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Borane dimethylsulfide (BMS) is a complexed borane reagent that is widely used for hydroborations. [4] Much of the original work on hydroboration employed diborane as a source of BH 3. Usually however, borane dimethylsulfide complex BH 3 S(CH 3) 2 (BMS) is used instead. [5] It can be obtained in highly concentrated forms. [6]
Hydroboration–oxidation is an anti-Markovnikov reaction, with the hydroxyl group attaching to the less-substituted carbon. The reaction thus provides a more stereospecific and complementary regiochemical alternative to other hydration reactions such as acid-catalyzed addition and the oxymercuration–reduction process.
One example is thexylborane (ThxBH 2), produced by the hydroboration of tetramethylethylene: [6] A chiral example is monoisopinocampheylborane. Although often written as IpcBH 2, it is a dimer [IpcBH 2] 2. It is obtained by hydroboration of (−)‐α‐pinene with borane dimethyl sulfide. [7] Dialkylboranes are also rare for small alkyl groups.
Borane dimethylsulfide (BMS) is a chemical compound with the chemical formula BH 3 ·S(CH 3) 2. It is an adduct between borane molecule ( BH 3 ) and dimethyl sulfide molecule ( S(CH 3 ) 2 ). It is a complexed borane reagent that is used for hydroborations and reductions .
Borane makes a strong adduct with triethylamine; using this adduct requires harsher conditions in hydroboration. This can be advantageous for cases such as hydroborating trienes to avoid polymerization. More sterically hindered tertiary and silyl amines can deliver borane to alkenes at room temperature. Borane(5) is the dihydrogen complex of
Borane–tetrahydrofuran is an adduct derived from borane and tetrahydrofuran (THF). These solutions, which are colorless, are used for reductions and hydroboration, reactions that are useful in synthesis of organic compounds. A common alternative to BHF•THF is borane–dimethylsulfide, which has a longer shelf life and effects similar ...
Catalyzed hydroboration-oxidation of substituted alkenes can be rendered enantioselective. In 1990, Brown and co-workers achieved asymmetric hydroboration using an achiral catalyst and chiral borane sources derived from ephedrine and pseudoephedrine. In most cases, the regioselectivity was poor although the ee values can be close to 90%. [16]
A borane is a compound with the formula BR x H y although examples include multi-boron derivatives. A large family of boron hydride clusters is also known. In addition to some applications in organic chemistry , the boranes have attracted much attention as they exhibit structures and bonding that differs strongly from the patterns seen in ...