Enantioselective Synthesis of Chiral 1,4-Enynes via Palladium-Catalyzed Branch-Selective Allylic C–H Alkylation
Yazhou Lou, Zihan Lin, Chenxi Wu, Zhong‐Sheng Nong, Rui Liu, Liu‐Zhu Gong
Abstract
We herein present the construction of a chiral 1,4-enyne featuring tertiary or quaternary stereogenic center via Pd-catalyzed branch-, enantio-, and diastereoselective allylic C–H alkylation. Alkynyl carbon bearing bulky substituents appeared to exhibit competitive reaction performance, and the desired chiral 1,4-enynes were obtained in up to 93% yield and with up to >20:1 b/l, >20:1 dr, and 98% ee. A gram-scale experiment, the feasible operation of benzothiazole ring, and the preparation of the key intermediate to access (+)-Breynolide and prostaglandin are represented as a demonstration of multifarious synthetic utility in chemical synthesis.
Topics & Concepts
Enantioselective synthesisTsuji–Trost reactionPalladiumCatalysisChemistryAlkylationAllylic rearrangementCombinatorial chemistryOrganic chemistryCatalytic C–H Functionalization MethodsCatalytic Alkyne ReactionsAsymmetric Hydrogenation and Catalysis