The influence of reaction conditions on the Diels–Alder cycloadditions of 2-thio-3-chloroacrylamides; investigation of thermal, catalytic and microwave conditions
Investigation of the chemoselective and enantioselective oxidation of α-thio-β-chloroacrylamides
摘要:
An investigation of the chemoselective and enantioselective oxidation of alpha-thio-beta-chloroacrylamides is described. The alpha-thio-beta-chloroacrylamides can be selectively oxidised to either the racemic sulfoxide or the sulfone very efficiently. The asymmetric sulfur oxidation of alpha-thio-beta-chloroacrylamides is also discussed, with sulfoxide enantioselectivities of up to 52% ee achieved using the Kagan oxidation, and up to 71% ee when the Bolm oxidation is employed. While the enantioselectivities achieved are modest, these are among the most highly functionalised sulfides investigated in catalytic asymmetric oxidation, and the resulting enantioenriched sulfoxides have significant synthetic potential. (C) 2008 Elsevier Ltd. All rights reserved.
The influence of reaction conditions on the Diels–Alder cycloadditions of 2-thio-3-chloroacrylamides; investigation of thermal, catalytic and microwave conditions
作者:Marie Kissane、Denis Lynch、Jay Chopra、Simon E. Lawrence、Anita R. Maguire
DOI:10.1039/c0ob00368a
日期:——
The DielsâAlder cycloadditions of cyclopentadiene and 2,3-dimethyl-1,3-butadiene to a range of 2-thio-3-chloroacrylamides under thermal, catalytic and microwave conditions is described. The influence of reaction conditions on the outcome of the cycloadditions, in particular the stereoselectivity and reaction efficiency, is discussed. While the cycloadditions have been attempted at the sulfide, sulfoxide and sulfone levels of oxidation, use of the sulfoxide derivatives is clearly beneficial for stereoselective construction of DielsâAlder cycloadducts.
Investigation of the chemoselective and enantioselective oxidation of α-thio-β-chloroacrylamides
作者:Marie Kissane、Denis Lynch、Jay Chopra、Simon E. Lawrence、Anita R. Maguire
DOI:10.1016/j.tetasy.2008.04.033
日期:2008.5
An investigation of the chemoselective and enantioselective oxidation of alpha-thio-beta-chloroacrylamides is described. The alpha-thio-beta-chloroacrylamides can be selectively oxidised to either the racemic sulfoxide or the sulfone very efficiently. The asymmetric sulfur oxidation of alpha-thio-beta-chloroacrylamides is also discussed, with sulfoxide enantioselectivities of up to 52% ee achieved using the Kagan oxidation, and up to 71% ee when the Bolm oxidation is employed. While the enantioselectivities achieved are modest, these are among the most highly functionalised sulfides investigated in catalytic asymmetric oxidation, and the resulting enantioenriched sulfoxides have significant synthetic potential. (C) 2008 Elsevier Ltd. All rights reserved.