COMMUNICATIONS TO THE EDITOR
Jan. 5, 1964
ligand transition in the 7rV orbitals6 A similar band appears a t 29,500 cm. in the spectrum of bis(methy1thio)maleonitrile ; finally, the very intense band a t 37,000 cm. is assigned as the strongly allowed ligand (u") to metal (u*)charge transfer. The electronic spectra of the Pd(MNT)Z2-, Pt(MNT)z2-, and Au(MNT)2- complexes are similar to the spectrum of Ni(MNT)Z2-, and the observed transition energies are consistent with the above assignments.
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6 r V transitions, which are expected to appear somewhat ( 6 ) The T h higher than 31,700 cm. -1, are "perpendicular" and thus much less intense than the strongly allowed bands. These transitions arc probably buried u* band at 37,000 cm. -1. under the u (7) Participant in the Brookhaven Summer Student Program; Columbia University. (8) On leave from the Department of Chemistry, Univcrsity College, London, PI. C. 1.
DEPARTMENT OF CHEMISTRY RICHARD EISENBERG' BROOKHAVEN NATIONAL LABORATORY JAMES A . IBERS UPTON,L. I., NEWYORK OF CHEMISTRY ROBINJ . H . CLARK^ DEPARTMENT COLUMBIA UNIVERSITY HARRYB. GRAY NEWYORK27, NEWYORK RECEIVED OCTOBER 7, 1963
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7 Figure 1.
Diazonium and Carbonyl Derivatives of Polyhedral Boranes Sir: We have now established the scope of BloHlo-2and B12H12-2 derivative chemistry' to be comparable to that of aromatic hydrocarbon chemistry. The key to this advance has been the preparation of several important intermediates, namely, the inner diazonium salt B&s(N2)2 and the dicarbonyls BloH8(CO)zand BIzHIO(C~)Z The diazonium derivative is prepared from BloHlo-2 by reaction with a large excess (10-12 mole equiv.) of aqueous nitrous acid followed by reduction of a precipitated intermediate with NaBH4 in methanoL2
the corresponding BloH8(ligand)pspecies. A similar displacement occurs with amides but the stereochemistry of these products is uncertain. Minor amounts (
