Highly enantioselective 1,4-addition of arylzinc reagents to 3-arylpropenals catalyzed by a rhodium–binap complex in the presence of chlorotrimethylsilane
摘要:
Asymmetric 1,4-addition of arylzinc chlorides to (E)-3-arylpropenals proceeded with high enantioselectivity in the presence of a rhodium/(R)-binap catalyst and chlorotrimethylsilane to give, after hydrolysis, high yields of the corresponding 3.3-diarylpropanals of 98-99% ee. The presence of the chlorosilane is essential for high yields of the 1,4-addition products. (c) 2006 Elsevier Ltd. All rights reserved.
Highly enantioselective 1,4-addition of arylzinc reagents to 3-arylpropenals catalyzed by a rhodium–binap complex in the presence of chlorotrimethylsilane
摘要:
Asymmetric 1,4-addition of arylzinc chlorides to (E)-3-arylpropenals proceeded with high enantioselectivity in the presence of a rhodium/(R)-binap catalyst and chlorotrimethylsilane to give, after hydrolysis, high yields of the corresponding 3.3-diarylpropanals of 98-99% ee. The presence of the chlorosilane is essential for high yields of the 1,4-addition products. (c) 2006 Elsevier Ltd. All rights reserved.
Chiral dihydrobenzo[1,4]oxazines as catalysts for the asymmetric transfer-hydrogenation of α,β-unsaturated aldehydes
作者:Christian Ebner、Andreas Pfaltz
DOI:10.1016/j.tet.2011.10.051
日期:2011.12
A new class of organocatalysts based on the structure of 2,3-dihydrobenzo[1,4]oxazine was prepared and applied in the enantioselective transfer-hydrogenation of α,β-unsaturatedaldehydes with Hantzsch ester as hydride donor. These catalysts proved to be particularly effective for the conjugate reduction of β,β-diaryl-substituted acrylaldehydes leading to saturated aldehydes bearing a stereogenic center
Enantiospecific cross-coupling of cyclic alkyl sulfones
作者:Roberto Nolla-Saltiel、Zachary T. Ariki、Stefanie Schiele、Jana Alpin、Yasuyo Tahara、Daisuke Yokogawa、Masakazu Nambo、Cathleen M. Crudden
DOI:10.1038/s41557-024-01594-x
日期:2024.9
entantioconvergent cross-couplings. The high acidity of sulfones makes it unclear whether this transformation is even possible outside tertiary systems. Here we report the enantiospecific cross-coupling of cyclic sulfones and Grignardreagents. Up to 99% chirality transfer is observed despite the strong basicity of the Grignard components. In situ monitoring reveals that the cross-coupling is kinetically