套管转移50毫升甲醇中在固体。 </li><li>通过注射器添加的Cp * H（0.50克，3.67毫摩尔），附加的惰性气体的气流下装有惰性气体侧臂适配器的烘箱中干燥回流冷凝器。 </li><li>密封的Schlenk烧瓶和回流下的惰性气体流48小时侧臂。 </li></ol></li><li&gt; 允许该反应冷却和惰性气体的气流下替换用隔膜的回流冷凝器。 <ol><li>冷却在冰浴中的烧瓶中30分钟。 </li><li>过滤通过15毫升介质的孔隙率玻璃料在空气中的反应。 </li><li>用50ml乙醚冲洗并真空干燥固体两小时。 注:的[Cp * IrCl 2] 2（1.23克，基于铱59％）分离，为橙色/红色固体。表征相匹配的文献报道。 三十 </li></ol></li></ol>

<ol>
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M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=&#951;5-pentamethylcyclopentadienyl)rhodium+and+-iridium+compounds.">&#951;5-pentamethylcyclopentadienyl)rhodium and -iridium compounds.</a> Inorg. Synth. 29, 228-234 (1992).</li><li>Andersen, R. A., Blom, R., Boncella, J. M., Burns, C. J., Volden, H. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+thermal+average+molecular+structures+of+bis(pentamethylcyclopentadienyl)magnesium(II),+-calcium(II),+and+-ytterbium(II)+in+the+gas+phase.">The thermal average molecular structures of bis(pentamethylcyclopentadienyl)magnesium(II), -calcium(II), and -ytterbium(II) in the gas phase.</a> Acta Chem. Scand. 41A, 24-35 (1987).</li><li>Gross, J. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Liquid+injection+field+desorption/ionization+of+reactive+transition+metal+complexes.">Liquid injection field desorption/ionization of reactive transition metal complexes.</a> Anal. Bioanal. Chem. 386 (1), 52-58 (2006).</li></ol>

作者什么都没有透露。

在制备heptadienol混合物，它以清洁锂发起与2-溴-2-丁烯反应之前是重要的。这是通过擦去用于纸巾存储残余的矿物油，该油出现完全从表面上除去的点，通过在己烷中的烧杯任何剩余油溶解完成。作为接收和在过程中使用前不作进一步干燥，使用了己烷。因为无论是大型反应和使用过量的锂时，通过差分法称量，以确定锂的质量是足够的。它以猝灭在发动机罩的所有材料切割和称重锂，以尽量减少继发于反应器中，包括对钳和剪刀发现任何残留的锂一火灾的危险后立即是重要的。定从计量过程剩余的锂的量小，我们发现它最安全的水迅速淬灭而不是utilizi纳克其他温和的路线。 我们集团主要用于购买商业（见材料 ）的程序锂，而是从其他供应商处购买类似的直径线仍处于可比收益率提供的Cp * H的隔离。锂线一致地使用，因为它是简单的切成片容易添加到反应容器中，仅使用剪刀。不管2-溴-2-丁烯的商业来源的，锂/卤素交换已自身一半以上的时间开始我们的小组进行反应。热风枪的用途在所有其他情况下，始终提供成功启动。 至关重要的是，以允许足够的时间以使反应引发可加成大量2-溴-2-丁烯的该混合物中之前，以确保反应保持在控制之下。看到图5a为将反应混合物的外观时引发一个代表图像。在heptadie的分离NOLS依赖于改性后处理的程序，以确保更安全和更可控的锂淬火。再次，用水锂的快速反应一直优选的其它方法，只要该锂件被允许在一段适当期间单独反应。我们的研究小组还从未有过利用控制条件下这种方法火灾。可替代地，其他的淬火方法，如使用的异丙醇，工作，但需要用于锂完全消耗显著更长的时间。在反应容器外的过量锂的这种淬火使得反应更简单的后处理，因为所有的大块金属Li的已事先在加入氯化铵溶液的反应。应当指出，一个强大的搅拌器被推荐用于此步骤（1.3.3），如直到足够的氯化铵溶液被加入以形成一个限定的水层的反应混合物可由于沉积物形成变得难以搅拌。看到<stroNG&gt;图5b和5c的细节反应淬火的典型阶段图像。 <img alt="图5" src="/files/ftp_upload/55366/55366fig5.jpg" /> 图5:（ 一 ） 用2-溴-2-丁烯锂卤素交换的起始。后饱和氯化铵溶液的50毫升已被添加（b）该heptadienol合成的淬火。 （c）该heptadienol合成的猝灭已添加250毫升饱和氯化铵溶液后。 <a href="https://ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/55366/55366fig5large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 在酸介导的环化，以形成的Cp * H（制备例2， 图6），所述heptadienols从制备1或乙醚溶液博士直接合成在进行反应之前IED使用硫酸镁已被使用，而对后续反应的产率有任何影响。这表明水在heptadienol混合物排除是不必要的环化步骤。此外，对于的Cp * H所概述纯化（ 图6b）避免了分馏。不过，从阱到阱蒸馏残留在粗物质可与来自其它的Cp * H合成保存材料组合和分馏以提供额外的纯化的配体。 <img alt="图6" src="/files/ftp_upload/55366/55366fig6.jpg" /> 图6:（ 一 ） 对于二烯醇环化反应的初始设置，形成的Cp * H。 （ 二 ）陷阱到陷阱蒸馏装置用于CP * H净化。 <a href="https://ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/55366/55366fig6large.jpg" target="_blank">请CL</a>ICK这里查看该图的放大版本。 通常在四天的过程中进行的这种方法的Cp * H的制备，与第二和第三天是最密集的。第一天包括从溶剂净化系统乙醚集合以及2-溴-2-丁烯和乙酸乙酯的原料的干燥。 2天涉及丁烯基锂的生成和随后的反应，用乙酸乙酯以制备heptadienols。 3天包围heptadienol反应后处理的酸介导的环化沿。最后一天的陷阱到陷阱蒸馏涉及的Cp * H的净化。 上述的[Cp * MCL 2] 2配合物（ 图7）的合成表明良好的收率容易的访问使用从我们的协议的Cp * H配位体的过渡金属配合物在适度的。在化合物比赛文献报道和DEM光谱数据onstrate我们的过程提供了后续metallations足够的纯度的Cp * H。虽然这些反应物上的中间规模进行，这些配合物的合成应适合于大规模制备是必要的。 <img alt="图7" src="/files/ftp_upload/55366/55366fig7.jpg" /> 图7:（1） 过滤器组件设置为3的RuCl溶液（步骤3.1.2）的隔离。 （ 二 ）初步建立反应制备的[Cp *的RuCl 2] 2（步骤3.1.5）的。 <a href="https://ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/55366/55366fig7large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 修改后的程序这里介绍访问的Cp * H上简化了反应workups和过量的锂淬火，同时提供简化的purifica中间刻度灰中的过渡金属的Cp *络合物的制备立即使用的配体。所有反应的产率是可比已知的文献程序。此协议表明值需要访问的Cp * H在相当大的数量谁希望避免使用专门的玻璃器皿或实验室设备，提供改进的切入点pentamethylcyclopentadienide金属配合物的化学研究。

