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Hydroboration with pyridine borane at room temperature.

ABSTRACT: Treatment of pyridine borane (Py.BH3) with iodine, bromine, or strong acids affords activated Py.BH2X complexes that are capable of hydroborating alkenes at room temperature. Evidence is presented for an unusual hydroboration mechanism involving leaving group displacement. In contrast to THF.BH3, hydroboration with Py.BH2I selectively affords the monoadducts. The crude hydroboration products are converted into synthetically useful potassium alkyltrifluoroborate salts upon treatment with methanolic KHF2.

SUBMITTER: Clay JM

PROVIDER: S-EPMC1460016 | biostudies-literature | 2005 Apr

REPOSITORIES: biostudies-literature

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Hydroboration with pyridine borane at room temperature.

Clay Julia M JM Vedejs Edwin E

Journal of the American Chemical Society 20050401 16

Treatment of pyridine borane (Py.BH3) with iodine, bromine, or strong acids affords activated Py.BH2X complexes that are capable of hydroborating alkenes at room temperature. Evidence is presented for an unusual hydroboration mechanism involving leaving group displacement. In contrast to THF.BH3, hydroboration with Py.BH2I selectively affords the monoadducts. The crude hydroboration products are converted into synthetically useful potassium alkyltrifluoroborate salts upon treatment with methanol ...[more]

PMID: 15839656

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