β-unsaturated ketones to access various enantiomerically enriched cyclic allylic alcohols under mild conditions, catalyzed by in situ generated copper hydride ligated with (R)-DTBM-C3*-TunePhos. α-Brominated cycloalkenones were reduced with excellent enantioselectivities of up to 98% ee, while substrates that were without α-substituents were reduced chemoselectively, with moderate enantioselectivities.
我们报告了环状 α,β-不饱和酮的不对称 1,2-还原,以在温和条件下获得各种对映体富集的环状烯丙醇,由原位生成的与 ( R )-DTBM-C 3 *-TunePhos连接的氢化铜催化。α-溴化环烯酮被还原,具有高达 98% ee 的出色对映选择性,而不含 α-取代基的底物被化学选择性还原,具有中等对映选择性。
Stereospecific Overman Rearrangement of Substituted Cyclic Vinyl Bromides: Access to Fully Substituted α-Amino Ketones
作者:Álvaro Velasco-Rubio、Eric J. Alexy、Makoto Yoritate、Austin C. Wright、Brian M. Stoltz
DOI:10.1021/acs.orglett.9b03347
日期:2019.11.15
tertiary allylic amines has been developed. The vinyl bromide used to control enantioselectivity in a preceding CBS reduction is utilized as a synthetic handle for the preparation of tertiary α-amino ketones and related derivatives in an asymmetric fashion.