PHOTOCHROMIC COMPOUNDS, PROCESS FOR THEIR PREPARATION AND THEIR USE IN POLYMERIC MATERIALS

Abstract: Photochromatic compounds belonging to the group of spiro-isoindolino-oxazines having general formula (I). These photochromatic compounds can be used in polymeric materials.

Description: PHOTOCHROMIC COMPOUNDS, PROCESS FORTHEIRPREPARATION AND THEIRUSE IN POLYMERIC MATERIALS The present invention relates to photochromatic compounds . 5 More specifically, the present invention relates to photochromatic compounds belonging to the group of spiro-isoindolino-oxazines, a process for their preparation and their use in polymeric materials. A further object of the present invention relates 10 to polymeric compositions containing said photochromatic compounds and the photochromatic articles obtained from their processing. Photochromatic compounds are substances which have the characteristic of reversibly changing colour and/or 15 degree of luminous transmission when exposed to solar or artificial light in the band ranging from UV to visible, or to some types of electromagnetic radiation, returning to their original state of colour and transmission when the initial light source is removed. There are numerous substances with photochromatic characteristics, which belong to various groups of both organic and inorganic compounds such as, for example, those described in the texts "Photochromism" , by G.H. Brown (Ed.), Vol. Ill of the Weissberger series "Techniques of Organic Chemistry", Wiley Interscience, New York (1971) and in "Photochromism: Molecules and Systems", by H. Duerr and H. Bouas-Laurent (Ed.), Vol. 40 of the series "Studies in Organic Chemistry" Elsevier (1990) . Among organic photochromatic compounds, those belonging to the groups of spiro-indolino-oxazines, spiro-pyrans and chromenes, are particularly known and used. The above compounds are capable of giving photochromatic characteristics to polymerized organic materials used, for example, in the production of lenses for eye-glasses, special inks, toys, and in many other applications. As an example, the following patents can be mentioned: USA 3 , 562 , 172 , USA 3 , 578 , 602 , USA 4 , 215 , 010, USA 4,342,668, USA 5,055,576, USA 5,110,922, USA 5,186,867, EP 146,135, EP 134,633, EP 141,407, EP 245,020, IT 1,223,348 and IT 1,238,694. Compounds belonging to the group of spiro-indo- 7219 lino-oxazines have, with respect to other known compounds such as, for example, compounds belonging to the group of spiro-pyrans, the advantage of having a much higher fatigue resistance when subjected to light and dark cycles and also have good colourability characteristics . The Applicant has now found photochromatic compounds belonging to the group of spiro-isoindolino- oxazines which have excellent photochromatic character- istics and excellent fatigue resistance. In addition, these photochromatic compounds, unlike the known spiro- indolino-oxazines and spiro-isoindolino-oxazines, have a dark green colouring. The present invention therefore relates to photo- chromatic compounds belonging to the group of spiro- isoindolino-oxazines having general formula (I) : (I) wherein: R represents a linear or branched C^C. Q alkyl -3- group, said alkyl group optionally substituted with 1-10 halogen atoms selected from fluorine, chlorine and bromine, or with C(X) 3 groups wherein X is selected from fluorine, chlorine and bromine, hydroxyl groups, linear or branched C 1 -C 6 alkoxyl groups, carboxyl groups, cyano groups, or with a 2 , 2 , 6 , 6-tetramethylpiperidine group; a vinyl group; an allyl or methallyl group; a linear or branched C 2 -C 6 alkenyl group; an aryl group select- ed from phenyl , diphenyl and naphthyl , said aryl group optionally substituted with linear or branched C 1 -C 6 alkoxyl groups, carboxyl groups, amine groups, N,N-dialkyl (C,-C 6 ) amine groups; a COOR' ester group wherein R' represents a linear or branched C,,-C 10 alkyl group; a benzyl group, said benzyl group optionally substituted with 1-5 halogen atoms selected from fluorine, chlorine and bromine, or with C (X) 3 groups wherein X is selected from fluorine, chlorine and bromine, hydroxyl groups, linear or branched ^-C^ alkyl groups, linear or branched C 1 -C 6 alkoxyl groups, carboxyl groups, cyano groups, or with a 2 , 2 , 6 , 6-tetramethylpiperidine group; R 1 and R 2 , the same or different, represent a linear or branched C, | -C 10 alkyl group, said alkyl -4- group optionally