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 Diastereoselective Friedel−Crafts Reaction of Furans with 8-Phenylmenthyl Glyoxylate
摘要:
The Friedel-Crafts reaction of (1R)-8-phenylmenthyl glyoxylate with variously substituted furans was found to be efficiently promoted by SnCl(4) or magnesium salts with high diastereoselectivities. MgBr(2) performs especially well under simple, undemanding conditions, giving both high yields and high diastereoselectivities (> 90%). The reaction afforded chiral substituted furan-2-yl-hydroxyacetic acid esters, compounds of potentially high synthetic interest.
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%.
Highly Diastereoselective Friedel−Crafts Reaction of Furans with 8-Phenylmenthyl Glyoxylate
The Friedel-Crafts reaction of (1R)-8-phenylmenthyl glyoxylate with variously substituted furans was found to be efficiently promoted by SnCl(4) or magnesium salts with high diastereoselectivities. MgBr(2) performs especially well under simple, undemanding conditions, giving both high yields and high diastereoselectivities (> 90%). The reaction afforded chiral substituted furan-2-yl-hydroxyacetic acid esters, compounds of potentially high synthetic interest.