Fast colorimetric titration protocol for quantification of boron tribromide

Abstract

N,N-Dimethylaniline (DMA) was identified as a colorimetric titrant for accurate quantification of boron tribromide (BBr3) solutions. The initial 1:1 DMA/BBr3 Lewis acid–base adduct formed upon addition of the first equivalent of BBr3 is bright blue in color. Addition of catalytic quantities of BBr3 beyond the first equivalent initiates an instantaneous change in the solution from blue to yellow. This methodology will allow for accurate quantification of BBr3 so that proper stoichiometric amounts of BBr3 may be used to facilitate a broad range of organic transformations. [Display omitted]