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A 1,3,2-oxazaborolidine dimer derived from (S)-alpha,alpha-diphenylprolinol.

ABSTRACT: The reaction of (S)-alpha,alpha-diphenylprolinol with an excess of borane-tetrahydrofuran complex yields a stable crystalline material with the composition C34H38B2N2O2, which features a borane adduct of a spirocyclic structure with two oxazaborolidine rings joined by a central tetrahedral B atom. This dimeric oxazaborolidine complex, viz. 3,3,3',3'-tetraphenyl-1,1'-spirobi(3a,4,5,6-tetrahydro-3H-pyrrolo[1,2-c][1,3,2]oxazaborole)-7-borane, is the dominant product under various reaction conditions; its crystal structure is consistent with 11B, 1H and 13C NMR and IR analyses.

SUBMITTER: Ortiz-Marciales M

PROVIDER: S-EPMC2814345 | biostudies-literature | 2004 Mar

REPOSITORIES: biostudies-literature

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A 1,3,2-oxazaborolidine dimer derived from (S)-alpha,alpha-diphenylprolinol.

Ortiz-Marciales Margarita M De Jesús Melvin M González Eduvigis E Raptis Raphael G RG Baran Peter P

Acta crystallographica. Section C, Crystal structure communications 20040210 Pt 3

The reaction of (S)-alpha,alpha-diphenylprolinol with an excess of borane-tetrahydrofuran complex yields a stable crystalline material with the composition C34H38B2N2O2, which features a borane adduct of a spirocyclic structure with two oxazaborolidine rings joined by a central tetrahedral B atom. This dimeric oxazaborolidine complex, viz. 3,3,3',3'-tetraphenyl-1,1'-spirobi(3a,4,5,6-tetrahydro-3H-pyrrolo[1,2-c][1,3,2]oxazaborole)-7-borane, is the dominant product under various reaction condition ...[more]

PMID: 15004373

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