Graduate School of Pharmaceutical Sciences and ‡Priority Organization for Innovation and Excellence, Kumamoto University , 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan.
J Org Chem. 2017 Oct 20;82(20):10968-10979. doi: 10.1021/acs.joc.7b01923. Epub 2017 Oct 6.
The domino reaction of enamines, electrophiles (N-sulfonylimines, N-tosylisocyanate, or diethyl azodicarboxylate), and trichlorosilane provided trans-amines (trans/cis = > 99:1 to 96:4). Meanwhile, the sequential imino ene-type reaction of enamines and electrophiles/NaBHCN reduction afforded cis-amines (trans/cis = 1:>99 to 15:85). The reversal of selectivity is discussed on the basis of diastereofacial selection of the plausible iminium ion intermediates. For the domino reaction of cyclic enamines and cyclic imines, high enantioselectivity (er = 95.7:4.3 to 99.9:0.1) was achieved by utilizing chiral Lewis base catalysts.
烯胺、亲电试剂(N-磺酰亚胺、N-甲苯磺酰异氰酸酯或二乙基偶氮二甲酸酯)和三氯硅烷的多米诺反应提供了反式胺(反式/顺式>99:1 至 96:4)。同时,烯胺和亲电试剂/NaBHCN 还原的顺序亚胺烯型反应得到顺式胺(反式/顺式=1:>99 至 15:85)。选择性的反转是基于可能的亚铵离子中间体的立体选择性面选择来讨论的。对于环状烯胺和环状亚胺的多米诺反应,通过使用手性路易斯碱催化剂,可以实现高对映选择性(er=95.7:4.3 至 99.9:0.1)。