由于二茂铁的20世纪50年代发现和结构鉴定，1，2，3，4环戊二烯（CP）取代配体的有机金属化学的发展起到了至关重要的作用。这些配位体都充当为一系列金属多功能辅助支撑，导致7的激活和小分子的官能化，8，9，10，11，12，13和催化异常结构和键合的研究，5，6，包括烯烃聚合。 14,15 1,2，3,4,5-五甲基环戊为（Cp *）阴离子已被证明是在过渡和主族金属的化学一特别有价值的配体，如甲基基团赋予更大的位阻保护作用，由阴离子配体增加的电子捐款，并阻止潜在的活化的环戊二烯基环。 16，17 *的Cp配体即使在今天仍然适用，作为阴离子最近被用来支持通过红外H / D交换（III），18铑，19和共轭胺化氢转移由钛介（III）。 20 我们在CP *配位体的兴趣从访问的小分子活化钴（Ⅰ）使用的反应性源的愿望茎。 21这些研究已经导致两个Cp *钴I和Cp的代*钴I L（L = N-杂环卡宾）当量用于sp 3键和SP 2 CH键氧化加成。 22，23，24作为访问我们的Cp *钴（II）的原料必要1,2,3,4,5-五甲基环戊二烯的显著数量，我们desired厘multigram合成* H，给予的实质性商务成本配体。 两个主要的方法目前存在的Cp * H，其中每个呈现固有的技术挑战的大规模制备。由标记和他的同事开发的方法包括2,3,4,5- tetramethylcyclopent -2-烯酮随后安装使用甲基锂最后甲基组成的两步​​合成。 25的合成大规模所述，使用一个12升的反应容器中，并机械搅拌，同时还要求持续的低温在0℃冷却四天。 另一种方法最初开发通过Bercaw和同事，26后来被改编马克斯27利用了原位生成烯锂为乙酸乙酯亲核攻击产生的3,4,5-三甲基-2,5- heptadien -4-醇的异构体混合物接着进行酸介导的环化，以提供的Cp * H。这种方法的初步报告是在一个大的（3-5升）的规模进行，所需的机械搅拌。此外，使用一个显著过量的锂金属的，复杂的淬火和中间heptadienols随后后处理。该过程的后续修订比例降低的反应和锂，28的量，但在反应混合物的安全淬火仍然是一个问题。由于在锂源和纯度或2-溴-2-丁烯反应物干燥度差异再现性的烯基中的锂，的启动被进一步指出的担忧。定为prepari常用程序，这些问题NG的Cp * H，看着我们发展到配体更好地获取在中间标度（30-40克），这将规避使用专业实验室玻璃器皿及设备，提高反应的重现性和安全性，并简化后处理和净化的配体。 这里，我们报告1,2,3,4,5-五甲基环戊二烯的那合成，基于由Bercaw和同事开发了现有程序的修改。配位体的经修订的合成和纯化完成上面概述的主要目标，同时允许获得良好的产率（58％）的Cp * H的大量（39克）。该过程还提供了其他额外的益处，包括生产中间heptadienols期间过量锂的更可控的骤冷和足够的纯度的Cp * H的用于与过渡金属随后金属化的简化隔离。为了证明制备的配位体的用途，它被用于合成2的[Cp * MCL 2] 2（M= IR，RU）配合。下面概述的订正协议补充现有的程序，并提供一种更简单和更容易进入点在有机金属化学的一个普遍存在的辅助配体载体的化学性质。

