反应详情

Other compounds of formula (I) within the scope of the invention may be obtained by conventional methods of organic chemistry. For example, halogen atoms may be introduced by diazotisation of an appropriate amino derivative followed by application of the Sandmeyer reaction. In this way 1-iodo-5-nitro-4-thiocyanatonaphthalene may be prepared from 1-amino-5-nitro-4-thiocyanatonaphthalene. Elimination of the amino group from the latter compound via its diazonium derivative gives 1-nitro-8-thiocyanatonaphthalene, which may also be prepared by diazotisation of 1-amino-8-nitronaphthalene followed by reaction with an alkali metal thiocyanate. Similarly, 1-amino-8-chloronaphthalene gives 1-chloro-8-thiocyanatonaphthalene. Acylamino derivatives may be obtained by acylation of the corresponding amino compounds. Thus, reaction of 1-amino-5-nitro-4-thiocyanatonaphthalene with acetic anhydride in acetic acid gives the 1-acetylamino derivative. 1-Amino-5-nitro-4-thiocyanatonaphthalene may itself be obtained by direct thiocyanation of 1-amino-5-nitronaphthalene; bis-thiocyanation gives 1-amino-2,4-dithiocyanato-5-nitronaphthalene, which may be converted into 2-amino-6-nitro-5-thiocyanatonaphtho[1,2-d]thiazole by refluxing in an alcoholic solvent containing a small quantity of a mineral acid. Likewise, thiocyanation of 1-amino-5-cyanonaphthalene gives 1-amino-5-cyano-4-thiocyanatonaphthalene; diamination of this compound via its diazonium derivative yields 1-cyano-8-thiocyanatonaphthalene.

1. customfollowed by application of the Sandmeyer reaction