substituted with 1-10 halogen atoms selected from fluorine, chlorine and bromine, or with C(X) 3 groups wherein X is selected from fluorine, chlorine and bromine, hydroxyl groups, linear or branched C 1 -C 6 alkoxyl groups, carboxyl groups, cyano groups, or with a 2,2,6,6- tetramethylpiperidine group; a vinyl group; an allyl or methallyl group; a linear or branched C 2 -C 10 alkenyl group; a COOR' ester group wherein R' represents a linear or branched C.,-C 10 alkyl group; a benzyl group, said benzyl group optionally substituted with 1-5 halogen atoms selected from fluorine, chlorine and bromine, or with C(X) 3 groups wherein X is selected from fluorine, chlorine and bromine, hydroxyl groups, linear or branched C,,-C 10 alkyl groups, linear or branched C 1 -C 6 alkoxyl groups, carboxyl groups, cyano groups, or with a 2 , 2 , 6, 6-tetramethylpiperidine group; a linear or branched C 1 -C 6 alkoxyl group; an N-alkyl (C,-C 6 ) amine group; an N,N-dialkyl (C,-C 6 ) amine group; or R 1 and R 2 , considered jointly with the carbon atom to which they are bound, represent a C 4 -C 10 cycloalkyl group, said cycloalkyl group optionally substituted with halogen atoms selected from fluorine, chlorine and bromine, or with hydroxyl groups, linear or branched C 1 -C 6 alkoxyl groups, carboxyl groups, cyano groups, amine groups, N-alkyl (C 1 -C 6 ) amine groups, N,N-dialkyl (C 1 -C 6 ) amine groups; a N,N-dialkyl (C 1 -C 6 ) amide group; an aryl group selected from phenyl and biphenyl ; a cyano group; R 3 , R 4 , R 5 , R 6 R 8 , R 9 , R 10 , R , R 12 and R 13 , the same or different, represent a hydrogen atom; a halogen atom selected from fluorine, chlorine, bromine and iodine; a linear or branched C 1 -C 6 alkyl group, said alkyl group optionally substituted with 1-6 halogen atoms selected from fluorine, chlorine and bromine, or with C(X) 3 groups wherein X is selected from fluorine, chlorine and bromine, hydroxyl groups, linear or branched C 1 -C 6 alkoxyl groups, carboxyl groups, cyano groups, or with a 2,2,6,6- tetramethylpiperidine group; a benzyl group, said benzyl group optionally substituted with 1-5 halogen atoms selected from fluorine, chlorine and bromine, or with C(X) 3 groups wherein X is selected from fluorine, chlorine and bromine, hydroxyl groups, linear or branched C^C^ alkyl groups, linear or branched C 1 -C 6 alkoxyl groups, carboxyl groups, cyano groups, or with a 2 , 2 , 6 , 6-tetrame- thylpiperidine group; a hydroxyl group; a linear -6- or branched C 1 -C 6 alkoxyl group; an amine group; an N-alkyl (C 1 -C 6 ) amine group; an N,N-dialkyl (C 1 -C 6 ) amine group; a piperidine, piperazine or morpho- line group; a C 1 -C 6 carboxyalkyl group; a C 2 -C 6 carboxyalkenyl group; a carboxyamide group; an N- alkyl (C,-C 6 ) carboxyamide group; an N,N-dialkyl (C 1 -C 6 ) carboxyamide group; a cyano group; a nitro group; a sulfonic group; an aryl group selected from phenyl , biphenyl and naphthyl , said aryl group optionally substituted with N,N-dialkyl (C,-C 6 ) amine groups, linear or branched C 1 -C 6 alkoxyl groups, hydroxyl groups, linear or branched C 1 -C 6 alkyl groups; an acyl group of the alkyl ketone, aryl ketone or benzyl ketone type; a linear or branched C 2 -C 6 alkenyl group, said alkenyl group optionally subsituted with one or two N,N-dialkyl- (C 1 -C 6 ) -4 -aniline groups; an N-2 , 3- dihydroindoline group; a linear or branched C 1 -C 6 thioether group; two consecutive substituents between R 3 and R 6 , between R 8 and R ? and between R 10 and R 13 , can represent the condensation points with other aromatic, heterocyclic or quinone rings; R 7 represents a hydrogen atom; a halogen atom selected from fluorine, chlorine and bromine; a linear or branched C 1 -C 6 alkyl group; a linear or branched C 1 -C 6 alkoxyl group; a phenyl group; a phenoxyl group ; Z represents CH or a nitrogen atom; - Y represents an oxygen atom; a nitrogen atom; a sulfur atom; or a selenium atom. Preferred compounds having general formula (I) for the purposes of the present invention are those wherein: - R represents one of the following groups: methyl, ethyl, isopropyl, 2-allyl, 2-hydroxyethyl , 2-car- boxymethyl, phenyl, 4-N,N-dimethylaminoaniline, 4- methoxybenzene, 4-cyanobenzene; R 1 and R 2 , the same or different, represent a methyl or phenyl group; or considered jointly with the carbon atom to which they are bound, represent a cyclohexyl group; R 3 , R 4 , R 5 , R 6 , R 8 , R 9 , R 10 R^, R 12 and R 