NH-type of chiral Ni(ii) complexes of glycine Schiff base: design, structural evaluation, reactivity and synthetic applications
作者:Mackenzie Bergagnini、Kazunobu Fukushi、Jianlin Han、Norio Shibata、Christian Roussel、Trevor K. Ellis、José Luis Aceña、Vadim A. Soloshonok
DOI:10.1039/c3ob41959b
日期:——
of “N–H” Ni(II) complexes of glycineSchiffbases and study general aspects of their reactivity. It was confirmed that the presence of NH function in these Ni(II) complexes does not interfere with the homologation of the glycine residue, rendering these derivatives of high synthetic value for the general synthesis of α-amino acids. In particular, the practical application of these NH-type complexes was
Application of modular nucleophilic glycine equivalents for truly practical asymmetric synthesis of β-substituted pyroglutamic acids
作者:Vadim A. Soloshonok、Hisanori Ueki、Trevor K. Ellis、Takeshi Yamada、Yasufumi Ohfune
DOI:10.1016/j.tetlet.2004.12.093
日期:2005.2
A new series of achiral glycine equivalents have been evaluated with respect to their synthetic utility for the production of beta-substituted pyroglutamic acid derivatives. Among them, the piperidine-de rived complex was found to be a superior glycine derivative for the Michael additions with various (R)-N-(E-enoyl)-4-phenyl-1,3-oxazolidin-2-ones representing a general and practical synthesis of sterically constrained beta-substituted pyroglutamic acids. In particular, application of complex allowed for the first time preparation of the corresponding isopropyl derivatives thus increasing the synthetic efficiency and expanding generality these Michael addition reactions. (C) 2004 Elsevier Ltd. All rights reserved.