Acid form of Trofimenko’s scorpionates, H(Tp

Abstract

We report a re-examination of Trofimenko’s original protocol for the preparation of the acid form of his hydrotris(pyrazolyl)borates, H(TpR,R′), by the treatment of M(TpR,R′) with glacial acetic acid. It is concluded that the protocol is effective as long as the 3-substituent of the pyrazolyl moiety is sufficiently bulky to provide steric protection to the acidic N–H proton. The solid-state structure of H(TptBu,Me), the acid form of the popular TptBu,Me ligand is also presented.