(2-aminophenyl) methanesulfonate

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A diazonium salt solution, prepared by simultaneously introducing a solution of 39.5 g (0.57 mol) of sodium nitrite in 60 ml of water and 105 g (0.57 mol) of 2-aminophenyl methanesulfonate into 200 ml of concentrated hydrochloric acid at 0°-5° C. and stirring for 1 hour at 0° C., was added dropwise at 0°-10° C. to a solution, saturated with sulfur dioxide, of 1.7 g of CuCl2 and 4.5 g of benzyltriethylammonium chloride in 200 ml of 1,2-dichloroethane and 10 ml of water. The means of cooling were removed and stirring was carried out for 30 minutes at 25° C. and then, while slowly increasing the temperature of the reaction mixture, for a further hour at 50° C. The organic phase was separated off, washed with ice water and dried over Na2SO4. After removal of the solvent, an oily residue remained and could be crystallized by trituration with a little methanol. This gave 139 g (90% of theory) of the title compound of melting point 94°-95° C. of cooling were removed stirring was carried out for 30 minutes at 25° C. while slowly increasing the temperature of the reaction mixture for a further hour at 50° C The organic phase was separated off washed with ice water dried over Na2SO4 After removal of the solvent could be crystallized by trituration with a little methanol