Syntheses of (−)-Funebrine and (−)-Funebral, Using Sequential Transesterification and Intramolecular Cycloaddition of a Chiral Nitrone
作者:Osamu Tamura、Nobutaka Iyama、Hiroyuki Ishibashi
DOI:10.1021/jo030257q
日期:2004.3.1
The first syntheses of (−)-funebrine [(−)-1] and (−)-funebral [(−)-2] are described. The syntheses feature sequential formation of nitrone VI frommethyl glyoxylate (5) with oxime 6, transesterification of nitrone VI with (E)-crotyl alcohol (4), and intramolecular cycloaddition of the resulting nitrone VII bearing crotyl ester to afford cycloadduct 7 as a major product. The adduct 7 was readily elaborated