A concise, stereoselective synthesis of functionalized tetrahydrofuranols has been developed that involves heating readily available chloropolyols in water. These reactions are operationally straightforward and chemoselective for the formation of tetrahydrofurans, obviating the need for complicated protecting group strategies. The efficiency of this process is demonstrated in a short asymmetric synthesis of the natural product (+)-goniothalesdiol.
A Concise and Stereoselective Synthesis of Hydroxypyrrolidines: Rapid Synthesis of (+)-Preussin
作者:Jason A. Draper、Robert Britton
DOI:10.1021/ol101631e
日期:2010.9.17
A convergent and stereoselective synthesis of 2,5-disubstituted 3-hydroxypyrrolidines has been developed that involves reductive annulation of beta-Iminochlorohydrins, which are readily available from beta-ketochlorohydrins, and provides rapid access to a variety of 2,5-syn-pyrrolidines. Application of this process to the concise (three-step) synthesis of the fungal metabolite (+)-preussin and analogues of this substance is reported.
Chlorine, an atom economical auxiliary for asymmetric aldol reactions
作者:Shira D. Halperin、Robert Britton
DOI:10.1039/c3ob27462d
日期:——
An auxiliary strategy has been developed for asymmetricreactions of aldehydes in which the auxiliary itself is not chiral, but a single chlorine atom introduced via organocatalytic α-chlorination. The stereodirecting influence of the chlorine atom is then exploited prior to its removal by radical reduction. This strategy is demonstrated in the synthesis of several aldols (92–99% ee) and the natural