The reaction of trithiomolybdate [PPh4](2)[MoOs3] (1) with 2 equiv of trimethylchlorosilane generated trithio-chloro molybdate [PPh4][MoClS3] (2) in high yield, by way of a siloxy complex [PPh4)[Mo(OSiMe3)S-3] (3). This intriguing reaction provided us with a convenient entry into a series of mononuclear molybdenum trisulfido complexes, [PPh4][MoS3X] (4, X = Cp*; 6a, X = (SBu)-Bu-t; 6b, X = SPh; 6c, X = SMes (Mes = mesityl); 6d, X = STip (Tip = 2,4,6-triisopropylphenyl); 6e, X = SDmp (Dmp = 2,6-dimesitylphenyl); 7, X = NPh2; 8a, X = (OBu)-Bu-t; 8b, X = OPh; 8c, X = OC(CH2)Bu-t; 8d, X = OC(CH2)Ph), which were obtained by the reactions of 2 with the corresponding potassium salts. In a similar manner, a citrate complex [PPh4][MoS3(Me(3)cit)] (9, Me(3)cit = OC(CH2CO2Me)(2)(CO2Me)) was synthesized, which may model the molybdenum site of the nitrogenase FeMo-cofactor, The molecular structures of 2, 6c, 7, 8a, 8b, 8c, and 9 were determined by X-ray crystallography.