ISOCYANATES CONTAINING AZIDE GROUPS

1,126,177. Azide-containing isocyanates and a process for their preparation. FARBENFABRIKEN BAYER A.G. 27 April, 1966 [14 May, 1965; 9 March, 1966], No. 18523/66. Heading C2C. Organic mono- and poly-isocyanates containing azide groups are obtained by reacting primary mono- or poly-amines containing azide groups with phosgene in an amount of 1À5 to 3 moles of phosgene per mole of amine group at a temperature of -20‹ to +200‹ C. The invention also comprises certain novel compounds [see below) which may be prepared by the above process. The reaction is preferably effected in an organic solvent and the starting materials may be obtained by protecting, e.g. by acylation, some of the amino groups of the amine and converting the remaining amino group(s) into an azide group, e.g. with sodium nitrite and an acid, and deacylating the protected amino group(s) in an alkaline medium. In the examples the following compounds, which are claimed to be novel, are prepared by the above process: 3- and 4-isocyanatoazidobenzene, 4-isocyanato-2-azido-toluene, 2- isocyanato-4-azido toluene, m-azido benzoic acid-2-isocyanato isopropyl ester, m- and pazido-sulphonylphenylisocyanate, 1-methyl-2- isocyanatobenzene-5-sulphonic acid azide and 1 -chloro - 2-isocyanatobenzene-5-sulphonic acid azide.