Unlocking the metallaboratrane cage: reversible B-H activation in platinaboratranes.

The reaction of the new platinaboratrane salt [PtH(PTol3){B(mt)3}]Cl(Pt-->B)8 (mt = methimazolyl, Tol = C6H4Me-4) with 2 equivalents of PR3 (R = Me, Et) affords, via hydride migration to boron and ligand substitution, the salts [Pt(PR3)2{kappa 2-S,S'-HB(mt)3}]Cl, which slowly undergo B-H reactivation, to afford, ultimately, the platinaboratrane salts [PtH(PR3){B(mt)3}]Cl(Pt-->B)8.