Gold(III) Chloride Catalyzed Cyclization of α-Hydroxyallenes to 2,5-Dihydrofurans
作者:Anja Hoffmann-Röder、Norbert Krause
DOI:10.1021/ol016205+
日期:2001.8.9
corresponding 2,5-dihydrofurans 2 by using 5-10 mol % of gold(III) chloride as catalyst. This mild and efficient cyclization method can be applied to alkyl- and alkenyl-substituted allenes at room temperature, furnishing tri- and tetrasubstituted dihydrofurans in good to excellent chemical yields and with complete axis to centerchiralitytransfer.
In this account, recent accomplishments in the field of target-oriented synthesis involving allenes are summarized. Allenic α-amino acid derivatives 9, which are of interest as possible vitamin B 6 decarboxylase inhibitors, were prepared by 1,6-addition of the cyano-Gilman reagent t-Bu 2 CuLi-LiCN to 2-amino-substituted enynoates 8. and selective deprotection at either the amino or the ester group