Acyclic stereoselection. 44. Diastereoselectivity in the ortho ester Claisen rearrangement of chiral propargylic alcohols. Use of .beta.-allenic esters as chiral methylmalonaldehyde synthons
Acyclic stereoselection. 44. Diastereoselectivity in the ortho ester Claisen rearrangement of chiral propargylic alcohols. Use of .beta.-allenic esters as chiral methylmalonaldehyde synthons
Studies on Pd<sup>0</sup>-Catalyzed Cyclization of<i>N</i>-3,4-Alkadienyl Toluenesulfonamides with Organic Halides: Selective Synthesis of 2,3-Dihydropyrroles, 1,2,3,6-Tetrahydropyrridines, and Azetidines
作者:Shengming Ma、Fei Yu、Jing Li、Wenzhong Gao
DOI:10.1002/chem.200600431
日期:2007.1
The palladium-catalyzed coupling-cyclization of beta-amino allenes with organic halides ranging from arylhalide to 1-alkenyl halide was studied. 2,3-Dihydro-1H-pyrroles were obtained by reaction of 3-substituted-5-unsubstituted-3,4-allenyl amides under conditions A, while the reaction of 5-substituted-3,4-allenyl amides afforded 1,2,5,6-tetrahydropyridines and/or azetidines with high de under conditions