<table border="0" cellpadding="0" cellspacing="0" width="573">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Materials</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Lithium wire (in mineral oil)</td>
			<td style="width:71px;">Aldrich</td>
			<td>278327-100G</td>
			<td style="width:167px;">&#62;98%</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">2-bromo-2-butene (mixture of cis/trans isomers)</td>
			<td style="width:71px;">Acros</td>
			<td>200016-364&#160;&#160;</td>
			<td style="width:167px;">98%, dried over molecular sieves from an oven overnight before use</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Hexanes</td>
			<td style="width:71px;">Millipore</td>
			<td style="width:119px;">HX0299-3</td>
			<td style="width:167px;">GR ACS, used as received</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Ethyl actetate</td>
			<td style="width:71px;">Millipore</td>
			<td style="width:119px;">EX0240-3</td>
			<td style="width:167px;">GR ACS, dried over molecular sieves from an oven overnight before use</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Ammonium chloride</td>
			<td style="width:71px;">Aldrich</td>
			<td style="width:119px;">213330-2.5kg</td>
			<td style="width:167px;">ACS Reagent</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Diethyl ether</td>
			<td style="width:71px;">Millipore</td>
			<td style="width:119px;">EX0190-5</td>
			<td style="width:167px;">GR ACS, collected from a solvent purification system before use</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Magnesium sulfate</td>
			<td style="width:71px;">Aldrich</td>
			<td style="width:119px;">793612-500g</td>
			<td style="width:167px;">Anhydrous, reagent grade</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">p-toluene sulfonic acid monohydrate</td>
			<td style="width:71px;">Fisher</td>
			<td style="width:119px;">A320-500</td>
			<td style="width:167px;">ACS Certified</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Sodium bicarbonate</td>
			<td style="width:71px;">Fisher</td>
			<td style="width:119px;">5233-500</td>
			<td style="width:167px;">ACS Certified</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Sodium carbonate</td>
			<td style="width:71px;">Amresco</td>
			<td style="width:119px;">0585-500g</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Ruthenium (III) chloride trihydrate</td>
			<td style="width:71px;">Pressure Chemical</td>
			<td style="width:119px;">4750</td>
			<td style="width:167px;">40% Metal</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Iridium (III) chloride hydrate</td>
			<td style="width:71px;">Pressure Chemical</td>
			<td style="width:119px;">5730</td>
			<td style="width:167px;">53% Metal</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Methanol</td>
			<td style="width:71px;">Avantor</td>
			<td style="width:119px;">3016-22</td>
			<td style="width:167px;">AR ACS, distilled from Mg before use</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Pentane</td>
			<td style="width:71px;">J. T. Baker</td>
			<td style="width:119px;">T007-09</td>
			<td style="width:167px;">&#62;98%, dried with a solvent purification system before use</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Chloroform-d</td>
			<td style="width:71px;">Aldrich</td>
			<td style="width:119px;">151823-150G</td>
			<td style="width:167px;">99.8 atom % D</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Molecular sieves 4&#197;&#160;</td>
			<td style="width:71px;">Aldrich</td>
			<td style="width:119px;">208590-1KG</td>
			<td style="width:167px;">dried in an oven at 140 &#176;C before use&#160;</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Celite 545</td>
			<td style="width:71px;">Acros</td>
			<td style="width:119px;">AC34967-0025</td>
			<td style="width:167px;">dried in an oven at 140 &#176;C before use&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Name</td>
			<td style="width:71px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td style="width:167px;">Comments</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Equipment</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Schlenk line, with vacuum and inert gas manifolds</td>
			<td style="width:71px;">Custom</td>
			<td style="width:119px;">NA</td>
			<td>Used in Preps 1-4</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">Solvent transfer manifold</td>
			<td style="width:71px;">Chemglass</td>
			<td style="width:119px;">AF-0558-01</td>
			<td style="width:167px;">Used in 2.2</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">Airfree filter funnel</td>
			<td style="width:71px;">Chemglass</td>
			<td style="width:119px;">AF-0542-22</td>
			<td style="width:167px;">Used in 3.1.3</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;">Glovebox</td>
			<td style="width:71px;">Vacuum Atmospheres</td>
			<td style="width:119px;">OMNI</td>
			<td style="width:167px;">Used in 3.2.2</td>
		</tr>
	</tbody>
</table>

