The synthesis, structure and reactivity of copper(I) complexes of poly(thioether)borates

A series of poly((alkylthio)methyl)borates; RTt- (1), PhTt- (2), Et2Bt - (8) (RTt- = tetrakis((methylthio)methyl)borate, PhTt- = phenyltris((methylthio)methyl)borate, Et 2Bt- = diethylbis((methylthio)methyl)borate); and phenyltris((arylthio)methyl)borates; PhTtPh- (3), PhTtp -Tol- (4) (PhTtPh- = phenyltris((phenylthio)methyl)borate, PhTtp-Tol- = phenyltris(( p- tolylthio)methyl)bomrae) have been synthesized and characterized. Complexes with divalent, first row transition metals, [RTt]2Co and [PhTt]2M (M = Fe, Co, Ni), have been prepared and characterized. Comparisons are made to metal complexes of 1,4,7-trithiacyclononane (ttcn), 1,4,7- triazacyclononane, and hydridotris(pyrazol-1-yl)borate, Tp- . All complexes have been characterized by X-ray diffraction and are isostructural. [Cu(CH3CN)4][BF4] has been reacted with PhTt-, PhTtPh-, PhTt p-Tol-, PhTtt -Bu- (5), Ph2Bt- (6), and Ph2BtPh- (7) to form a series of structurally diverse Cu(I) complexes with 1:1 stoichiometry (PhTtt-Bu- = phenyltris(( t-butylthio)methyl)borate, Ph2Bt- = diphenylbis((methylthio)methyl)borate, Ph2BtPh- = diphenylbis((phenylthio)methyl)borate). X-ray analysis shows that [(PhTt)Cu]4 and [(Ph2Bt)Cu]4 are tetrameric, while [(PhTtPh)Cu.CH3CN] forms an extended, one-dimensional structure in the solid state. 7 reacts with [Cu(CH3CN)4][BF4] in acetonitrile to form monomeric [(Ph2BtPh)Cu(CH3CN) 2], that has been characterized by X-ray diffraction, and in acetone to form oligomeric [(Ph2BtPh)Cu]x. The oligomer can be converted readily to the monomer by dissolution in acetonitrile. [(PhTtt-Bu)Cu]n is oligomeric in non-coordinating solvents, as indicated by 1H NMR spectroscopy, while [(PhTtP-Tol)Cu]x is only soluble in donor solvents, yielding a monomer. The reactivity of the Cu(I) complexes has been explored and stable monomeric complexes of the type [LCu(X)] (X = PPh3, Py, L = 2--5; X = NO, L = 2 ; X = CH3CN, L = 3, 5) and [LCu(X) 2] (X = PPh3, L = 6--8; X Py, CH3 CN, L = 6, 7) have been prepared and characterized. [(L)Cu(PPh3)] (L = 2--4) and [(Et2Bt)Cu(PPh 3)2] have been characterized by X-ray diffraction. [(PhTt)Cu] 4 has also been reacted with [Et4N]SPh, [PPN]NO2 to form [Et4N][(PhTt)Cu(SPh)] and [PPN][(PhTt)Cu(NO2)], respectively.