13 , the same or different, represent a hydrogen atom, a fluo- rine atom, a chlorine atom, a bromine atom, or one of the following groups: methyl, isopropyl, hydroxyl, methoxyl, N,N-dimethylamine, piperidine, mor- pholine, carboxyl, carboxymethyl , N, N-dimethyl - carboxyamide, cyano, nitro, methylketone, phenyl - ketone, phenyl; -8- R 7 represents a hydrogen atom, a chlorine atom, a bromine atom, a methyl group or a phenyl group; Z represents N; Y represents 0. Specific examples of preferred compounds of the present invention are: Compound having formula (la) : da) Compound having formula (lb) ( ib ; Compound having formula (Ic) -9- (Ic) Compound having formula (Id) (Id) A further object of the present invention relates to a process for the preparation of the photochromatic compounds having general formula (I) . The photochromatic compounds having general formula (I) can be prepared by the condensation of isoindoline compounds having general formula (II) : -10- R. (II R wherein the substituents from R to R 7 have the same meanings described above, with nitroso compounds having general formula (III) : (III) R' '0 wherein the substituents from R a to R 13 and Y have the same meanings described above and R' ' represents a sodium, potassium, lithium, rubidium or cesium atom. The condensation reaction between the isoindoline compounds having general formula (II) (Scheme 1 indicates the salts of these compounds, having general formula (II') , which are normally used) and the nitroso compounds having general formula (III) , illustrated in Scheme 1 : ■ 11- SCHEME 1 (I) wherein the substituents from R to R 13 , R' ' and Y have the same meanings described above and X represents a halogen atom such as, for example, chlorine, bromine or iodine, is carried out in the presence of an inert organic solvent such as, for example, acetone, ethyl alcohol, isopropanol, toluene, dioxane, or a mixture of these solvents, at a temperature ranging from 50 °C to 100°C, preferably from 60°C to 75°C, for a time ranging from 1 hour to 10 hours, preferably from 1 hour to 3 hours. The reaction product thus obtained is, generally, purified on a neutral column of active aluminum oxide 90 (activity degree I) , and subsequent crystalli- ■ 12- zation from a solvent such as, for example, acetone, toluene, pentane, heptane, diethyl ether. The isoindoline compounds having general formula (II) can be prepared according to processes known in the art and described, for example, in: "Tetrahedron" (1966), Vol. 22, page 2481; "Journal of Organic Chemistry" (1979), Vol. 44, page 1519; "Angewandte Chemie International (1968), Vol. 7, page 373. The isoindoline compounds having general formula (II) are usually conserved in the form of salts (isoindoline compounds having general formula (II') indicated in Scheme 1) such as, for example, iodides, bromides, chlorides, as the free base is very oxidable in air. The nitroso compounds having general formula (III) can be prepared by the reaction of phenol compounds with nitrous acid or butyl nitrite, as described, for example, in Italian patent 1,176,858. Specific examples of isoindoline compounds having general formula (II) , which can be used in the above process, are the following: 1,1,2,4, 7-pentamethyl-3 -methylene- isoindoline having formula (Ila) : •13- (Ha; 1,1,4, 7 -tetramethyl-N-phenyl -3-methylene- isoindoline having formula (lib) : 6 5 -CH 3 CH 2 (lib) ; 1,1,4, 7-tetramethyl-N-benzyl-3-methylene-isoindol- ine having formula (lie) : (He) 1,1,4, 7-tetramethyl-N- (2-chloroethyl) -3-methylene- •14- isoindoline having formula (lid) CH, (lid) CH 2 Cl In the process of the present invention, the salts of the above isoindoline compounds having general formula (Ila) - (lid) , are preferably used; even more preferably the iodine salts (iodides) of the above compounds .' A specific example of a nitroso compound having general formula (III) which can be used in the above process, is the following: sodium salt of l-nitroso-2-hydroxybenzofuran having formula (Ilia) : 8 7 β (Ilia) NaO The photochromatic compounds having general formula (I) of the present invention are colourless or ■ 15- slightly orange-coloured crystalline products. Their solutions in common organic solvents such as, for example, benzene, toluene, methanol, ethanol, when not exposed to light sources are colourless or slightly orange-coloured. These solutions, if exposed to a light source, either visible or ultraviolet, become