Preparation of amorolfine

1. A process for the preparation of a compound of formula (I):

said process comprising the steps of:

(i) contacting a compound of formula (II):

with a Friedel-Crafts catalyst selected from the group consisting of gallium chloride, antimony pentafluoride, molybdenum pentachloride, indium chloride, and antimony pentachloride; and

(ii) adding one equivalent of 2-halogeno-2-methylbutane, and wherein the reaction mixture obtained in step (i) is cooled to a temperature from −40° to −60° C. prior to step (ii).

2. The process as defined by claim 1 , wherein the reaction mixture obtained in step (i) is cooled to a temperature of −50° C. prior to step (ii).

3. The process as defined by claim 1 , wherein the Friedel-Crafts catalyst is selected from the group consisting of gallium chloride, antimony pentachloride and antimony pentafluoride.

4. The process as defined by claim 1 , wherein the compound of formula (II) is present in 1 part of 2-halogeno-2-methylbutane per 1 part of the compound of formula (II).

5. The process as defined by claim 1 , further comprising one or more of the following steps:

(a) pouring the reaction mixture from step (ii) onto an ice-water mixture;

(b) separating the organic phase;

(c) washing the organic phase with optionally acidified, water,

(d) washing the organic phase with water;

(e) washing the organic phase from step (d) with a solution of sodium hydroxide;

(f) washing the organic phase from step (e) with water;

(g) exchanging the dichloromethane solvent to toluene;

(h) performing toluene/water extractions;

(i) removing the toluene by distillation; and

(j) distilling the crude Amorolfine base from step (i).

6. The process as defined by claim 1 , wherein said 2-halogeno-2-methylbutane is 2-chloro-2-methylbutane.

7. The process for producing a compound of formula (V):

comprising the process as defined by claim 1 .