PHOTOCHROMIC COMPOUNDS

摘要

PCT No. PCT/GB94/00628 Sec. 371 Date Nov. 2, 1995 Sec. 102(e) Date Nov. 2, 1995 PCT Filed Mar. 25, 1994 PCT Pub. No. WO94/22850 PCT Pub. Date Oct. 13, 1994A naphthopyran compound of general formula (I) (I) wherein R1 represents a group of the formula -NR2R3 wherein each of R2 and R3, which may be the same or different, independently represents an alkyl group, or a carbocyclic or heterocyclic group, or R2 and R3 taken together with the nitrogen atom to which they are attached represent a heterocyclic ring having one or more hetero atoms and which may optionally carry at least one substituent selected from alkyl, aryl, or heteroaryl groups; each of R4 and R5, which may be the same or different, independently represents an alkyl, alkenyl, carbocyclic or heterocyclic group, or R4 and R5 taken together with the carbon atom to which they are attached form a carboxylcyclic ring or a heterocyclic ring; and R6 represents a hydrogen atom or a substituent selected from alkyl, alkoxy, aryl, aryloxy, heteroaryl, halogen, a group of formula R1 as defined above, azo, imino, amide, carboxylate, ester, cyano, trifluoromethyl or nitro, and in addition R6 may represent a carbocyclic or heterocyclic ring fused to ring A. The naphthopyran compounds of the invention are useful as photochromic materials in lenses, e.g. sunglasses, and photochromic transparencies for cars and aircraft. The invention also provides, as new intermediate compounds, amine-substituted chloro-naphthols and amine-substituted naphthols.