92165-07-6Relevant academic research and scientific papers
Synthesis and X-ray characterisation of a new polycondensed heterocycle obtained by a novel Mn(III)-mediated cascade reaction of 2-cyanophenyl isothiocyanate
Calestani, Gianluca,Capella, Laura,Leardini, Rino,Minozzi, Matteo,Nanni, Daniele,Papa, Romina,Zanardi, Giuseppe
, p. 7221 - 7233 (2001)
2-Cyanophenyl isothiocyanate reacted with Mn(III) acetate in acetic acid or acetonitrile to give fair yields of a new polycondensed heterocycle arising from the joining together of two molecules of the starting isothiocyanate with loss of a CS moiety. The yields were close to 90% when the reaction was carried out in the presence of diethyl malonate. This compound was unambiguously identified by X-ray crystallography. Under the same conditions, 2-(methoxycarbonyl)phenyl isothiocyanate gave a quinazolinimine derivative instead which is likely to arise from cyclisation of an intermediate N,N′-diarylthiourea. The mechanism of formation of the former compound probably involves formation of a N,N′-bis(2-cyanophenyl)thiourea, followed by rearrangement and radical tandem ring closure of the corresponding cyclic imine derivative. This hypothesis is also supported by semiempirical calculations.
