| Abstract: | C-S bond activation of thiophenols and mercaptans is of great importance but has rarely been reported. In this paper we report the C-S bond cleavage of the thiolato ligand of [2,6-(tBu2PO)2C6H3]NiSCH2Ph (1) mediated by BH3·THF. The treatment of 1 with an excess amount of BH3·THF in THF at room temperature afforded the borohydride complex [2,6-(tBu2PO)2C6H3]Ni(η2-BH4) (2) as the only product. The reaction of 1 with 2 equiv. of BH3·THF in THF at room temperature for 48 h produced the hydride complex [2,6-(tBu2PO)2C6H3]NiH (3) and the mercapto complex [2,6-(tBu2PO)2C6H3]NiSH (5). As a new complex, 5 was also independently synthesized by a salt metathesis reaction of the corresponding chloride complex with NaSH and fully characterized by multinuclear NMR, FTIR, HRMS, X-ray crystallography and elemental analysis. A possible mechanism for the formation of 5 was proposed. It was supposed that 5 formed through BH3 mediated C-S bond cleavage of the thiolato ligand of 1. The result would initiate further studies on the transition metal catalyzed borane mediated C-S bond activation of mercaptans. |
