Synthesis of 5‐Carbapterocarpens by α‐Arylation of Tetralones Followed by One‐Pot Demethylation/Cyclization with BBr₃

Abstract

Abstract 5‐Carbapterocarpens, one of them displaying estrogenic activity, were prepared from α‐aryltetralones in high yields through a one‐pot, BBr 3 ‐promoted O ‐demethylation and cyclization sequence. The key α‐aryltetralone intermediates were obtained by direct α‐arylation of tetralones with o ‐alkoxybromoarenes in the presence of Pd 2 (dba) 3 (2.5 mol‐%) and t Bu 3 PHBF 4 (10 mol‐%) as catalysts, together with 2.5 equiv. of KOH in dioxane/H 2 O (4:1), under microwave irradiation conditions (80 W, 100 °C, 40 min), leading to α‐monoaryltetralones in good yields.