Patent GB-553993-A (GB)
Title: Improvements in or relating to dyestuffs and dyestuff intermediates
IPC: C09B23/01
Filed: 1941-12-10
Abstract: 553,993. Cyclopentenyl- and cyclohexenylthiazolines ; dyes; sensitized photographic emulsions. KENDALL, J. D., SUGGATE, H. G., and WOOD, H. W. Dec. 10, 1941, No. 15897. [Class 2 (iii)] [Also in Group XX] Compounds of the general formula wherein R 1 , R 2 , R 3  and R 4  are hydrogen atoms or hydrocarbon groups (e.g. alkyl, aryl, or aralkyl groups) or form part of a saturated carbocyclic ring are prepared by condensing an alkyl, aralkyl, or alicyclic mono-alcohol containing a substituent amino group in the #- position to the alcohol group with #<SP>1</SP>-cyclopentenecarboxylic acid or #<SP>1</SP>-cyclohexenecarboxylic acid or an anhydride or acid halide of such acid, and treating the product with phosphorus pentasulphide. Alcohols specified are #-aminoethyl alcohol, #-amino-n-propyl alcohol, #-amino-iso-propyl alcohol, #-aminophenylethyl alcohol, or 1:2-aminocyclohexanol. 2-(#<SP>1</SP>)- cyclopentenyl-thiazoline is prepared by heating together #-aminoethyl alcohol and #<SP>1</SP>-cyclopentenecarboxylic acid, distilling off #-N-(#<SP>1</SP>- cyclopentenyl)-aminoethyl alcohol at 20 mm. pressure, and reacting with phosphorus pentasulphide. 2-(#<SP>1</SP>)-cyclohexenyl-thiazoline is prepared by heating together #<SP>1</SP>-cyclohexenecarboxylic acid and #-aminoethyl alcohol and distilling off #-N-(#<SP>1</SP>-cyclohexenyl)-aminoethyl alcohol at 25 mm. pressure, and reacting with phosphorus pentasulphide. Dyes are prepared by condensing the alkyl or aralkyl quaternary salt of a compound of the general formula with an alkyl or aralkyl quaternary salt of a 5- or 6-membered heterocyclic nitrogen compound containing in the α position to a heterocyclic nitrogen atom, a thioether group (including an aryl-, alkyl-, or aralkyl-thioether group) or an aminovinyl group of formula -CH=CH-NH (including N-acyl, N-aryl, and N-acylaryl substituted groups of this type). The heterocyclic nitrogen compound may contain one of the usual heterocyclic nuclei, including the diazines described in Specification 425,609. Either or both of the reacting compounds may be used as free bases and converted to quaternary salts during the reaction. The condensation may be effected in the presence of an acid-binding agent, e.g. pyridine, piperidine, triethylamine, sodium acetate, or sodium carbonate. 3:21 - dimethyl - 6:7<SP>1</SP> - trimethylene - thiazolino - thiacarbocyanine iodide is prepared by fusing together 2 - (#<SP>1</SP>) - cyclohexenylthiazoline - methylthiolbenzthiazole, and methyl p-toluenesulphonate, dissolving the product in pyridine, and pouring into potassium iodide solution. 3:2<SP>1</SP> - dimethyl - 4<SP>1</SP>:5<SP>1</SP> - dimethoxy - 6:7<SP>1</SP> - trimethylenethiazolino - thiacarbocyanine iodide, 3:2<SP>1</SP> - dimethyl - 5:6<SP>1</SP> - benz - 6:7<SP>1</SP> - trimethylene - thiazolino - thiacarbocyanine iodide, 3:2<SP>1</SP> - dimethyl - 6:9<SP>1</SP> - trimethylene - thiazolino-thiadicarbocyanine-iodide, and 3:2<SP>1</SP>-dimethyl - 6:7<SP>1</SP> - dimethylene - thiazolino - thiacarbocyanine bromide are similarly prepared. The dyes are sensitizers for silver halide (including chloride, bromide, and chlorobromide) emulsions, sensitizing data being given. Some impart red-sensitivity with little or no greensensitivity. # - N - (#<SP>1</SP> - cyclopentenyl) - aminoethyl alcohol is prepared by heating together #-aminoethyl alcohol and #<SP>1</SP>-cyclopentene-carboxylic acid. # - N - (#<SP>1</SP> - cyclohexenyl) - aminoethyl alcohol is similarly prepared. #<SP>1</SP>-cyclopentenecarboxylic acid is prepared by reacting cyclopentanone with KCN, treating with phosphorus pentoxide, and hydrolyzing with KOH. The corresponding anhydride is prepared by heating with acetic acid, and the corresponding acid halides are prepared by heating the acid with a thionyl halide, e.g. thionyl chloride. #<SP>1</SP> - cyclo - hexenecarboxylic acid and the corresponding anhydride and acid halides are similarly prepared. 1 - methylthiol - 4:5 - dimethoxybenzthiazole is prepared by heating 1:2-dimethoxy-4-brom-5- nitrobenzene with sodium disulphide, reacting the product with carbon disulphide and potassium hydroxide to form the potassium salt of 4:5-dimethoxybenzthiazole-mercaptan, and methylating by treatment with dimethyl sulphate. According to the Provisional Specification, compounds of formula wherein R 1 , R 2  and R 3  are the same or different and are H or hydrocarbon groups ; R 4 , R 5'  R 6  and R, are H or hydrocarbon groups or may form part of a saturated carbocyclic ring system ; X is S, Se, or O; and n is a positive integer greater than 1, are prepared by condensing the aminoalcohol with an acid of formula and treating the product with P 2 S 5 , P 2 Se 5 , or P 2 O 5 . Dyes are prepared from such intermediates by condensing with an alkyl or aralkyl quaternary salt of a heterocyclic nitrogen compound containing in the α- or γ-position to a heterocyclic nitrogen atom, a thioether or selenoether group (including an alkyl-, aralkyl-, or aryl-thioether group or a corresponding selenoether group) or a -(CH = CH) x NH 2  group, where x is 1, 2 or 3 (including N-acyl, N-aryl, and N-acylaryl substituted groups of this type).