Asymmetric Synthesis of Deoxypropionate Derivatives via Catalytic Hydrogenolysis of Enantioenriched Z-Ketene Heterodimers
摘要:
A diagterosetective approach to deoxypropionate derivatives through Pd/C-catalyted hydrogenolysis of enantio enriched ketene heterodimers is described. Catalytic hydrogenolysis of the Z-isomer of ketene heterodimers facilitates access to, anti-deoxypropionate derivatives (10 examples With dr 7:1 to >20:1). Transfer of chirality from the Z-ketene heterodimer to an acid product was good to excellent in most as (78-99% ee for 12 examples).
Mechanistic Investigations of the Pd‐Catalyzed Hydrogenolysis of Ketene Heterodimer β‐Lactones
作者:Manashi Panda、Mukulesh Mondal、Shi Chen、Ahmad A. Ibrahim、Dylan J. Twardy、Nessan J. Kerrigan
DOI:10.1002/ejoc.202000976
日期:2020.9.22
Catalytic hydrogenolysis of the Z‐isomer of a series of aryl‐substituted ketene heterodimers facilitated access to deoxypropionate derivatives, favoring the anti‐isomer, and with excellent transfer of chirality. Anti‐β‐elimination and an anti‐selective hydrogenation of an E‐olefin intermediate are proposed to be key steps.
Catalytic Asymmetric Heterodimerization of Ketenes
作者:Ahmad A. Ibrahim、Divya Nalla、Maxwell Van Raaphorst、Nessan J. Kerrigan
DOI:10.1021/ja211678m
日期:2012.2.15
In this Communication we describe an unprecedented catalytic asymmetric heterodimerization of ketenes of wide substrate scope. The alkaloid-catalyzed method provides access to ketene heterodimer beta-lactones and allows even two different monosubstituted ketenes to be cross-dimerized, with excellent enantioselectivity (17 examples with >= 90% ee) and excellent heterodimer regioselectivity observed in all cases.