preparation method of triphenylmethyl bromide_industrial additives

background and overview^[1]

triphenylmethyl bromide can be used as a pharmaceutical synthesis intermediate.

preparation^[1]

a method for recovering triarylmethyl halides such as triphenylmethyl bromide from sucrose derivatization. the method includes the following steps

(a) triarylmethylation of sucrose in the presence of amines to form 6,r,6′-tri-o-triarylmethylsucrose and triarylmethylated sucrose by-products;

(b) acylate 6,1′,6′-tri-o-triarylmethylsucrose in the presence of amine to form 6,1′,6′-tris-o-triarylmethylsucrose pentaester and triarylmethylated sucrose ester by-products;

(c) the product of step (b) is separated into i) βjl’jβ’-tri-o-triarylmethylsucrose pentaester, and ii) a mixture containing triarylmethylated sucrose esters;

(d) contacting the first by-product component of the mixture comprising step (c) ii) with an aqueous hydrogen halide solution under conditions sufficient to remove the amine therefrom, thereby forming a triaryl methylated compound containing one or more washing by-product components of sucrose impurities;

(e) contacting the washed by-product component with a hydrogen halide to cleave the triarylmethyl from the one or more triarylmethylated sucrose impurities to form a first crude triaryl a methyl halide component, including a triarylmethyl halide and one or more used triarylmethyl compounds selected from the group consisting of triarylmethanol, triarylmethyl esters and triarylmethyl ethers;

(f) contacting the first crude triarylmethyl halide with a hydrogen halide to convert the one or more spent triarylmethyl compounds into a triarylmethyl halide to form purified triarylmethyl halide component; and

(g) recovery of triarylmethane halide such as triphenylmethyl bromide from the output of step (f).

main reference materials

[1] wo2008070043 – trityl chloride recovery