Studies of 2,5;6,10;8,10-Tri-μ-hydro-nonahydro-nido-nonaborate(1-), -: Preparation, Crystal and Molecular Stucture, Nuclear Magnetic Resonance Spectra, Electrochemistry, and Reactions

DOI: 10.1039/DT9850001645

Source and publish data:

Journal of the Chemical Society, Dalton Transactions p. 1645 - 1654 (1985)

Update date:2022-08-17

Topics:

Authors:

Jacobsen, Grant B.

Meina, Dominic G.

Morris, John H.

Thomson, Colin

Andrews, Steven J.

et al. et al.

Read Full Text PDF DownLoad Join now for total 90,000,000 free articles

Article abstract of DOI:10.1039/DT9850001645

Studies of 2,5;6,10;8,10-tri-μ-hydro-nonahydro-nido-nonaborate(1-) ^- have involved new syntheses, which have led to crystals suitable for the determination of the X-ray crystal and molecular structure, through reactions of B9H13(SMe2) with ^- or other bases.Crystallographic study of reveals the structure of the anion to be that of a nido-nine-vertex cage, based on the parent bicapped square antiprism with one 5-connected vertex removed.The pentagonal open face is symmetrically bridged by three (μ-H) atoms (two involving the lowest connected boron), conferring effective C_s symmetry upon the polyhedron.Crystals are monoclinic, space group P2₁/n, with a=26.759(10), b=10.340(4), c=27.044(5) Angtroem, β=103.47(2) deg, and Z=8.Using 6 777 diffracted intensities recorded at 185 K on an Enraf-Nonius CAD4 diffractometer, the structure has been refined to R 0.0847, R' 0.1216.The 11B, two-dimensional 11B(COSY), and 1H n.m.r. parameters all confirm the structural assignment and the n.m.r. spectra have been assigned unambiguously.Cyclic and a.c. voltammetry and coulometry of ^- in several solvents at Pt led to the electrochemical parameters and to an isomer-specific electrochemical synthesis of anti-^-.Chemically, the ⁺ salt of ^- reacted with HCl to give ^-, whereas the n4>⁺ salt yielded anti-B18H22; reactions with CF3CO2H gave primarily anti-^-.