Novel Synthesis of 4,5-Diarylphenanthrenes via C<sup>2</sup>−C<sup>6</sup> Cyclization of Benzannulated Enyne−Allenes
作者:Hongbin Li、Jeffrey L. Petersen、Kung K. Wang
DOI:10.1021/jo010687l
日期:2001.11.1
up to 10 h then furnished the 4,5-diarylphenanthrenes 8. Apparently, the transformation from 7 to 8 involves initial prototropic isomerizations to form the benzannulated enyne-allenes 9. Two subsequent formal intramolecular Diels-Alderreactions via the biradicals 10 and 12 derived from the C(2)-C(6) cyclizations then led to 13, which in turn underwent tautomerizations to give 8. The structure of 8a