green. The colouring quickly diminishes when the light source is removed. The photochromatic compounds having general formula (I) can be applied to the surface or incorporated in mass into the desired articles, using techniques already known in the art and described hereun- der. Some polymeric photochromatic end-articles can be obtained with moulding techniques such as, for example, injection or compression moulding, starting from polymers in which the photochromatic compound having formula (I) is homogeneously dispersed in mass. Alternatively, the photochromatic compound having general formula (I) can be dissolved in a solvent, together with the polymeric material such as, for example, polymethyl methacrylate, polyvinyl alcohol, polyvinyl butyral, cellulose acetate butyrate or epoxy, polysiloxane, urethane resin. The mixture thus obtained is deposited on a transparent support to form, after -16- evaporation of the solvent, a photochromatic coating. The photochromatic compound having general formula (I) can also be added to a polymerizable monomer such as, for example, a meth (acrylic) or allyl carbonate monomer, so that, after polymerization carried out in the presence of a suitable initiator such as, for example, azo-bis (isobutyronitrile) in the case of the meth (acrylic) monomer or a peroxyketal in the case of the allyl carbonate monomer, they are uniformly incor- porated in the resin formed. Finally, the photochromatic compound having general formula (I) can be applied to a transparent substrate such as, for example, polycarbonate, poly- methyl methacrylate or polydiethylene glycol bis (allyl carbonate) , by surface impregnation obtained by putting the substrate in contact, at a suitable temperature, with a solution or dispersion containing the photochromatic compound having general formula (I) , operating according to the method described, for example, in U.S. patent 5,130,353. The photochromatic compounds having general formula (I) of the present invention have the characteristic of being able to be incorporated in mass or using one of the techniques described above, into various organic polymers such as, for example, high -17- density polyethylene (HDPE) , low density polyethylene (LDPE) , ethylene-vinylacetate copolymer, polyether amides, polypropylene, polymethylmethacrylate, polyvinyl alcohol, polyvinyl butyral , cellulose acetate butyrate, epoxy, polysiloxane or urethane resins, polycarbonate, polydiethylene glycol bis (allyl carbonate) , polyamides, polyesters, polystyrene, vinyl polychloride, polyethylacrylate, siliconic polymers. A further object of the present invention there- fore relates to polymeric compositions comprising the above polymeric materials and the above photochromatic compounds having general formula (I) and the photochromatic articles obtained from their processing. The photochromatic compounds having general formula (I) of the present invention, are added to the above polymeric compositions in a quantity ranging from 0.01% to 5% by weight, preferably between 0.1% and 2% by weight, with respect to the weight of said polymeric compositions . The photochromatic compounds having general formula (I) of the present invention can also be added to coating compositions, such as for example, paints, lacquers, paints or lacquers based on hybrid polysil- oxanes and/or silica gel, compositions based on plastic materials. A further object of the present invention -18- consequently relates to coating compositions, such as for example, paints, lacquers, paints or lacquers based on hybrid polysiloxanes and/or silica gel, compositions based on plastic materials, comprising said photochrom- atic compounds. The photochromatic compounds having general formula (I) of the present invention are added to the above coating compositions in a quantity ranging from 0.01% to 5% by weight, preferably between 0.1% and 2% by weight, with respect to the weight of said coating compositions . Paints or lacquers based on hybrid polysiloxanes and/or silica gel are obtained by means of the "sol- gel" process described, for example, by M. Nogami , Y. Abe in: "Journal of Materials Science" (1995), Vol. 30, pages 5789-5792. The above coating compositions can be applied to the substrate (metal, plastic, wood, etc.) using the conventional methods such as, for example, brushing, spraying, pouring, dipping or electrophoresis . The photochromatic compounds having general formula (I) of the present