A THERMAL POTENTIAL [6 + 41 2H-TRANSFER REACTION IN A CYCLIC DIMER OF DIMETHYL 2a,8a-DIHYDROCYCLO-PENT[c,d]AZULENE-1,2-DICARBOXYLATE

摘要

Azulenes and dimethyl acctylenedicarboxylatc (ADM) react under catalysis of diethylaluminum chloride (Et2AlCl) in toluene to corresponding 2a,8a-dihydrocyclopenta[cd]azulene-1,2-dicarboxylates, which on further influence of Et2AlCl dimerize by bond formation between the central C(8b) and C(8'b) atoms and inter alia C(3) and C(8') atoms. The thus formed heptacyclic compounds undergo on heating in tetralin an intramolecular disproportionation by transfer of two H-atoms from one to the other part of the heptacyclic structures. The kinetics of this process is studied with partially deuterated heptacycles.