Short communication: Thermal stability of the diazohydroborate [1‐N 2 B 10 H 9 ] − : degradation to [B 20 H 18 ] 2− anion

The thermal stability of the monodiazohydroborate NMe 4 [1‐N 2 B 10 H 9 ] was studied by thermogravimetric analysis. Under two different atmospheres (air and argon), the thermal decomposition starts at a temperature between 140 and 160 °C. The decomposition residue obtained was separated on a silica gel column. 11 B NMR, IR and electrospray mass spectroscopy analyses of the different fractions separated showed that the above decomposition produces (NMe 4 ) 2 [B 20 H 18 ] as major product (90%), along with smaller amounts of residual NMe 4 [1‐N 2 B 10 H 9 ] (5%), (NMe 4 ) 2 [B 12 H 12 ] and boric acid. Copyright © 2003 John Wiley & Sons, Ltd.