Methyldiborane, CH3B2H5, or monomethyldiborane is the simplest alkyldiborane, consisting of a methyl group substituted for a hydrogen in diborane. As with other boranes it exists in the form of a dimer with a twin hydrogen bridge that uses three-center two-electron bonding between the two boron atoms, and can be imagined as methyl borane (CH3BH2) bound to borane (BH3). Other combinations of methylation occur on diborane, including 1,1-dimethylborane, 1,2-dimethyldiborane, trimethyldiborane, tetramethyldiborane, and trimethylborane (which is not a dimer). At room temperature the substance is at equilibrium between these molecules.

CAS：23777-55-1
中文别名：
英文别名：methyl diborane;[methyl(tritio)boranyl]boron;deuterated methyldiborane;Methyldiborane(6);$l^{2}-boranyl(methyl)boron;$l^{1}-boranyl(methyl)boron;Methyldiboran;
分子式：CH3B2
分子量：36.6565
精确质量：37.0421
Psa：0.0
Logp：-0.1778

危险品运输编码：UN 1953
危险类别：2.3