Composition photochromique

1,197,341. Spiro-Beryopyran-indolines. EASTMAN KODAK CO. 6 July, 1967 [6 July, 1966 (2)], No. 31101/67. Heading C2C. [Also in Divisions C3 and C4] The invention comprises photochronic spirobenzopyran-indoline compounds of the formula wherein X represents on or more groups selected from -SO 2 R, SO 2 NR 2 , -COOR, -CONH 2 , -CONR 2 , -CN, -CO.R, where R is an alkyl, aryl or alkanyl group, R1 represents a hydrocarbon group free from ethylenic unsaturation and Y represents one or more substituents in positions 5-8 being H; 6-NO2; 7-(C 2 H 5 ) 2 N; 7-OH; 7-NO 2 ; 8-CH 3 O; 8-NO 2 , 6,8-diBr; 6,8-diCl; 6,8-diNO 2 ; 6-Br-8-NO 2 ; 6-CH 3 O-8-NO 2 ; 8-OH; 8-CH 3 O-6-NO 2 ; 6-CH 3 O; 6-Cl; 6-Br, 6-Br-8-CH 3 O; 8-Br-6-CH 3 O; 8- CH 3 O-5-NO 2 ; 5-NO 2 -8-Cl; 5,6-diCl-6-NO 2 ; 8- CH 3 O-5,7-diNO 2 ;8-CH 3 O-5,6-diNO 2 ; 8-F-6-NO 2 ; 8-Br-6-NO 2 ; 6,8diCl-5-NO 2 ; 8-(C 2 H 5 ) 2 N; or 5,6-benz. The compounds are prepared by condensing a 2-methyleneindole of the formula with a 2-hydroxy-benzaldehyde of the formula in the presence of a solvent and, optionally, a catalyst, e.g., pyridine. The spiro-benzopyran-indolines are used in photodidionic compositions (see Division C4, C3). Methyl 1,3,3 - trimethyl - 2 - methylene - 5-indoline-carboxylate is obtained by heating p-hydrazino-benzoic acid with 2-butanone to obtain p-secbutylidene-hydrazino)-benzoic acid which on heating with dil. H 2 SO 4 yields 2,3- dimethyl-5-indole-carboxylic acid which is esterified with methanol to methyl 2,3-dimethyl-5- indole-carboxylate which is quaternized with methyl iodide to 1,2,3,3-tetramethyl-5-methozycarbonylindoleninium iodide which on heating with NaOH gives the required methylene compound.