accessing valuable ligand supports for transition metals: a modified, intermediate scale preparation of 1,2,3,4,5-pentamethylcyclopentadiene

1,2,3,4,5-五甲基环戊二烯为（Cp * H）的一个可靠的，中间规模制备提出的基础上，从初始2-溴-2-丁烯锂化，随后通过酸介导的二烯醇环化派生现有协议的修改。配位体的经修订的合成和纯化避免使用机械搅拌的同时仍允许访问以良好的收率（58％）的Cp * H的显著量（39克）。该过程还提供了其他额外的益处，包括生产中间heptadienols期间过量锂的更可控的骤冷和足够的纯度的Cp * H的用于与过渡金属金属取代的简化隔离。该配体随后被用于合成的[Cp * MCL 2] 2配合物既铱和钌的证明* H制备和由我们的方法纯化的Cp的效用。本文介绍的步骤提供了一个无所不在的辅助配体燮得以大量端口中的有机金属化学中使用，同时减少对专门的实验室设备的需要，从而提供了一种更简单和更方便入口点1,2,3,4,5-五甲基环戊二烯的化学。

上述的Cp * H合成所述的协议依赖于三个步骤过程通过Bercaw和同事开发和商标改性（ 图1）的变形例。空气敏感烯基锂在原位通过锂/卤素交换反应而制备由顺式和反式 -2-丁烯的混合物，随后用乙酸乙酯淬灭以制备heptadienols的异构体混合物。该混合物可以不经进一步纯化即可使用的酸介导的环化，以提供单所需产物中，Cp * H。 <img alt="图1" src="/files/ftp_upload/55366/55366fig1.jpg" /> 图 1: 在所描述的协议利用的Cp * H合成的合成方案。 <a href="https://ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/55366/55366fig1large.jpg" target="_blank">请点击这里查看</a><html>更大的版本这个数字。 与上述我们的过程中，Cp * H可始终如一地在纯度足以用于与中期直接金属化反应随后使用良好的产率（50-60％）中分离到后过渡金属或在制备主要组pentamethylcyclopentadienide盐。 31代表1 H和13 C NMR谱，记录在CDCl 3中，所述的Cp * H通过上文概述的陷阱到阱蒸馏纯化的在图2中提供。 <img alt="图2" src="/files/ftp_upload/55366/55366fig2.jpg" /> 图2:在25℃的Cp * H记录在CDCl 3中（a）的1 H NMR谱。 （ 二 ）。13 C NMR Cp的光谱* H在25℃下记录在CDCl 3中。S / ftp_upload / 55366 / 55366fig2large.jpg"目标="_空白"&gt;点击此处查看该图的放大版本。 为了演示的Cp * H的由协议产生的效用，使用配位体制备两种过渡金属配合物。桥接钌（III）卤化物，混合[Cp *的RuCl 2] 2，在适中的产率（63％）通过回流的Cp * H与钌（III）的甲醇（ 图3a）三水合物是合成的。空气敏感产物在手套箱中分离，并随后在惰性气氛下特征。顺磁性产物的1 H NMR谱匹配的文献报告（ 图3b）。该复合物的身份由高分辨率液体注入场解析电离（LIFDI）的氯仿32质谱进一步确认，表示所希望的二聚体成功制备。 图3:（a）对在所描述的方案采用的[Cp *的RuCl 2] 2的合成。 （ 二 ）的[Cp *的RuCl 2] 2在25℃下记录在CDCl 3中1 H NMR谱。 <a href="https://ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/55366/55366fig3large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 桥接合铱（III）的卤化物，混合[Cp * IrCl 2] 2，也是在适中的产率（59％）通过回流用铱（III），氯化水合物（ 图4a）的Cp * H制备。空气稳定的产品被查出的台式和随后表征。的1 H和反磁性产品的13 C NMR谱匹配的以前的报告（ 图第4B和4C）。该复合物的nuclearity进一步通过高分辨率LIFDI质谱氯仿确认，指示准备所需的二聚体组成。 <img alt="图4" src="/files/ftp_upload/55366/55366fig4.jpg" /> 图4:（a）对在所描述的方案采用的[Cp * IrCl 2] 2的合成。 （ 二 ）的[Cp * IrCl 2] 2在25℃下记录在CDCl 3中1 H NMR谱。 （ 三 ）。13 C NMR的的[Cp * IrCl 2] 2在25℃下记录在CDCl 3中的频谱。 <a href="https://ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/55366/55366fig4large.jpg" target="_blank">请点击此处查看该图的放大版本。</a>

