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Methylborane
1,2-Dimethyldiborane is an organoboron compound with the formula [(CH3)BH2]2. Structurally, it is related to diborane, but with methyl groups replacing terminal hydrides on each boron. It is the dimer of methylborane, CH3BH2, the simplest alkylborane. 1,2-Dimethyldiborane can exist in a cis- and a trans arrangement. 1,2-Dimethyldiborane is an easily condensed, colorless gas that ignites spontaneously in air. An isomer of 1,2-dimethyldiborane is 1,1-Dimethyldiborane, 1,1-dimethyldiborane, known as unsymmetrical dimethyldiborane, which has two methyl groups on one boron atom. Other methylated versions of diborane including methyldiborane, trimethyldiborane, tetramethyldiborane. Trimethylborane exists as a monomer. Preparation Methylboranes were first prepared by Hermann Irving Schlesinger, H. I. Schlesinger and A. O. Walker in the 1930s. In a more modern synthesis, 1,2-dimethyldiborane is produced by treating lithium methylborohydride with hydrogen chloride: :2 LiCH3BH3 + 2 HCl â ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetramethyldiborane
Dimethylborane, (CH3)2BH is the simplest dialkylborane, consisting of a methyl group substituted for a hydrogen in borane. As for other boranes it normally exists in the form of a dimer called tetramethyldiborane or tetramethylbisborane or TMDB ((CH3)2BH)2. Other combinations of methylation occur on diborane, including monomethyldiborane, trimethyldiborane, 1,2-dimethylborane, 1,1-dimethylborane and trimethylborane. At room temperature the substance is at equilibrium between these forms. The methylboranes were first prepared by Hermann Irving Schlesinger, H. I. Schlesinger and A. O. Walker in the 1930s. Properties Tetramethyldiborane has two boron atoms linked by a two hydrogen atom bridge, and each boron is linked to two methyl groups. A tetramethyldiborane molecule belongs to the D2h point group. Its infrared spectrum shows a strong absorption band at 1602 cm−1 due to bridging hydrogen, a weak band at 1968 cm−1 and lines due to methyl between 900 and 1400 cmâ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |