Acyl C→N migration in the thioureidomethylation of 2-(4-methylbenzoyl)cyclohexanone

The thioureidomethylation of the sodium enolate of 2-(4-methylbenzoyl)cyclohexanone 3 with N-(tosylmethyl)thiourea 1a or N -(azidomethyl)thiourea 2 in acetonitrile results in the unexpected formation of N -(4-methylbenzoyl)- N’ -[(2-oxocyclohexyl)-methyl]thiourea 6, which was structurally characterised by X-ray diffraction analysis.