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Protecting group-free synthesis of 1,2-azaborines: a simple approach to the construction of BN-benzenoids.

ABSTRACT: The protecting group-free synthesis of a versatile 1,2-azaborine synthon 5 is described. Previously inaccessible 1,2-azaborine derivatives, including the BN isostere of phenyl phenylacetate and BN1 triphenylmethane were prepared from 5 and characterized. The structural investigation of BN phenyl phenylacetate revealed the presence of a unique NH-carbonyl hydrogen bond that is not present in the corresponding carbonaceous analogue. The methyne CH in BN triphenylmethane was found to be less acidic than the corresponding proton in triphenylmethane. The gram-quantity synthesis of the parent 1,2-azaborine 4 was demonstrated, which enabled the characterization of its boiling point, density, refractive index, and its polarity on the ET(30) scale.

SUBMITTER: Abbey ER

PROVIDER: S-EPMC3809131 | biostudies-literature | 2013 Aug

REPOSITORIES: biostudies-literature

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Protecting group-free synthesis of 1,2-azaborines: a simple approach to the construction of BN-benzenoids.

Abbey Eric R ER Lamm Ashley N AN Baggett Andrew W AW Zakharov Lev N LN Liu Shih-Yuan SY

Journal of the American Chemical Society 20130819 34

The protecting group-free synthesis of a versatile 1,2-azaborine synthon 5 is described. Previously inaccessible 1,2-azaborine derivatives, including the BN isostere of phenyl phenylacetate and BN1 triphenylmethane were prepared from 5 and characterized. The structural investigation of BN phenyl phenylacetate revealed the presence of a unique NH-carbonyl hydrogen bond that is not present in the corresponding carbonaceous analogue. The methyne CH in BN triphenylmethane was found to be less acidic ...[more]

PMID: 23914914

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