Process for the preparation of (+) - 2 - (3,4-dichlorophenyl) - 4 - hidroxibutilamina dextru00f3gira, for the preparation of acid (-) - 3 - cyano - (3 - (3,4 - dichloro phenyl) propiu00c8nico acid, 3 - cyano - (3 - (3),4 - diclorofenil propiu00c8nico, and compound)