Pd-catalyzed cyclodimerization of alkenyl and aryl dibromides: Construction of dibenzo[a,e]cyclooctatetraenes

Cyclooctatetraenes, including dibenzocyclooctatetraenes, are structurally interesting compounds and are widely used in many areas. Therefore, the development of synthetic methods for such compounds has long been attractive. In this work, a Pd-catalyzed coupling reaction between alkenylbromides and arylbromides has been realized. Multi-substituted 1,4-dibromo-1,3-butadienes and o-bromo-2-(2-bromovinyl)benzenes underwent a Pd-catalyzed cyclodimerization reaction to afford the corresponding multi-substituted cyclooctatetraenes and dibenzo[a,e]cyclooctatetraenes, respectively, in high yields and with excellent regioselectivity.

Graphical AbstractDibenzo[a,e]cyclooctatetraene derivatives are efficiently and regioselectively generated from a palladium-catalyzed [4+4] cyclic homo-coupling of o-bromo-2-(2-bromovinyl)benzenes.Figure optionsDownload full-size imageDownload as PowerPoint slide