AbstractIn connection with earlier work on the synthesis of 9β, 10α‐steroids, a new and practical synthesis of rac‐17α‐hydroxy‐des‐A‐androst‐9‐en‐5‐one (19) has been developed, based on a novel stereoselective condensation of 7‐hydroxy‐1‐nonen‐3‐one (3) with 2‐methyl‐cyclopentane‐1, 3‐dione (9) and subsequent transformations of the resulting tricyclic diene ether 12.
作者:M. Rosenberger、D. Andrews、F. DiMaria、A. J. Duggan、G. Saucy
DOI:10.1002/hlca.19720550129
日期:1972.1.31
A novel and general synthesis of δ-lactones fromglutaraldehyde is described. The dialdehyde is first reacted with an alkyl or substituted alkyl Grignard reagent to afford a δ-hydroxyaldehyde in good yield. These aldehydes exist preferentially in the cyclic hemiacetal form (δ-lactols). Oxidation of the latter compounds to give δ-lactones is readily achieved with silver oxide or bromine. The δ-lactols