Dichloroborane diethyl etherate

Synthesis of alkyldichloroboranes. Dichloroborane diethyl etherate reacts with olehns very slowly in diethyl ether or TH F. However, addition of boron trichloride (Lewis acid) results in a rapid reaction at 0° to give alkyldichloroboranes in 80-90% yield ... 

HYDROBORATION, REAGENTS His-(3,6-dimethyl)borepane. Bix(3,5-dimeth-yl)borinane. Bis((rans-2-methylcydo-hesyOborane. Catceholborane. Diborane. Dichloroborane diethyl etherate. Dicyclo-hexylborane. Diisopinocamphenoborane. 2,3-Dimethyl-2-butylborane. Monochloro-borane-Ethyl etheiate. 

If alkyldichloroboranes are specifically required, dichloroborane-dimethyl sulfide is the reagent of choice. It is more stable and more convenient than the dichloroborane-diethyl ether complex, but its hydroborating properties are very similar." Dichloroborane complexes ethers even more strongly than monochloroborane, and its reactions with alkenes in this solvent are slow and lead to mixtures. Therefore, it is generally used in pentane and trichloroborane is added to liberate uncomplexed dichloroborane. Under these conditions it readily gives alkyldichloroboranes on reaction with alkenes or alkenyldichloro-boranes on reaction with alkynes. " " The latter reaction has been applied to alkynylsilanes (equation 44)." ... 

Dichlorobicyclo[3.2.1]oct-2-ene, 233 Dichlorobis(benzonitrile)palladium, 129 Dichloroborane, 129-130 Dichloroborane diethyl etherate, 130... 

Dialkylchloroboranes (R2BCI), monoalkylchloroboranes (RBHCl), and dial-kenylchloroboranes can be prepared by controlled hydroboration of alkenes or alkynes with BH2CI, and this reagent can also be used for synthesis of 5-chloro-boracycloalkanes by hydroboration-thermal depolymerization of dienes e.g. Scheme 16). Dichloroborane diethyl etherate is useful for synthesis of alkyl-and alkenyldichloroboranes. ... 

Related Reagents. Acetyl Chloride Bromotrimethylsi-lane A-Chlorosuccinimide-Dimethyl Sulfide Dichloroborane Diethyl Etherate Hydrogen Chloride Iodine lodotrimethyl-... 

The products are Hquids, soluble in various solvents and stable over prolonged periods. Monochloroborane is an equiUbtium mixture containing small amounts of borane and dichloroborane complexes with dimethyl sulfide (81). Monobromoborane—dimethyl sulfide complex shows high purity (82,83). Solutions of monochloroborane in tetrahydrofuran and diethyl ether can also be prepared. Strong complexation renders hydroboration with monochloroborane in tetrahydrofuran sluggish and inconvenient. Monochloroborane solutions in less complexing diethyl ether, an equiUbtium with small amounts of borane and dichloroborane, show excellent reactivity (88,89). Monochloroborane—diethyl etherate [36594-41-9] (10) may be represented as H2BCI O... 

Although dichloroborane reacts direcdy with alkenes in the gas phase (118), its complexes with diethyl ether and dimethyl sulfide are so strong that direct hydroboration does not proceed (119,120). The addition of a decomplexing agent, eg, boron trichloride, is necessary for hydroboration. 

Apparently chlorine and trifluoromethanesulfonate groups attached to boron and silicon can be replaced by fluorine in lithium fluoride at lower temperatures than that reported for C-X (X = halogen) exchange. Dichloroborane 5 is converted to the difluoro derivative 6 with lithium fluoride in diethyl ether at 0-22°C.7... 

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