invention can optionally be used in the presence of normal additives for organic polymers such as, for example, phenolic antioxidants, sterically hindered amines, benzotriazoles, benzophen- -19- 7219 ones, phosphites or phosphonites . The photochromatic compounds having general formula (I) of the present invention which, as already mentioned above, have a dark green colouring, can be used as such, mixed with each other, or combined with other suitable organic photochromatic compounds in order to obtain, after activation, the formation of other colourings such as brown and grey. For this purpose, photochromatic compounds belonging to the group of spiro-indolino-oxazines or spiro-pyrans described in the art such as, for example, in U.S. patent 5,066,818, are particularly useful for the purpose . The examples provided hereunder for a better understanding of the present invention and for its embodiment are purely illustrative and in no way limit the scope of the invention itself. EXAMPLE 1 Preparation of 1, 1, 2 , 4 , 7-pentamethyl-3- ethylene- isoindoline iodide having formula (II' a) : 6 5 ■ 20- 40 g of acetonylacetone, 12 g of methylamine hydrochloride, 20 ml of water and 12 ml of ethyl alcohol are charged into a 100 ml flask, equipped with a reflux cooler and mechanical stirrer. The above mixture is heated to 80 °C, under a nitrogen atmosphere, for 24 hours. At the end, the mixture is cooled and subsequently extracted with 30 ml of hexane . The aqueous phase obtained is treated with aqueous sodium hydroxide (solution at 30%) until pH 14 is reached: a yellow-white precipitate is thus formed which is rapidly filtered and washed with 30 ml of water and 10 ml of hexane. The product is dried under vacuum and conserved in a nitrogen atmosphere: the yield is 23.5 g. This product is identified as 1 , 2 , 3 , 4 , 7-pentamethyl- isoindoline, by gas-mass (molecular weight = 187) and NMR spectrum. A quantity equal to 23.5 g of the above product is placed in a 100 ml inox steel autoclave together with 20 ml of toluene and 21.4 g of methyliodide. The autoclave is heated to 85 °C and is maintained at this temperature, under a nitrogen atmosphere, for 6 hours. At the end, the autoclave is cooled to room temperature and the raw product is filtered obtaining a crystalline precipitate which is washed with 20 ml of ethyl acetate -21- and finally with 20 ml of hexane. 35 g of product are obtained, corresponding to 1,1,2,4, 7-pentamethyl-3-methylene-isoindoline iodide having formula (II' a) . The free base, corresponding to Compound (Ila) , is identified by gas-mass (molecular weight = 201) and the salt by NMR. The NMR data are indicated in Table 1. TABLE 1 1 H δ (ppm) CH 3 on Cl 1.74 NCH 3 3.83 CH 3 on C3 3.17 CH 3 on C4 2.46 CH 3 on C7 2.67 H5 7.17 H6 7.37 EXAMPLE 2 Preparation of 1, 1, 4, 7- tetramethyl-N-phenyl- 3-methylene- isoindoline iodide having formula (Il'b) . •22- Il ' b ) c 46 g of acetonylacetone, 26 g of aniline hydro- chloride, 20 ml of water and 12 ml of ethyl alcohol are charged into a 100 ml flask, equipped with a reflux cooler and mechanical stirrer. The above mixture is heated to 80 °C, under a nitrogen atmosphere, for 24 hours. At the end, the mixture is- cooled and subsequently extracted with 30 ml of hexane. The aqueous phase obtained is treated with aqueous sodium hydroxide (solution at 30%) until a pH 14 is reached: a yellow-white precipitate is thus formed which is rapidly filtered and washed with 30 ml of water and 20 ml of hexane. The product is dried under vacuum and conserved in a nitrogen atmosphere: the yield is 44 g. This product is identified as 1 , 3 , 4 , 7-tetramethyl-N-phenyl-isoindo- line, by gas-mass (molecular weight = 249) and NMR spectrum. A quantity equal to 25 g of the above product is placed in a 100 ml inox steel autoclave together with -23- 20 ml of toluene and 18 g of methyliodide. The autoclave is heated to 85 °C and is maintained at this temperature, under a nitrogen atmosphere, for 6 hours. At the end, the autoclave is cooled to room temperature and the raw product is filtered obtaining a crystalline precipitate which is washed with 20 ml of ethyl acetate and finally with 20 ml of hexane. 24 g of product are obtained, corresponding to 1,1,4, 7 -tetramethyl-N-phenyl- 3-methylene-isoindoline iodide having formula (II 'b) . The free base, corresponding to Compound (lib) , is identified by gas-mass (molecular weight = 263) and the salt by NMR. The NMR data are indicated in Table 2. TABLE 2 1 H δ (ppm) CH 3 on Cl 1.70 CH 3 on C3 3.02 CH 3 on C4 2.51 CH 3 on C7 2.74 H5 7.26 H6 7.46 Ha 7.65 Hb 7.72 He 7.61 -24- EXAMPLE 3 Preparation of 1, 1, 4, 7-tetramethyl-N-benzyl-3-methylene- isoindoline iodide having formula (II'c) . 