Patent ID: 7112682

Claim:
A process for the preparation of a compound of the formula II: which consists essentially the steps of: (a) preparing a solution of hydroxylamine-O-sulfonic acid in a suitable organic solvent; (b) preparing a solution of a suitable base in a suitable organic solvent; (c) preparing a solution of a compound of the formula I in a suitable organic solvent; (d) contacting simultaneously and proportionally said solution from said step (a) and said solution from said step (b) with said solution from step (c) taken in a suitable reaction vessel at a suitable reaction temperature to provide said compound of formula (II) in high purity and high yields; wherein R is hydrogen, C 1 –C 4 -alkyl, C 1 –C 4 -alkoxy, benzyloxy or fluoroalkyl or fluoroalkoxy of the formula C n H x F y or OC n H x F y wherein n is an integer from 1 to 4, x is an integer from 0 to 8, y is an integer from 1 to 9 and sum of x and y is 2n+1; R 1 and R 2 are the same or different and are each independently selected from hydrogen, C 1 –C 4 -alkyl, C 1 –C 4 -alkoxy, benzyloxy or fluoroalkyl or fluoroalkoxy of the formula C n H x F y or OC n H x F y wherein n is an integer from 1 to 4, x is an integer from 0 to 8, y is an integer from 1 to 9 and sum of x and y is 2n+1; or R 1 and R 2 taken together with the carbon atoms to which they are attached form a C 5 –C 8 cyclic ring; and m is 1 or 2.