Diastereoselective Friedel–Crafts Alkylation of Hydronaphthalenes
摘要:
An efficient and versatile synthesis of chiral tetralins has been developed using both inter- and intra-molecular Friedel Crafts alkylation as a key step. The readily available hydronaphthalene substrates were prepared via a highly enantioselective metal-catalyzed ring opening of meso-oxabicyclic alkenes followed by hydrogenation. A wide variety of complex tetracyclic compounds have been isolated with high levels of regio-, diastereo-, and enantioselectivity.
An efficient and versatile synthesis of chiral tetralins has been developed using both inter- and intra-molecular Friedel Crafts alkylation as a key step. The readily available hydronaphthalene substrates were prepared via a highly enantioselective metal-catalyzed ring opening of meso-oxabicyclic alkenes followed by hydrogenation. A wide variety of complex tetracyclic compounds have been isolated with high levels of regio-, diastereo-, and enantioselectivity.
Organocatalytic Synthesis of α-Trifluoromethyl Allylboronic Acids by Enantioselective 1,2-Borotropic Migration
作者:Sybrand J. T. Jonker、Ramasamy Jayarajan、Tautvydas Kireilis、Marie Deliaval、Lars Eriksson、Kálmán J. Szabó
DOI:10.1021/jacs.0c09923
日期:2020.12.23
Chiral α-substituted allylboronic acids were synthesized by asymmetric homologation of alkenylboronic acids using CF3/TMS-diazomethanes in the presence of BINOLcatalyst and ethanol. The chiral α-substituted allylboronic acids were reacted with aldehydes or oxidized to alcohols in situ with a high degree of chirality transfer. The oxygen-sensitive allylboronic acids can be purified via their isolated