A New Construction of 2-Alkoxypyrans by an Acylation−Reductive Cyclization Sequence
摘要:
A new convergent synthetic approach to a pyran motif common to many naturally occurring structures is described. In this approach, two fragments are joined by esterification, and a subsequent intramolecular reductive cyclization affords the 2-hydroxypyran.
Pyran Annulation: Asymmetric Synthesis of 2,6-Disubstituted-4-methylene Tetrahydropyrans
作者:Gary E. Keck、Jonathan A. Covel、Tobias Schiff、Tao Yu
DOI:10.1021/ol025645d
日期:2002.4.1
[reaction: see text] A reaction process for the asymmetric construction of a variety of cis or trans disubstituted pyrans is described. This sequences allows for the asymmetric convergent union of two aldehydes with silyl-stannane reagent 1 in a two-step process: catalytic asymmetric allylation of the first aldehyde using 1 with a BITIP catalyst, followed by reaction of the alcohol so obtained with
A New Construction of 2-Alkoxypyrans by an Acylation−Reductive Cyclization Sequence
作者:Lars V. Heumann、Gary E. Keck
DOI:10.1021/ol070573h
日期:2007.5.1
A new convergent synthetic approach to a pyran motif common to many naturally occurring structures is described. In this approach, two fragments are joined by esterification, and a subsequent intramolecular reductive cyclization affords the 2-hydroxypyran.