Premium
Stereo‐ and Regiospecific 6‐ endo ‐ trig ‐Cyclization of Aryl Radicals, an Entry to Novel Progesterone‐Antagonists of the Androstane Series
Author(s) -
Ottow Eckhard,
Neef Günter,
Wiechert Rudolf
Publication year - 1989
Publication title -
angewandte chemie international edition in english
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.831
H-Index - 550
eISSN - 1521-3773
pISSN - 0570-0833
DOI - 10.1002/anie.198907731
Subject(s) - androstane , radical , chemistry , steric effects , aryl , stereochemistry , radical cyclization , organic chemistry , alkyl
The phenyl radicals 1 undergo 6‐ endo‐trig cyclization instead of the 5‐ exo‐trig cyclization observed for simple alkenylphenyl radicals. The cyclization products 2 are key compounds for the synthesis of 3 (e.g., XOH, YCCCH 3 ), the first competitive progesterone antagonists in the androstane series. The formation of 2 by a neophyl rearrangement can be excluded for steric reasons. RH, OCH 3 , N(CH 3 )2.