Watch this Scientific Journal Video about Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene at JoVE.com

Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene

1,2,3,4,5-五甲基环戊二烯（的Cp * H）的可靠，中间规模制备呈现。为配位体的合成和纯化的订正协议最小化了专门的实验室设备的需要，同时简化反应workups和产物纯化。的Cp * H中的[Cp * MCL 2]的合成中的应用也被描述2复合物（M =钌，铱）。

访问有价值的配体为支持过渡金属:1,2,3,4,5-五甲基环戊二烯的一种改进，中级规模制备

A reliable, intermediate scale preparation of 1,2,3,4,5-pentamethylcyclopentadiene (Cp*H) is presented, based on modifications of existing protocols that ...

accessing-valuable-ligand-supports-for-transition-metals-modified

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Organic Chemistry

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Unit 1

Reactions of Alkenes

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10.3K 次观看.  Mount St. Mary's University.  1,2,3,4,5-五甲基环戊二烯（的Cp * H）的可靠，中间规模制备呈现。为配位体的合成和纯化的订正协议最小化了专门的实验室设备的需要，同时简化反应workups和产物纯化。的Cp * H中的[Cp * MCL 2]的合成中的应用也被描述2复合物（M =钌，铱）。 

视频: Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene

Transport of Surface-modified Carbon Nanotubes through a Soil Column

Carbon nanotubes (CNTs) are widely manufactured nanoparticles, which are being utilized in a number of consumer products, such as sporting goods, electronics and biomedical applications. Due to their accelerating production and use, CNTs constitute a potential environmental risk if they are released to soil and groundwater systems. It is therefore essential to improve the current understanding of environmental fate and transport of CNTs. The transport and retention of CNTs in both natural and artificial media have been reported in literature, but the findings widely vary and are thus not conclusive. There are a number of physical and chemical parameters responsible for variation in retention and transport. In this study, a complete procedure of selected multiwalled carbon nanotubes (MWCNTs) is presented starting from their surface modification to a complete set of laboratory column experiments at critical physical and chemical scenarios. Results indicate that the stability of the commercially available MWCNTs are critical with their attached surface functional group which can also influence the transport and retention of MWCNT through the surrounding medium.

Surface properties of a nanoparticle are important for their interaction with the surrounding medium. Therefore the surface modification of carbon nanotubes can be critical for their transport and retention through porous media. Here, lab scale column experiments are used to understand the possible transport and retention of these nanoparticles.

表面修饰碳纳米管通过土柱运输

Carbon nanotubes (CNTs) are widely manufactured nanoparticles, which are being utilized in a number of consumer products, such as sporting goods, ...

科研

化学

Preparation of Mica and Silicon Substrates for DNA Origami Analysis and Experimentation

The designed nature and controlled, one-pot synthesis of DNA origami provides exciting opportunities in many fields, particularly nanoelectronics. Many of these applications require interaction with and adhesion of DNA nanostructures to a substrate. Due to its atomically flat and easily cleaned nature, mica has been the substrate of choice for DNA origami experiments. However, the practical applications of mica are relatively limited compared to those of semiconductor substrates. For this reason, a straightforward, stable, and repeatable process for DNA origami adhesion on derivatized silicon oxide is presented here. To promote the adhesion of DNA nanostructures to silicon oxide surface, a self-assembled monolayer of 3-aminopropyltriethoxysilane (APTES) is deposited from an aqueous solution that is compatible with many photoresists. The substrate must be cleaned of all organic and metal contaminants using Radio Corporation of America (RCA) cleaning processes and the native oxide layer must be etched to ensure a flat, functionalizable surface. Cleanrooms are equipped with facilities for silicon cleaning, however many components of DNA origami buffers and solutions are often not allowed in them due to contamination concerns. This manuscript describes the set-up and protocol for in-lab, small-scale silicon cleaning for researchers who do not have access to a cleanroom or would like to incorporate processes that could cause contamination of a cleanroom CMOS clean bench. Additionally, variables for regulating coverage are discussed and how to recognize and avoid common sample preparation problems is described.

