title: Rearrangements of N-acyl isothioureas. Alternate access to acylguanidines from cyanamides.
abstract: We report a tin-free one-pot radical approach to the synthesis of N-acyl isothioureas and acylguanidines from N-acyl cyanamides. Photoactivated reduction of aromatic disulfides in the presence of Hünig's base results in hydrothiolation of the cyanamide moiety, followed by spontaneous 1,3-migration of the acyl group. Onward reaction of the isothioureas obtained with amines led to the corresponding N-acylguanidines, where the acyl group is attached to the nitrogen atom formerly at the cyano-end of the starting material.
authors.affiliation: UPMC Université Paris 06, IPCM (UMR 7201), 4 Pl. Jussieu, C. 229, 75005 Paris, France.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Maestri
authors.forename: Marie-Hélène
authors.initials: MH
authors.lastname: Larraufie
authors.forename: Cyril
authors.initials: C
authors.lastname: Ollivier
authors.forename: Max
authors.initials: M
authors.lastname: Malacria
authors.forename: Louis
authors.initials: L
authors.lastname: Fensterbank
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Lacôte