Some derivatives of 5,6,11,12-tetrahydrodibenzo[b,f][1,4]diazocine

Abstract

The synthesis of 5,6,11,12-tetrahydro-12-p-tolylsulphonyldibenzo[b,f][1,4]diazocin-6-one and a number of 5-alkyl derivatives is described. Removal of the p-tolylsulphonyl group from these compounds with sulphuric acid was accompanied by a ring contraction, the products being phthalimidines. The 5-methyl derivative (IIb) also gave a phthalimidine when treated with phenyl-lithium. The reduction of the dibenzodiazocines was investigated. An authentic sample of 5,6,11,12-tetrahydro-5-methyldibenzo[b,f][1,4]diazocine was prepared, and a compound to which this structure was previously assigned was shown to be the bis-(12-methyldiazocin-5-yl)methane (XVII). In an attempted synthesis of 11-substituted 5,6-dihydrodibenzo[b,f][1,4]diazocines the only products obtained were substituted benzimidazoles.