Synthesis, structure and reactions of a series of 1,2-dicyanoethylenedithiolate coordinated dimeric Mo(V) complexes

View the MathML source[Bu4N]2[Mo2VO4(mnt)2] (where mnt = 1,2-dicyanoethylenedithiolate) (1), reacts with HX (X = SPh, Cl, Br) to form a series of complexes, View the MathML source[Bu4N]2[Mo2VO3(mnt)2(L)2](L=SPh(2a),Cl(2b),Br(2c)). In acidic–alcoholic medium 1 with thiophenol yields another series of compounds, View the MathML source[Bu4N][Mo2VO2(mnt)2(μ-SPh)2(μ-OY)](Y=Me(3a),Et(3b),iPr(3c)). Under similar conditions tertiary-butanol does not coordinate where a complex can only be isolated in the presence of bromide as View the MathML source[Bu4N]2[Mo2VO2(mnt)2(μ-O)(μ-SPh)(μ-Br)](4). The use of excess of methanesulfonic acid in the presence of HSPh or HSEt facilitates methanesulfonate coordination in complexes, View the MathML source[Bu4N]2[Mo2VO2(mnt)2(μ-O)(μ-SZ)(μ-CH3SO3)](Z=Ph(5),Et(6)). All these complexes are structurally characterized by single crystal X-ray study. These complexes show pH dependent hydrolytic reaction leading to quantitative reversal to the starting complex, 1. Complexes 2a–c respond to hydrolysis in CH2Cl2 with the intermediate formation of EPR active molybdenum(V) species.