Electroorganic synthesis, 57. Synthesis of advanced prostaglandin precursors by Kolbe electrolysis, II. – Preparation of coacids and anodic initiated tandem radical‐addition / radical‐coupling reaction with (1′R,4′S,3R/S)‐3‐(cis‐4‐acetoxycyclopent ‐2‐enyloxy)‐3‐ethoxypropionic acid

Abstract

AbstractThe α‐silyl‐substituted carboxylic acids 4 and 10 were prepared and with other coacids subjected to a mixed Kolbe electrolysis with β‐cyclopentenyloxypropanoate 1. The stereochemical course of this cyclization reaction was determined on the basis of the 4‐methyl‐substituted product 23 by 1H‐NMR‐NOE spectroscopy. Conversion of the bicyclic reaction products 21b–d to advanced prostaglandin precursors such as lactone 30 was achieved in few steps. magnified image