Rhodium-Catalyzed Enantioselective 1,6-Addition of Arylboronic Acids to Enynamides: Asymmetric Synthesis of Axially Chiral Allenylsilanes
摘要:
Rhodium-catalyzed asymmetric 1,6-addition of arylboronic acids to beta-alkynyl acrylamides substituted with a silyl group on the alkyne terminus took place to give high yields of axially chiral allenylsilanes with 94-99% enantioselectivity, which was realized by use of a rhodium/chiral diene complex.
Highly Stereoselective Synthesis of α-Alkyl-α-Hydroxycarboxylic Acid Derivatives Catalyzed by a Dinuclear Zinc Complex
作者:Barry M. Trost、Keiichi Hirano
DOI:10.1002/anie.201201116
日期:2012.6.25
dinuclear zinc–ProPhenol catalyst enables highly enantioselective nitro‐Michael reactions with oxazol‐4(5H)‐ones as nucleophilic substrates (see scheme, Nap=2‐naphthyl). This work highlights the utility of the ProPhenol family of ligands. The modular nature of these ligands proved crucial in the optimization of reaction conditions to achieve excellent stereoselectivities.