Reproducible cleaning processes for substrates used in DNA origami research are described, including bench-top RCA cleaning and derivatization of silicon oxide. Protocols for surface preparation, DNA origami deposition, drying parameters, and simple experimental set-ups are illustrated.

对于DNA折纸分析和实验准备云母和硅衬底

The designed nature and controlled, one-pot synthesis of DNA origami provides exciting opportunities in many fields, particularly nanoelectronics. Many of ...

Synthesis of Ligand-free CdS Nanoparticles within a Sulfur Copolymer Matrix

Aliphatic ligands are typically used during the synthesis of nanoparticles to help mediate their growth in addition to operating as high-temperature solvents. These coordinating ligands help solubilize and stabilize the nanoparticles while in solution, and can influence the resulting size and reactivity of the nanoparticles during their formation. Despite the ubiquity of using ligands during synthesis, the presence of aliphatic ligands on the nanoparticle surface can result in a number of problems during the end use of the nanoparticles, necessitating further ligand stripping or ligand exchange procedures. We have developed a way to synthesize cadmium sulfide (CdS) nanoparticles using a unique sulfur copolymer. This sulfur copolymer is primarily composed of elemental sulfur, which is a cheap and abundant material. The sulfur copolymer has the advantages of operating both as a high temperature solvent and as a sulfur source, which can react with a cadmium precursor during nanoparticle synthesis, resulting in the generation of ligand free CdS. During the reaction, only some of the copolymer is consumed to produce CdS, while the rest remains in the polymeric state, thereby producing a nanocomposite material. Once the reaction is finished, the copolymer stabilizes the nanoparticles within a solid polymeric matrix. The copolymer can then be removed before the nanoparticles are used, which produces nanoparticles that do not have organic coordinating ligands. This nascent synthesis technique presents a method to produce metal-sulfide nanoparticles for a wide variety of applications where the presence of organic ligands is not desired.

Herein we present a method to synthesize ligand-free cadmium sulfide (CdS) nanoparticles based on a unique sulfur copolymer. The sulfur copolymer operates as a high temperature solvent and a sulfur source during the nanoparticle synthesis and stabilizes the nanoparticles after the reaction.

a硫磺共聚物基质内的免费配体硫化镉纳米粒子的合成

Aliphatic ligands are typically used during the synthesis of nanoparticles to help mediate their growth in addition to operating as high-temperature ...

Sulfate Separation by Selective Crystallization with a Bis-iminoguanidinium Ligand

A simple and effective method for selective sulfate separation from aqueous solutions by crystallization with a bis-guanidinium ligand, 1,4-benzene-bis(iminoguanidinium) (BBIG), is demonstrated. The ligand is synthesized as the chloride salt (BBIG-Cl) by in situ imine condensation of terephthalaldehyde with aminoguanidinium chloride in water, followed by crystallization as the sulfate salt (BBIG-SO4). Alternatively, BBIG-Cl is synthesized ex situ in larger scale from ethanol. The sulfate separation ability of the BBIG ligand is demonstrated by selective and quantitative crystallization of sulfate from seawater. The ligand can be recycled by neutralization of BBIG-SO4 with aqueous NaOH and crystallization of the neutral bis-iminoguanidine, which can be converted back into BBIG-Cl with aqueous HCl and reused in another separation cycle. Finally, 35S-labeled sulfate and &#946; liquid scintillation counting are employed for monitoring the sulfate concentration in solution. Overall, this protocol will instruct the user in the necessary skills to synthesize a ligand, employ it in the selective crystallization of sulfate from aqueous solutions, and quantify the separation efficiency.

A protocol for in situ aqueous synthesis of a bis(iminoguanidinium) ligand and its utilization in selective separation of sulfate is presented.

分离硫酸选择性结晶用双 -  iminoguanidinium配体

A simple and effective method for selective sulfate separation from aqueous solutions by crystallization with a bis-guanidinium ligand, ...

