Rutheniun-catalyzed cycloisomerization of o-(ethynyl)phenylalkenes to diene derivatives via skeletal rearrangement |
| |
Authors: | Madhushaw Reniguntala J Lo Ching-Yu Hwang Chun-Wei Su Ming-Der Shen Hung-Chin Pal Sitaram Shaikh Isak R Liu Rai-Shung |
| |
Institution: | Department of Chemistry, National Tsing-Hua University, Hsinchu 30043, Taiwan, Republic of China. |
| |
Abstract: | Treatment of a series of 2',2'-disubstituted (o-ethynyl)styrenes with TpRu(PPh(3))(CH(3)CN)(2)PF(6) (10 mol %) in benzene (80 degrees C, 12-18 h) efficiently gave 2-alkenyl-1H-indene derivatives. This catalytic reaction represents an atypical enyne cycloisomerization with skeletal rearrangement of starting enyne, where the C=C bond is completely cleaved and inserted by the terminal alkynyl carbon. The reaction mechanism was elucidated by a series of deuterium and (13)C labeling experiments, as well as by changing the substituents at the phenyl moieties. The mechanism is proposed to involve the following key steps: 5-endo-dig cyclization of ruthenium-vinylidene intermediate, a nonclassical ion formation, and the "methylenecyclopropane-trimethylenemethane" rearrangement. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|