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Trimethylboron
Trimethylborane (TMB) is a toxic, Pyrophoricity, pyrophoric gas with the formula B(CH3)3 (which can also be written as Me3B, with Me representing methyl). Properties As a liquid it is colourless. The strongest line in the infrared spectrum is at 1330 cm−1 followed by lines at 3010 cm−1 and 1185 cm−1. Its melting point is −161.5 °C, and its boiling point is −20.2 °C. Vapour pressure is given by , where ''T'' is temperature in kelvins. Molecular weight is 55.914. The heat of vapourisation is 25.6 kJ/mol. Preparation Trimethylborane was first described in 1862 by Edward Frankland, who also mentioned its adduct with ammonia. Due to its dangerous nature the compound was no longer studied until 1921, when Alfred Stock and Friedrich Zeidler took advantage of the reaction between boron trichloride gas and dimethylzinc. Although the substance can be prepared using Grignard reagents the output is contaminated by unwanted products from the solvent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Society Of Chemistry
The Royal Society of Chemistry (RSC) is a learned society (professional association) in the United Kingdom with the goal of "advancing the chemical sciences". It was formed in 1980 from the amalgamation of the Chemical Society, the Royal Institute of Chemistry, the Faraday Society, and the Society for Analytical Chemistry with a new Royal Charter and the dual role of learned society and professional body. At its inception, the Society had a combined membership of 34,000 in the UK and a further 8,000 abroad. The headquarters of the Society are at Burlington House, Piccadilly, London. It also has offices in Thomas Graham House in Cambridge (named after Thomas Graham, the first president of the Chemical Society) where ''RSC Publishing'' is based. The Society has offices in the United States, on the campuses of The University of Pennsylvania and Drexel University, at the University City Science Center in Philadelphia, Pennsylvania, in both Beijing and Shanghai, China and in Ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dibutyl Ether
Dibutyl ether is a chemical compound belonging to the ether family with the molecular formula of . It is colorless, volatile, and flammable liquid and has peculiar ethereal smell. Liquid dibutyl ether is lighter than water. On the other hand, the vapor is heavier than air. It is not soluble in water, but it is soluble in acetone and many other organic solvents. Due to this property, dibutyl ether is used as solvent in various chemical reactions and processes. For example, phenyllithium is commercially available as a ca. 1.8M solution in dibutyl ether. Because of the formation of peroxides, it should be protected from heat, light and air. Synthesis Dibutyl ether is obtained from dehydration of 1-butanol with sulfuric acid as a catalyst and dehydrating agent: :2 → + Industrially, dibutyl ether can be obtained by dehydration of 1-butanol on alumina at 300 °C. Reactions This compound is generally stable to oxidation, reduction, and base. Strong acids like HI and HBr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trimethylarsine
Trimethylarsine (abbreviated TMA or TMAs) is the chemical compound with the formula (CH3)3As, commonly abbreviated As Me3 or TMAs. This organic derivative of arsine has been used as a source of arsenic in microelectronics industry, a building block to other organoarsenic compounds, and serves as a ligand in coordination chemistry. It has distinct "garlic"-like smell. Trimethylarsine had been discovered as early as 1854. Structure and preparation AsMe3 is a pyramidal molecule. The As-C distances average 1.519 Å, and the C-As-C angles are 91.83° Trimethylarsine can be prepared by treatment of arsenic oxide with trimethylaluminium: :As2O3 + 1.5 lMe3sub>2 → 2 AsMe3 + 3/n (MeAl-O)n Occurrence and reactions Trimethylarsine is the volatile byproduct of microbial action on inorganic forms of arsenic which are naturally occurring in rocks and soils at the parts-per-million level. Trimethylarsine has been reported only at trace levels (parts per billion) in landfill gas from Germany, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trimethylphosphine
Trimethylphosphine is a neutral organophosphorus compound with the formula P(CH3)3, commonly abbreviated as PMe3. This colorless liquid has a strongly unpleasant odor, characteristic of alkylphosphines. The compound is a common ligand in coordination chemistry. Structure and bonding It is a pyramidal molecule with approximate ''C''3''v'' symmetry. The C–P–C bond angles are approximately 98.6°. The C–P–C bond angles are consistent with the notion that phosphorus predominantly uses the 3p orbitals for forming bonds and that there is little sp hybridization of the phosphorus atom. The latter is a common feature of the chemistry of phosphorus. As a result, the lone pair of trimethylphosphine has predominantly s-character as is the case for phosphine, PH3. PMe3 can be prepared by the treatment of triphenyl phosphite with methylmagnesium chloride: : 3 CH3MgCl + P(OC6H5)3 → P(CH3)3 + 3 C6H5OMgCl The synthesis is conducted in dibutyl ether, from which the more volatile PM ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimethyldiborane
1,2-Dimethyldiborane is an organoboron compound with the formula CH3)BH2sub>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, 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 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 → (CH3BH2)2 + 2 H2 + 2 LiCl Instead of hydr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
