A redox-neutral alpha-C-H oxygenation of commercially available pyrrolidin-3-ol with a monoprotected p-quinone generated an N-aryliminium ion intermediate, which reacted in situ with boronic acid nucleophiles to produce a series of cis-2-substituted pyrrolidin-3-ols. With this strategy, 8-epi-(-)-lentiginosine was synthesized from (3R,4R)-pyrrolidine-3,4-diol in three steps.
Catalytic Enantioselective Petasis-Type Reaction of Quinolines Catalyzed by a Newly Designed Thiourea Catalyst
作者:Yousuke Yamaoka、Hideto Miyabe、Yoshiji Takemoto
DOI:10.1021/ja071470x
日期:2007.5.1
A newly designed thiourea catalyst provides sufficient activation of organoboronic acids to facilitate the enantioselective Petasis transformation of quinolines even at low temperatures. A high degree of stereocontrol was achieved in the reaction of various quinolines and organoboronic acids by using a combination of H2O and NaHCO3 as additives.
Stereoretentive trifluoromethylthiolation of (E)‑styrylboronic acid with AgSCF3 or N-trifluoromethylthiosuccinimide
作者:Changge Zheng、Mingyu Ma、Shuai Huang、Chao Jiang、Yang Liu、Yingying Fu、Kui Zhao、Ruilong Feng、Jianquan Hong