Highly Enantioselective Synthesis of 2-Furanyl-hydroxyacetates from Furans via the Friedel−Crafts Reaction
摘要:
The Friedel-Crafts reaction of alkyl glyoxylates with variously substituted furans was found to be efficiently catalyzed under simple, undemanding conditions by a 6,6'-dibromo-BINOL/Ti(IV) complex with high enantioselectivity. The reaction afforded chiral substituted 2-furanyl-hydroxyacetic acid esters, compounds of high synthetic interest, in good yield and enantiomeric excess, in most examples in the range of 90-97%.
Highly Enantioselective Synthesis of 2-Furanyl-hydroxyacetates from Furans via the Friedel−Crafts Reaction
摘要:
The Friedel-Crafts reaction of alkyl glyoxylates with variously substituted furans was found to be efficiently catalyzed under simple, undemanding conditions by a 6,6'-dibromo-BINOL/Ti(IV) complex with high enantioselectivity. The reaction afforded chiral substituted 2-furanyl-hydroxyacetic acid esters, compounds of high synthetic interest, in good yield and enantiomeric excess, in most examples in the range of 90-97%.
The high-pressure (10 kbar) reaction of 2-methylfuran I with alkyl glyoxylates 2, catalyzed by the chiral (Salen)Co(II) complex 4, afforded the Friedel-Crafts products 3 both in good yield (up to 70%) and enantio selectivity (up to 76% ee). (C) 2003 Elsevier Ltd. All rights reserved.
Highly Enantioselective Synthesis of 2-Furanyl-hydroxyacetates from Furans via the Friedel−Crafts Reaction
作者:Jakub Majer、Piotr Kwiatkowski、Janusz Jurczak
DOI:10.1021/ol800927w
日期:2008.7.17
The Friedel-Crafts reaction of alkyl glyoxylates with variously substituted furans was found to be efficiently catalyzed under simple, undemanding conditions by a 6,6'-dibromo-BINOL/Ti(IV) complex with high enantioselectivity. The reaction afforded chiral substituted 2-furanyl-hydroxyacetic acid esters, compounds of high synthetic interest, in good yield and enantiomeric excess, in most examples in the range of 90-97%.