7 — \ CH- CH ^ __ 4 C ^ \H3, \ 1 / + • ^ 3 1 + / ' CH (II'c) 77 g- of acetonylacetone, 48 g of benzylamine hydrochloride, 40 ml of water and 20 ml of ethyl alcohol are charged into a 250 ml flask, equipped with a reflux cooler and mechanical stirrer. The above mixture is heated to 80 °C, under a nitrogen atmosphere, for 20 hours. At the end, the mixture is cooled and subsequently extracted with 30 ml of toluene. The aqueous phase obtained is treated with aqueous sodium hydroxide (solution at 30%) until a pH 14 is reached: a yellow-white precipitate is thus formed which is rapidly filtered and washed with 30 ml of water and 20 ml of hexane. The product is dried under vacuum and conserved in -25- a nitrogen atmosphere: the yield is 65 g. This product is identified as 1 , 3 , 4 , 7-tetramethyl-N-benzyl-isoindo- line, by gas-mass (molecular weight = 263) and NMR spectrum. A quantity equal to 65 g of the above product is placed in a 200 ml inox steel autoclave together with 120 ml of acetonitrile and 43 g of methyliodide. The autoclave is heated to 80°C and is maintained at this temperature, under a nitrogen atmosphere, for 6 hours. At the end, the autoclave is cooled to room temperature and the raw product is filtered obtaining a crystalline precipitate which is washed with 20 ml of ethyl acetate and finally with 20 ml of hexane. 86 g of product are obtained, corresponding to 1,1,4, 7 -tetramethyl-N-benzyl -3-methylene-isoindoline iodide having formula (II'c). The free base, corresponding to Compound (lie) , is identified by gas-mass (molecular weight = 277) and the salt by NMR. The NMR data are indicated in Table 3.. -26- TABLE 3 1 H δ (ppm) CH 3 on Cl 1.82 CH 3 on C3 3.05 CH 3 on C4 2.49 CH 3 on C7 2.69 H5 7.26 H6 7.43 Ha 5.65 Hb 7.38 He 7.18 Hd 7.33 EXAMPLE 4 Preparation of 1, 1, 4, 7- tetramethyl-N-2 -chloroethyl -3' methylene-isoindoline iodide having formula (Il'd) . 6 5 CH, CH, -CH 3 (Il'd; b CH, Cl •27- 62 g of acetonylacetone, 31.6 g of chloro-ethyl- amine hydrochloride, 20 ml of water and 10 ml of ethyl alcohol are charged into a 100 ml flask, equipped with a reflux cooler and mechanical stirrer. The above mixture is heated to 80°C, under a nitrogen atmosphere, for 24 hours. At the end, the mixture is cooled and subsequently extracted with 60 ml of toluene. The aqueous phase obtained is treated with an excess of aqueous sodium carbonate (aqueous solution at 30%) until a pH 14 is reached: a precipitate is thus formed which is rapidly filtered and washed with 30 ml of water and 10 ml of hexane. The product is dried under vacuum and conserved in a nitrogen atmosphere: the yield is 58 g. This product is identified as 1, 3 , 4 , 7-tetramethyl-N-2-chloroethyl-3- methylene-isoindoline, by gas-mass (molecular weight = 235.5) and NMR spectrum. A quantity equal to 58 g of the above product is placed in a 200 ml inox steel, autoclave together with 40 ml of toluene and 42 g of methyliodide. The autoclave is heated to 85 °C and is maintained at this temperature, under a nitrogen atmosphere, for 13 hours. At the end, the autoclave is cooled to room temperature and the raw product is filtered obtaining a crystalline precipitate which is washed with 20 ml of ethyl acetate -28- and finally with 20 ml of hexane. 85 g of product are obtained, corresponding to 1,1,4, 7-tetramethyl-N-2-chloroethyl-3-methylene-isoind- oline iodide having formula (Il'd). The free base, corresponding to Compound (lid), is identified by gas- mass (molecular weight = 249.5) and the salt by NMR. The NMR data are indicated in Table 4. TABLE 4 1 H δ (ppm) CH 3 on Cl 1.87 CH 3 on C3 3.25 CH 3 on C4 2.48 CH 3 on C7 2.70 H5 7.26 H6 7.42 Ha 4.11 Hb 4.78 EXAMPLE 5 Preparation of the Compound having formula (la) 6 5 8' (la) ■ 29- 3.6 gof 1,1,2,4, 7-pentamethyl -3-methylene-isoindoline iodide obtained as described in Example 1, 2.6 g of the sodium salt of l-nitroso-2-hydroxydibenzofuran and 40 ml of acetone are charged into a 100 ml flask, equipped with a reflux cooler and mechanical stirrer. The above mixture is heated to 60 °C and maintained at this temperature, under stirring, under a nitrogen atmosphere, for 1 hour. The reaction raw product obtained is filtered and