Palladium-Catalyzed Hydroarylation of Propiolamides. A Regio- and Stereocontrolled Method for Preparing 3,3-Diarylacrylamides
摘要:
A general regio- and stereoselective synthesis of 3,3-diarylacrylamides is reported. Palladium-catalyzed coupling reactions of propiolamides with aryl halides provide arylpropiolamides. A subsequent hydroarylation reaction of these arylpropiolamides with aryl halides, catalytic palladium, an amine base, and formic acid in refluxing ethyl acetate provides 3,3-diarylacrylamides regio- and stereoselectively. The unique stereo- and regiocontrol is presumed to proceed through careful reaction parameters that allow intramolecular coordination of the propiolamide amide functionality to the transient palladium-alkyne complex. Palladium-catalyzed hydroarylation of propiolamides has not been studied; however, preliminary results from related systems suggest that regioselective addition can be achieved. The methodology as a synthesis tool is demonstrated in an efficient route to previously difficult-to-prepare potent, benzimidazole antiviral targets. In addition, the synthesis scope is explored where, by judicious choice of reaction sequence and aryl iodide, either the Z- or E-geometric isomer of a given pair of 3,3-diarylacrylamides is independently prepared.
Palladium-Catalyzed Hydroarylation of Propiolamides. A Regio- and Stereocontrolled Method for Preparing 3,3-Diarylacrylamides
摘要:
A general regio- and stereoselective synthesis of 3,3-diarylacrylamides is reported. Palladium-catalyzed coupling reactions of propiolamides with aryl halides provide arylpropiolamides. A subsequent hydroarylation reaction of these arylpropiolamides with aryl halides, catalytic palladium, an amine base, and formic acid in refluxing ethyl acetate provides 3,3-diarylacrylamides regio- and stereoselectively. The unique stereo- and regiocontrol is presumed to proceed through careful reaction parameters that allow intramolecular coordination of the propiolamide amide functionality to the transient palladium-alkyne complex. Palladium-catalyzed hydroarylation of propiolamides has not been studied; however, preliminary results from related systems suggest that regioselective addition can be achieved. The methodology as a synthesis tool is demonstrated in an efficient route to previously difficult-to-prepare potent, benzimidazole antiviral targets. In addition, the synthesis scope is explored where, by judicious choice of reaction sequence and aryl iodide, either the Z- or E-geometric isomer of a given pair of 3,3-diarylacrylamides is independently prepared.
[EN] PYRAZOLOPYRIDAZINE DERIVATIVES FOR THE TREATMENT OF HEPATITIS C<br/>[FR] DÉRIVÉS DE PYRAZOLOPYRIDAZINE POUR LE TRAITEMENT DE L'HÉPATITE C
申请人:BRISTOL MYERS SQUIBB CO
公开号:WO2011106340A1
公开(公告)日:2011-09-01
The disclosure provides compounds of formula (I), including their salts, as well as compositions and methods of using the compounds. The compounds have activity against hepatitis C virus (HCV) and may be useful in treating those infected with HCV.
The disclosure provides compounds of formula I, including their salts, as well as compositions and methods of using the compounds. The compounds have activity against hepatitis C virus (HCV) and may be useful in treating those infected with HCV.
A regio- and stereocontrolled method for preparing 3,3-diarylacrylamides
作者:Lynne A. Hay、David Mitchell
DOI:10.1016/s0040-4039(97)01528-1
日期:1997.9
Palladium-catalyzed hydroarylation of acetylenes provides regio- and stereodefined olefins. This methodology has been extended to arylpropiolamides where 3,3-diarylaclylamides are prepared stereospecifically. In an independent fashion, both the E- and Z-isomers were prepared by judicious choice of arylpropiolamide preparation and the palladium catalyzed hydroarylation reaction. (C) 1997 Elsevier Science Ltd.