Kondoh Azusa, Terada Masahiro
Research and Analytical Center for Giant Molecules, Graduate School of Science, Tohoku University, Aramaki, Aoba-ku, Sendai, 980-8578, Japan.
Department of Chemistry, Graduate School of Science, Tohoku University, Aramaki, Aoba-ku, Sendai, 980-8578, Japan.
Chemistry. 2018 Mar 15;24(16):3998-4001. doi: 10.1002/chem.201800219. Epub 2018 Feb 16.
A novel "umpolung" intramolecular cyclization of alkynyl imines, in which the electrophilic imine sp -carbon formally serves as a nucleophilic site, was developed under Brønsted base catalysis. The reaction involves the unprecedented catalytic generation of α-aminoester enolates from α-iminoesters via the 1,2-addition of the anion of a secondary phosphite to an imine moiety followed by the [1,2]-rearrangement of a dialkoxyphosphoryl moiety from carbon to nitrogen, which is a formal umpolung process, and the intramolecular addition to an alkyne. This is a rare example of a [1,2]-rearrangement of a dialkoxyphosphoryl moiety from carbon to nitrogen to generate an α-amino carbanion and the first catalytic carbon-carbon bond forming reaction utilizing the resulting carbanion as a nucleophile.
在布朗斯台德碱催化下，开发了一种新型的炔基亚胺“极性翻转”分子内环化反应，其中亲电亚胺sp -碳正式作为亲核位点。该反应涉及通过亚磷酸酯阴离子与亚胺部分的1,2-加成，然后将二烷氧基磷酰基部分从碳到氮进行[1,2]-重排（这是一个形式上的极性翻转过程），从α-亚胺酯前所未有的催化生成α-氨基酯烯醇盐，以及分子内与炔烃的加成。这是二烷氧基磷酰基部分从碳到氮进行[1,2]-重排以生成α-氨基碳负离子的罕见例子，也是利用所得碳负离子作为亲核试剂的首个催化碳-碳键形成反应。