Preparation and Evaluation of 99mTc-labeled Tridentate Chelates for Pre-targeting Using Bioorthogonal Chemistry

Pre-targeting combined with bioorthogonal chemistry is emerging as an effective way to create new radiopharmaceuticals. Of the methods available, the inverse electron demand Diels-Alder (IEDDA) cycloaddition between a radiolabeled tetrazines and trans-cyclooctene (TCO) linked to a biomolecule has proven to be a highly effective bioorthogonal approach to imaging specific biological targets. Despite the fact that technetium-99m remains the most widely used isotope in diagnostic nuclear medicine, there is a scarcity of methods for preparing 99mTc-labeled tetrazines. Herein we report the preparation of a family of tridentate-chelate-tetrazine derivatives and their Tc(I) complexes. These hitherto unknown compounds were radiolabeled with 99mTc using a microwave-assisted method in 31% to 83% radiochemical yield. The products are stable in saline and PBS and react rapidly with TCO derivatives in vitro. Their in vivo pre-targeting abilities were demonstrated using a TCO-bisphosphonate (TCO-BP) derivative that localizes to regions of active bone metabolism or injury. In murine studies, the 99mTc-tetrazines showed high activity concentrations in knees and shoulder joints, which was not observed when experiments were performed in the absence of TCO-BP. The overall uptake in non-target organs and pharmacokinetics varied greatly depending on the nature of the linker and polarity of the chelate.

Preparation and Evaluation of 99mTc-labeled Tridentate Chelates for Pre-targeting Using Bioorthogonal Chemistry

Here, we describe a protocol for radiolabeling and in vivo testing of tridentate 99mTc(I) chelate-tetrazine derivatives for pre-targeting and bioorthogonal chemistry.

制备和评价<sup&gt;99米</sup&gt;锝标记的三齿螯合物预靶向使用生物正交化学

Pre-targeting combined with bioorthogonal chemistry is emerging as an effective way to create new radiopharmaceuticals. Of the methods available, the ...

Deposition of Porous Sorbents on Fabric Supports

A microwave deposition technique for silanes, previously described for production of oleophobic fabrics, is adapted to provide a fabric support material that can be subsequently treated by dip coating. Dip coating with a sol preparation provides a supported porous layer on the fabric. In this case, the porous layer is a porphyrin functionalized sorbent system based on a powdered material that has been demonstrated previously for the capture and conversion of phosgene. A representative coating is applied to cotton fabric at a loading level of 10 mg/g. This coating has minimal impact on water vapor transport through the fabric (93% of the support fabric rate) while significantly reducing transport of 2-chloroethyl ethyl sulfide (CEES) through the material (7% of support fabric rate). The described approaches are suitable for use with other fabrics providing amine and hydroxyl groups for modification and can be used in combination with other sol preparations to produce varying functionality.

This report details a microwave-initiated approach for deposition of porphyrin functionalized porous organosilicate sorbents on a cotton fabric and demonstrates reduction in 2-chloroethyl ethyl sulfide (CEES) transport through the fabric resulting from this treatment.

织物支架上多孔吸附剂的沉积

A microwave deposition technique for silanes, previously described for production of oleophobic fabrics, is adapted to provide a fabric support material ...

Synthesis and Performance Characterizations of Transition Metal Single Atom Catalyst for Electrochemical CO2 Reduction

This protocol presents both the synthesis method of the Ni single atom catalyst, and the electrochemical testing of its catalytic activity and selectivity in aqueous CO2 reduction. Different from traditional metal nanocrystals, the synthesis of metal single atoms involves a matrix material that can confine those single atoms and prevent them from aggregation. We report an electrospinning and thermal annealing method to prepare Ni single atoms dispersed and coordinated in a graphene shell, as active centers for CO2 reduction to CO. During the synthesis, N dopants play a critical role in generating graphene vacancies to trap Ni atoms. Aberration-corrected scanning transmission electron microscopy and three-dimensional atom probe tomography were employed to identify the single Ni atomic sites in graphene vacancies. Detailed setup of electrochemical CO2 reduction apparatus coupled with an on-line gas chromatography is also demonstrated. Compared to metallic Ni, Ni single atom catalyst exhibit dramatically improved CO2 reduction and suppressed H2 evolution side reaction.

Synthesis and Performance Characterizations of Transition Metal Single Atom Catalyst for Electrochemical CO2 Reduction

Here, we present a protocol for the synthesis and electrochemical testing of transition metal single atoms coordinated in graphene vacancies as active centers for selective carbon dioxide reduction to carbon monoxide in aqueous solutions.

电化学 CO2还原的过渡金属单原子催化剂的合成及性能表征

This protocol presents both the synthesis method of the Ni single atom catalyst, and the electrochemical testing of its catalytic activity and selectivity ...

Ligand-Mediated Nucleation and Growth of Palladium Metal Nanoparticles

The size, size distribution and stability of colloidal nanoparticles are greatly affected by the presence of capping ligands. Despite the key contribution of capping ligands during the synthesis reaction, their role in regulating the nucleation and growth rates of colloidal nanoparticles is not well understood. In this work, we demonstrate a mechanistic investigation of the role of trioctylphosphine (TOP) in Pd nanoparticles in different solvents (toluene and pyridine) using in situ SAXS and ligand-based kinetic modeling. Our results under different synthetic conditions reveal the overlap of nucleation and growth of Pd nanoparticles during the reaction, which contradicts the LaMer-type nucleation and growth model. The model accounts for the kinetics of Pd-TOP binding for both, the precursor and the particle surface, which is essential to capture the size evolution as well as the concentration of particles in situ. In addition, we illustrate the predictive power of our ligand-based model through designing the synthetic conditions to obtain nanoparticles with desired sizes. The proposed methodology can be applied to other synthesis systems and therefore serves as an effective strategy for predictive synthesis of colloidal nanoparticles.

