Synthesis and Electronic Spectra of Some Disperse Dyes Derived from N—2—Cyanoethyl—1,2,3,4—tetrahydroquinoline

Various monoazo dyes suitable for transfer printing have been prepared from N—2cyanoethyl—1, 2, 3, 4—tetrahydroquinoline and compared with the corresponding N—methyl (kairoline) derivatives. The presence of a β—cyanoethyl group brings about significant hypsochromic shifts of the first absorption band and leads to some improvement in light—fastness properties on polyester fibre.