Regioselective synthesis of [1-B10H9(SH)]2– and [2-B10H9(SH)]2–: potential agents for boron–Neutron capture therapy of brain tumours
Abstract
The substitution reaction of [1-B10H9(N2)]– with N,N-dimethylthioformamide and the acid-catalyzed nucleophilic substitution of [B10H10]2– with tetramethylthiourea gave [1-B10H9(SCHNMe2)]– and [2-B10H9{SC(NMe2)2}]– respectively. The basic hydrolysis of these thioamide complexes yielded the 1- and 2-isomers of [B10H9(SH)]2– respectively. Their stereochemistry was determined by 1H n.m.r. spectroscopy from the S–Me chemical shift values of their S-methyl derivatives.