subsequently purified by passage on a neutral column of active aluminum oxide 90 (activity degree I) , eluating with a mixture of heptane/ethyl acetate in a ratio of 98/2. An almost pure photochromatic product is obtained which is further purified by crystallization from toluene. After crystallization, 2 g of an almost white product are obtained, corresponding to the Compound having formula (la) which is identified by gas-mass (molecular weight = 396) and NMR spectrum. The NMR data are indicated in Table 5. •30- TABLE 5 1 H δ (ppm) CH 3 on Cl 1.57-1.58 CH 3 on N 2.30 CH 3 on C4 2.30 CH 3 on C7 2.50 Cl -- C3 -- H2' 7.54 H5 7.07 H6 7.14 H5' 6.97 H6' 7.38 ■ H7' 7.57 H8' 7.39 H9' 7.47 H10' 8.53 EXAMPLE 6 Preparation of the Compound having formula (lb) lb) C -31- 4 g of 1, 1, 4, 7-tetramethyl-N-phenyl-3-methylene- isoindoline iodide obtained as described in Example 2, 2.4 g of the sodium salt of 1 -nitroso-2 -hydroxydibenzo- furan and 40 ml of acetone are charged into a 100 ml flask, equipped with a reflux cooler and mechanical stirrer. The above mixture is heated to 60 °C and maintained at this temperature, under stirring, under a nitrogen atmosphere, for 2 hours. The reaction raw product obtained is filtered and subsequently purified by passage on a neutral column of active aluminum oxide 90 (activity degree I) , eluating with a mixture of hept- ane/dichlόro methane in a ratio of 1/1. An almost pure photochromatic product is obtained which is further purified by crystallization from toluene . After crystallization, 1.8 g of an almost white product are obtained, corresponding to the Compound having formula (lb) which is identified by gas-mass (molecular weight = 458) and NMR spectrum. The NMR data are indicated in Table 6. •32- TABLE 6 1 H δ (ppm) CH-, on Cl 1.52-1.65 CH,. on C4 2.25 CH,. on C7 2.50 Cl C3 H2' 7.62 H5 7.12 H6 7.20 H5' 6.94 H6' 7.27 H7' 7.46 H8' 7.20 H9' 7.38 H10' 8.24 Ha 7.20 Hb 7.00 He 6.92 EXAMPLE 7 Preparation of the Compound having formula (Ic) 6 5 8' (Ic) ■ 33 4.4 g of 1,1,4, 7 -tetramethyl-N-benzyl- 3 -methylene- isoindoline iodide obtained as described in Example 3, 2.55 g of the sodium salt of l-nitroso-2-hydroxydi- benzofuran and 60 ml of acetone are charged into a 100 ml flask, equipped with a reflux cooler and mechanical stirrer. The above mixture is heated to 60 °C and maintained at this temperature, under stirring, under a nitrogen atmosphere, for 2 hours. The reaction raw product obtained is filtered and subsequently purified by passage on a neutral column of active aluminum oxide 90 (activity degree I) , eluating with a mixture of hept- ane/dichlo ' romethane in a ratio of 1/1. An almost pure photochromatic product is obtained which is further purified by crystallization from pentane . After crystallization, 3.2 g of an almost white product are obtained, corresponding to the Compound having formula (Ic) which is identified by gas-mass (molecular weight = 472.6) and NMR spectrum. The NMR data are indicated in Table 7. • 34- TABLE 7 1 H δ (ppm) CH 3 on Cl 1.59-1.61 CH, on C4 2.21 CH, on C7 2.51 Cl C3 H2' 7.37 H5 7.06 H6 7.16 H5' 6.94 H6' 7.36 H7' 7.56 H8' 7.30 H9' 7.46 H10' 8.13 a ' (CH-. on N) 3.82 - 4.08 Hb 7.01 He 6.95 Hd 7.07 EXAMPLE 8 Preparation of the Compound having formula (Id) 6 5 8' (Id) -35- 3 g of 1,1, 4, 7-tetramethyl-N-2 -chloroethyl-3- methylene-isoindoline iodide obtained as described in Example 4, 2.1 g of the sodium salt of l-nitroso-2- hydroxydibenzofuran and 40 ml of acetone are charged into a 100 ml flask, equipped with a reflux cooler and mechanical stirrer. The above mixture is heated to 70 °C and maintained at this temperature, under stirring, under a nitrogen atmosphere, for 1 hour. The reaction raw product obtained is filtered and subsequently purified by passage on a neutral column of active aluminum oxide 90 (activity degree I) , eluating with a mixture of heptane/ethyl ' acetate in a ratio of 1/1. An almost pure photochromatic product is obtained which is further purified by crystallization from pentane . After crystallization, 0.8 g of an almost white product are obtained, corresponding to the Compound having formula (Id) which is identified by gas-mass (molecular weight = 445) and NMR spectrum. The NMR data are indicated in Table 8. -36- 7219 TABLE 8 1 H δ (ppm) CH 3 on Cl 1.59-1.62 CH, on C4 2.20 CH, on C7 2.44 Cl -- C3 -- H2' 7.50 H5 7.06 H6 7.12 H5' 6.94 H6' 7.40 H7' 7.58 H8' 7.38 H9' 7.49 H10' 8.50 a (CH P on N) 3.20 b (CH 2 on Cl) 