Palladium-catalyzed synthesis of substituted 1,5-benzodiazocines and 1,5-benzooxazocines from bis-nucleophiles and an allylic dicarbonate.

Abstract

A palladium-catalyzed synthesis of substituted 1,5-benzodiazocines and 1,5-benzooxazocines from bis-nucleophiles and an allylic dicarbonate was developed. N,N'-Disubstituted 2-aminobenzylamines underwent cyclization in the presence of Pd(PPh₃)₄ to afford the corresponding 1,5-benzodiazocines in 40% to quantitative yields. The reaction was also applicable to N,N'-disubstituted naphthalene-1,8-diamines, providing naphthalene-fused diazocine derivatives. N-Substituted 2-hydroxybenzylamines reacted under Pd(OAc)₂/DPPP catalysis to give the corresponding 1,5-benzooxazocines in 54% to quantitative yields. These cyclizations construct two carbon-heteroatom bonds through sequential allylic substitutions and provide straightforward access to diverse eight-membered N,N- and N,O-heterocycles bearing an exocyclic methylene group.