2,4-Bismethylthio-1,3,2,4-dithiadiphosphetane 2,4-disulfide, IIa, is prepared from O,O-dimethyldithiophosphoric acid, Ia, and P4S10 at 160 deg C. 2,4-Bis(4-phenoxyphenyl)-1,3,2,4-dithiadiphosphetane 2,4-disulfide, IIc, and 2,4-bis(4-phenyl-thiolphenyl)-1,3,2,4-dithiadiphosphetane 2,4-disulfide, IId, are prepared at 160 deg C from P4S10 and diphenylether and diphenylsulfides, respectively.Carboxylic acids RCOOH (R=CH3, C2H5, n-C3H7, n-C4H9, C6H5CH2, C6H5) react with compound Ia at 130 deg C to give the corresponding methyl dithioesters.Carboxylic acids RCOOH (R=C6H5-CH2, C6H5) react with compound Ib at 200 deg C for 15 min to give the corresponding ethyl dithioesters, while low boiling acids (R=CH3, C2H5, n-C3H7) yielded mixtures of the corresponding ethyl dithioester and ethyl carboxylate.Carboxylic acid chlorides RCOCl (R=ClCH2, C2H5, t-C4H9, C6H5CH2, C6H5, p-NO2C6H4) react with compound IIa at 80 deg C to give the corresponding methyl dithioesters in good yields.S-Substituted thioesters react with IIc at 85 deg C to give the corresponding dithioesters in good yields.Dihydro-2(3H)-furanone, VI, and 5-methyl-2(3H)-furanone, VII, react with IIa at 80 deg C to give dihydro-2(3H)-thiophenethione, VIII and 2,2'-dithiobis(5-methyl thiophene), IX, respectively.Also XI reacts with IIa, IIc, and IId to give VIII in nearly quantitative yields.
