Synthesis and Properties of the Weakly Coordinating Anion [Me3NB12Cl11]-

The weakly coordinating anion [Me3NB12Cl11](-) has been prepared by a simple two-step procedure. The anion [Me3NB12Cl11](-) is easily obtained in batches of up to 20g by chlorination of the known [H3NB12H11](-) anion with SbCl5 at about 190 degrees C and subsequent N-methylation with methyl iodide. Starting from Na[Me3NB12Cl11], several synthetically useful salts with reactive cations ([NO](+), [Ph3C](+), and [(Et3Si)(2)H](+)) were prepared. Full spectroscopic (NMR, IR, Raman, TGA, MS) characterization and single-crystal X-ray diffraction studies confirmed the identity and purity of the products. The thermal, chemical, and electrochemical stability as well as the basicity of the [Me3NB12Cl11](-) anion is similar to that of the structurally related weakly coordinating 1-carba-closo-dodecaborate and closo-dodecaborate anions. The facile preparation of the [Me3NB12Cl11](-) anion and its ideal chemical and physical properties make it a cheap alternative to other classes of weakly coordinating anions.