nido-Undecaboranes and -borates of the type B11H13L and B11H12L-

The Lewis base SMe2 in 7-B11H13(SMe2) (1a) can be replaced by the amines L = NH2(CH(2)tBu), NH2Cy, NH2Ph, NH2(4-C6H4Me), py, chinoline or the phosphanes L = PPh3, PMePh2, yielding 7-B11H13L (1b-i). The borane 1a can be deprotonated by certain amines, alkanides, or hydrides to give the anion 7-B11H12(SMe2)(-) (2a). Replacing the base SMe2 in the anion 2a by weak bases gives B11H12L- (L = PPb3, MeCN; 2h, j). Upon reaction of 1a with the amine NH2(CH(2)tBu)(-) in the ratio 1:2, a deprotonation and the substitution of SMe2 by the amine are observed, 7-B11H12[NH2(CH(2)tBu)](-) (2b) being formed. At 170 degreesC, the 7-isomers 1b, f are isomerized into a mixture of the corresponding land 2-isomers (1b', f' and 1b", f", respectively).