Zinc Salt Promoted Diastereoselective Synthesis of Chiral Propargylamines Using Chiral Piperazines and Their Enantioselective Conversion into Chiral Allenes
作者:Mariappan Periasamy、Polimera Obula Reddy、Athukuri Edukondalu、Manasi Dalai、Laxman M. Alakonda、Bantu Udaykumar
DOI:10.1002/ejoc.201402766
日期:2014.9
Zinc chloride catalyzed reactions of chiralpiperazine derivatives 4a–d with 1-alkynes and aldehydes give chiralpropargylamines in 67–95 % yields with up to 99:1 dr. The chiralpropargylamines are converted into chiralallenes by usingzinc bromide in short reaction times (1–2 h) in high enantioselectivities (up to 99 % ee) in good yields (up to 89 %). The chiralpiperazines are recovered in good