Process for the preparation of dibenzenesulfonimide

Abstract

The present invention provides a process for the preparation of dibenzenesulfonimide.

Claims

1. A process for preparing a dibenzenesulfonimide of Formula I, ##STR00007## comprising the steps of: a) treating a compound of Formula III with a compound of Formula IV in the presence of a compound of Formula V in acetonitrile at a temperature of below 30 C., ##STR00008## wherein R.sub.1 and R.sub.2 are independently selected from the group consisting of hydrogen, fluorine, chlorine, bromine, iodine, C.sub.1-6 alkyl, C.sub.1-6 alkoxy, C.sub.1-6 alkylsulfonyl, C.sub.1-6 perfluoroalkylsulfonyl and cyano; and R.sub.3, R.sub.4 and R.sub.5 are independently selected from the group consisting of optionally substituted C.sub.1-6 alkyl and optionally substituted C.sub.1-6 aryl, and b) isolating the compound of Formula I.

2. The process of claim 1, wherein step b) is carried out by layer separation, distillation, filtration, evaporation, decantation, or a combination thereof.

Description

EXAMPLE

Example 1

(1) Preparation of Dibenzenesulfonimide

(2) Benzenesulfonamide (50 g), acetonitrile (150 g) and triethylamine (97 g) were taken in a reaction vessel and stirred for 45 minutes. The benzene sulfonyl chloride (69 g) was added drop-wise to the reaction mixture at 20 C. The reaction mixture was additionally stirred at 25 C. for 45 minutes. The acetonitrile was recovered by evaporation and solid reaction mass was dissolved in sodium hydroxide (20%, 300 g). The aqueous layer was separated, washed with chloroform and acidified with hydrochloric acid (35%) to obtain the title product.

(3) Yield (g): 90

(4) Purity (% by HPLC): 99.2