We have successfully developed the asymmetric hydrogenation of β‐silyl‐α,β‐unsaturatedesters to prepare chiral 3‐substituted‐3‐silylpropionic esterproducts catalyzed by rhodium/bisphosphine‐thiourea (ZhaoPhos) with excellent results (up to 97% yield, >99% ee, 1500 TON). Moreover, our hydrogenation products can be efficiently converted to other important organic molecules, such as chiral ethyl (R
A ruthenium-catalyzed [1,2]-Brook rearrangement involved dominosequence is presented to prepare highly functionalized silyloxy indenes with atomic- and step-economy. This domino reaction is triggered by acylsilane-directed C–H activation, and the aldehyde controlled the subsequent enol cyclization/Brook Rearrangement other than β–H elimination. The protocol tolerates a broad substitution pattern,
作者:Jiawei Rong、Rik Oost、Alaric Desmarchelier、Adriaan J. Minnaard、Syuzanna R. Harutyunyan
DOI:10.1002/anie.201409815
日期:2015.3.2
reagents to acylsilanes is catalyzed by copper diphosphine complexes. This transformation affords α‐silylated tertiary alcohols in up to 97 % yield and 98:2 enantiomeric ratio. The competing Meerwein–Ponndorf–Verley reduction is suppressed by the use of a mixture of Lewis acid additives. The chiral catalyst can be recovered as a copper complex and used repeatedly without any loss of catalytic activity
Trimethylsilylmethyl ketones, readily from acyl chlorides, undergo a Reformatsky—Peterson reaction sequence to give 3-alkenoates regioselectivity. Acylsilanes, however, react with either zinc ester enolates or trimethylsilymethylmagnesium chloride to give the corresponding tertiary alcohols which, depending on their structure, spontaneously undergo either elimination or a Brook rearrangement—Peterson