One-Step Synthesis of 5a,11a-Janusene Imide Employing 2,3-Dibromo-N-methylmaleimide as Acetylene Equivalent

Abstract

Synthesis of janusene (5,5a,6,11,11a,12-hexahydro-5,12:6,11-di-o-benzenonaphthacene) requires several reaction steps starting from anthracene. In this account, one-pot, three steps synthesis of janusene N-methyl-5a,11a-dicarboximide employing 2,3-dibromo-N-methylmaleimide as acetylene equivalent is described. This thermal reaction is simple synthetic procedure in comparison to sequential-multi step [4+2] cycloaddition routes. Here 2,3-dibromo-Nmethylmaleimide acts effectively as 'molecular glue' bridging two anthracene molecules together.