Carboranes diborane derivative

Thus, far, all of the known carboranes have been derived either directly or indirectly from reactions of alkynes with various boron hydrides. In these reactions only the carbons participating in the triple bond of the alkyne become skeletal atoms in the carborane. No routes to the hypothetical four-carbon carboranes have been suggested. However, the dehydrogenation of the cyclic diborane derivatives prepared from butadiene 98, 100) should lead to C4BHS and C4B2H6. Unfortunately, such a conversion may require electric discharge conditions, in which case extremely low yields can be expected. 

G in the presence of a catalytic amount of a Lewis base such as dimethylether, (GH2)20. In addition to the gas-phase pyrolysis of diborane, can be prepared by a solution-phase process developed at Union Garbide Gorp. Decaborane is a key intermediate in the preparation of many carboranes and metaHa derivatives. As of this writing, this important compound is not manufactured on a large scale in the western world and is in short supply. Prices for decaborane in 1991 were up to 10,000/kg. 

---