Synthesis of the monomeric HBTrip sub 2 (Trip = 2,4,6-i-Pr sub 3 C sub 6 H sub 2 ) and the X-ray crystal structures of (HBMes sub 2 ) sub 2 (Mes = 2,4,6-Me sub 3 C sub 6 H sub 2 ) and HBTrip sub 2

• Published in: Organometallics Vol. 9:1
• Main Authors: Bartlett, R.A., Rasika Dias, H.V., Olmstead, M.M., Power, P.P., Weese, K.J.
• Format: Journal Article
• Language: English
• Published: United States 01.01.1990
• Subjects: ALKYNES; BORON COMPOUNDS; CRYSTAL STRUCTURE; DATA; DATA ANALYSIS; EXPERIMENTAL DATA; HYDROCARBONS; INFORMATION; INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; MEASURING INSTRUMENTS; MEASURING METHODS; NMR SPECTRA; NUMERICAL DATA; ORGANIC BORON COMPOUNDS; ORGANIC COMPOUNDS; SPECTRA 400200 > Inorganic, Organic, & Physical Chemistry; SYNTHESIS
• ISSN: 0276-7333; 1520-6041
• DOI: 10.1021/om00115a023

The synthesis and spectroscopic properties of HBTrip{sub 2} (1) and the X-ray crystal structures of 1 and the dimeric species (HBMes{sub 2}){sub 2} (2) are described. The synthesis of 1 was carried out by treatment of Me{sub 2}S{center dot}BHCl{sub 2} with 2 equiv of TripMgBr in THF solution. Standard workup gave 1 as a colorless crystalline material that exhibited a broad singlet at 73.5 ppm downfield in the {sup 11}B NMR spectrum. X-ray data confirmed a monomeric structure with a planar boron center and a wide CBC angle of 128.0 (4){degree}. The less sterically encumbered 2 was prepared according to a literature procedure. The X-ray crystal structure reveals a dimeric structure with the expected bridging hydrogens. The compounds of 1 and 2 are the first diorganoboranes to be structurally characterized by X-ray crystallography. In addition, the structure of 1 represents the first structural characterization of a monomeric diorganoborane. Crystal data at 225 K for 1 or 140 K for 2, with Mo K{alpha} ({lambda} = 0.71069 {angstrom}) radiation: 1, monoclinic, a = 11.116 (4) {angstrom}, b = 14.869 (5) {angstrom}, c = 17.321 (6) {angstrom}, {beta} = 100.19 (3){degree}, Z = 4, space group P2{sub 1}/c, R = 0.093; 2, monoclinic, a = 12.254 (6) {angstrom}, b = 7.768 (2) {angstrom}, c = 16.785 (6) {angstrom}, {beta} = 109l.43 (3){degree}, Z = 2, space group P2{sub 1}/n, R = 0.047.