Lewis acid mediated reactions of 1-cyclopropyl-2-arylethanones with allenic esters: a facile synthetic protocol for the preparation of dihydrofuro[2,3-h]chromen-2-one derivatives.
TMSOTf-mediated reactions of 1-cyclopropyl-2-arylethanones with allenic esters afford a novel method for the synthesis of dihydrofuro[2,3-h]chromen-2-one derivatives in moderate to good yields. This process is a sequential reaction involving a nucleophilic ring-opening reaction of the cyclopropane by H(2)O, two intermolecular aldol-type reactions and one intramolecular aldol-type reaction, a cyclic transesterification, dehydration, and aromatization mediated by Lewis acid.
Shi
Min
M
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Lu, Shanghai 200032, China. mshi@mail.sioc.ac.cn
Tang
Xiang-Ying
XY
Yang
Yong-Hua
YH