The main goal of this work is to elucidate the role of capping agents in regulating the size of palladium nanoparticles by combining in situ small angle x-ray scattering (SAXS) and ligand-based kinetic modeling.

配体介导成核与钯金属纳米粒子的生长

The size, size distribution and stability of colloidal nanoparticles are greatly affected by the presence of capping ligands. Despite the key contribution ...

Microfluidic Preparation of Liquid Crystalline Elastomer Actuators

This paper focuses on the microfluidic process (and its parameters) to prepare actuating particles from liquid crystalline elastomers. The preparation usually consists in the formation of droplets containing low molar mass liquid crystals at elevated temperatures. Subsequently, these particle precursors are oriented in the flow field of the capillary and solidified by a crosslinking polymerization, which produces the final actuating particles. The optimization of the process is necessary to obtain the actuating particles and the proper variation of the process parameters (temperature and flow rate) and allows variations of size and shape (from oblate to strongly prolate morphologies) as well as the magnitude of actuation. In addition, it is possible to vary the type of actuation from elongation to contraction depending on the director profile induced to the droplets during the flow in the capillary, which again depends on the microfluidic process and its parameters. Furthermore, particles of more complex shapes, like core-shell structures or Janus particles, can be prepared by adjusting the setup. By the variation of the chemical structure and the mode of crosslinking (solidification) of the liquid crystalline elastomer, it is also possible to prepare actuating particles triggered by heat or UV-vis irradiation.

This article describes the microfluidic process and parameters to prepare actuating particles from liquid crystalline elastomers. This process allows the preparation of actuating particles and the variation of their size and shape (from oblate to strongly prolate, core-shell, and Janus morphologies) as well as the magnitude of actuation.

液晶弹性体致动器的微流控制备

This paper focuses on the microfluidic process (and its parameters) to prepare actuating particles from liquid crystalline elastomers. The preparation ...

Gold Nanoparticle Modified Carbon Fiber Microelectrodes for Enhanced Neurochemical Detection

For over 30 years, carbon-fiber microelectrodes (CFMEs) have been the standard for neurotransmitter detection. Generally, carbon fibers are aspirated into glass capillaries, pulled to a fine taper, and then sealed using an epoxy to create electrode materials that are used for fast scan cyclic voltammetry testing. The use of bare CFMEs has several limitations, though. First and foremost, the carbon fiber contains mostly basal plane carbon, which has a relatively low surface area and yields lower sensitivities than other nanomaterials. Furthermore, the graphitic carbon is limited by its temporal resolution, and its relatively low conductivity. Lastly, neurochemicals and macromolecules have been known to foul at the surface of carbon electrodes where they form non-conductive polymers that block further neurotransmitter adsorption. For this study, we modify CFMEs with gold nanoparticles to enhance neurochemical testing with fast scan cyclic voltammetry. Au3+ was electrodeposited or dipcoated from a colloidal solution onto the surface of CFMEs. Since gold is a stable and relatively inert metal, it is an ideal electrode material for analytical measurements of neurochemicals. Gold nanoparticle modified (AuNP-CFMEs) had a stability to dopamine response for over 4 h. Moreover, AuNP-CFMEs exhibit an increased sensitivity (higher peak oxidative current of the cyclic voltammograms) and faster electron transfer kinetics (lower &#916;EP or peak separation) than bare unmodified CFMEs. The development of AuNP-CFMEs provides the creation of novel electrochemical sensors for detecting fast changes in dopamine concentration and other neurochemicals at lower limits of detection. This work has vast applications for the enhancement of neurochemical measurements. The generation of gold nanoparticle modified CFMEs will be vitally important for the development of novel electrode sensors to detect neurotransmitters in vivo in rodent and other models to study neurochemical effects of drug abuse, depression, stroke, ischemia, and other behavioral and disease states.

In this study, we modify carbon-fiber microelectrodes with gold nanoparticles to enhance the sensitivity of neurotransmitter detection.

用于增强神经化学检测的金纳米粒子改性碳纤维微电极

For over 30 years, carbon-fiber microelectrodes (CFMEs) have been the standard for neurotransmitter detection. Generally, carbon fibers are aspirated into ...