Crystal structure of bis­(diiso­propyl­amino)­fluoro­borane

Abstract

Bis(diiso­propyl­amino)­fluoro­borane was previously identified as a product of reactions of (diiso­propyl­amino)­difluoro­boranes in the presence of Na/K alloy, but its structure was never elucidated. The structure reported here will contribute to the understanding of the basic binding situation and properties, and will provide a more com­plete picture when com­pared with analogous structures.

The predominantly planar structure of a fluoro-substituted bis­(di­alkyl­amino)­borane, C₁₂H₂₈BFN₂, was obtained from the reaction of boron trifluoride diethyl etherate with lithium diiso­propyl­amide and its structure is presented here. While the B—F bond length is in the typical range of single B—F bonds, the B—N bond length indicates a partial double-bond character. The sterically demanding isopropyl groups on both amides increase the N—B—N angle and enable inter­molecular van der Waals inter­actions.