Tethering strategies in alkynylamino carbene complexes
摘要:
During the synthesis of complex cyclic macromolecular structures, the reaction of different mono- di- and triamino alkynyl metal carbene systems with primary and secondary amines was studied. The results showed the low stability of the metal carbene complexes obtained from the conjugate addition of primary amines in contrast to the fairly good stability of the corresponding complexes obtained from the addition of secondary amines. (C) 2001 Elsevier Science B.V. All rights reserved.
ESI-MS研究了一系列芳基,烯基和炔基(Fischer)氨基碳烯络合物的电离作用。该过程需要从ESI源中初步捕获一个电子,然后将氢原子转移到添加剂(TTF或Cs 2 CO 3)上。不论其结构如何,只要NH和N,N-二取代氨基碳烯都具有可提取的H原子,它们就可以在ESI-MS条件下有效地电离。总的来说,该过程可以设想为单电子转移-H原子转移过程。实验结果得到DFT计算的支持。双炔基氨基碳烯配合物的ESI-MS电离遵循相同的模式。但是,[M-H] -离子通过芳基乙炔挤出以及通常的CO损失序列而释放出来。该过程需要存在一个游离的NH基团,并且是通过分子内氢从NH到金属中心的转移而发生的。在氮原子之间具有刚性束缚或缺少游离NH基的双氨基卡宾不会产生这种断裂。