Substances Related to the Boranes

Bromodihorane, B H Br, has a structure essentially identical with that of diborane except that a bromine atom replaces one of the non-bridging hydrogen atoms. The B Br bond length, 1.934 0.010 A, corresponds to bond number 0.80 (the B—Br single-bond length is 

Tebraboron tetrachloride, B4C14, differs from the boranes in that the ligancy of boron is only 4. The boron atoms lie at the comers of a regular tetrahedron.103 Each boron atom forms three B—B bonds, with the other atoms of the tetrahedron, and a B—Cl bond, directed out from the center of the molecule. The B—Cl bond length, 1.70 A, 

104 Quantum mechanical calculations have been reported to show instability of these substances Eberhardt, Crawford, and Lipscomb, Inc. cii. (74) H. C, Longuet-Higgins and M. de V. Eoberte, Proc. Roy. Soc. Lotidon A2J0, 110 (1956). 

622 (1950). This electron-diffractiop Study is supported by a spectroscopic investigation W. C. Price, J. Chem. Phye. 17, 1044 (1949). 

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