The nucleophilicity of M(SPh)₃ (M = P, As) and L-As(SPh)₂ (L = Ph, 2-O₂N-Ph) towards fatty acyl chlorides, RCOCl

Article type: Research Article

Authors: Ioannou, P.V. | Tsivgoulis, G.M.

Affiliations: Department of Chemistry, University of Patras, Patras, Greece

Note: [] Corresponding author. Fax: +30 610 997118; E-mail: [email protected]

Abstract: The reaction of P(SPh)3, As(SPh)3, Ph-As(SPh)2 and 2-O2N-C6H4-As(SPh)2 with palmitoyl chloride was studied. In dichloromethane at room temperature these reactions did not give the thiol ester RCOSPh, but diphenyl disulfide PhSSPh instead, with yields that were depended on the absence or the presence of an activator [pyridine or 4-dimethylaminopyridine (DMAP)]. At 90°C P(SPh)3 and palmitoyl chloride gave RCOSPh but not PhSSPh either in the absence or in the presence of pyridine or DMAP. On the other hand, As(SPh)3, Ph-As(SPh)2 and 2-O2N-C6H4-As(SPh)2 with palmitoyl chloride at 90°C gave mixtures of RCOSPh and PhSSPh in proportions depending on the absence or the presence of pyridine or DMAP. Probable mechanistic paths to these products are proposed.

Keywords: Triphenyl trithiophosphite, triphenyl trithioarsenite, diphenyl phenyldithioarsonite, diphenyl 2-nitrophenyldithioarsonite, acyl chlorides, nucleophilicity, alpha effect

DOI: 10.3233/MGC-2011-0047

Journal: Main Group Chemistry, vol. 10, no. 2, pp. 177-185, 2011