3.40 1 EXAMPLE 9 Evaluation of the photochromatic activity. The photochromatic activity is evaluated in ethanol, at 25°C, of Compounds (la) - (Id) obtained as described in Examples 5-8. Solutions are prepared at a concentration equal to about 10 "4 M of the various Compounds (la) - (Id) in ethanol and subsequently 2 ml of each solution are placed in a quartz cell with an optical path of 1 cm. The quartz cell containing the solution is introduced into a temperature control system, equipped with ■ 37- a magnetic stirrer (the solution is maintained under stirring during the measurement) . The spectrum of the activated and deactivated forms and the decolouring kinetics are registered with a UV/visible spectropho- tometer with a photodiode detector (HP 8453) equipped with perpendicular optical fibres which give a continuous monochromatic irradiation. The light source is a high pressure Hg lamp and the irradiation wave length is determined by monochromatic filters. This system allows the absorbance to be contemporaneously monitored at all wave-lengths. The following parameters are determined using the measurements obtained as described above and with a calculation effected with the GRAFit program of Erith- aeus Software Ltd. for the mathematical treatment of the graphs : t 1/2 (s) : time in which the absorbance reaches a value equal to half of the initial absorbance value ; - k Δ (s "1 ) : constant of the ring closing thermal reaction rate; λ PMC (nm) : wave-length of the maximum absorbance of the merocyaninic open form; colorability: difference between the final absor- bance and initial absorbance. -38- The data obtained are indicated in Table 9 TABLE 9 Compound λ PMC t 1/2 Colora- (s) (s- 1 ) (nm) bility (la) 400 1.7X10 "3 446.645 0.1 (lb) * * 461.661 * (Ic) 240 2.3X10 "3 473.662 0.05 (Id) * * 470.659 * the samples analyzed return too quickly to the initial state and at 25°C it was not possible to evaluate the photochromatic activity; the measuring of the photochromatic activity, in this case, must be evaluated by slowly lowering the temperature to 0°C; in fact, compounds (lb) and (Id) have a green colouring when irradiated at 0°C. -39-

Claims: CLAIMS 1. Photochromatic compounds belonging to the group of spiro-isoindolino-oxazines having general formula (I) : (I wherein: R represents a linear or branched C^C^ alkyl group, said alkyl group optionally substituted with 1-10 halogen atoms selected from fluorine, chlorine and bromine, or with C(X) 3 groups wherein X is selected from fluorine, chlorine and bromine, hydroxyl groups, linear or branched C 1 -C 6 alkoxyl groups, carboxyl groups, cyano groups, or with a 2,2,6,6- tetramethylpiperidine group; a vinyl group; an allyl or methallyl group; a linear or branched C 2 -C 6 alkenyl group; an aryl group selected from phenyl, biphenyl and naphthyl , said aryl group optionally substituted with -40- linear or branched C 1 -C 6 alkoxyl groups, carboxyl groups, amine groups, N,N-dialkyl (C 1 -C 6 ) amine groups; a COOR' ester group wherein R' represents a linear or branched 5 c ι -C ιo a lkyl group; a benzyl group, said benzyl group optionally substituted with 1-5 halogen atoms selected from fluorine, chlorine and bromine, or with C(X) 3 groups wherein X is selected from fluorine, chlorine and 10 bromine, hydroxyl groups, linear or branched J-CJ Q alkyl groups, linear or branched C 1 -C 6 alkoxyl groups, carboxyl groups, cyano ' groups, or with a 2 , 2 , 6, 6-tetramethylpiperid- ine group; 15 - R 1 and R 2 , the same or different, represent a linear or branched C^C^ alkyl group, said alkyl group optionally substituted with 1-10 halogen atoms selected from fluorine, chlorine and bromine, or with C(X) 3 groups where- 20 in X is selected from fluorine, chlorine and bromine, hydroxyl groups, linear or branched C 1 -C 6 alkoxyl groups, carboxyl groups, cyano groups, or with a 2,2,6, 6-tetramethylpiperid- ine group; a vinyl group; an allyl or meth- 25 allyl group; a linear or branched C 2 -C 10 -41- alkenyl group; a COOR' ester group wherein R' represents a linear or branched CJ-CJ Q alkyl group; a benzyl group, said benzyl group optionally substituted with 1-5 halogen atoms 5 selected from fluorine, chlorine and bromine, or with C(X) 3 groups wherein X is selected from fluorine, chlorine and bromine, hydroxyl groups, linear or branched C.,-C 10 alkyl groups, linear or branched C 1 -C 6 alkoxyl 10 groups, carboxyl groups, cyano groups, or with a 2 , 2 , 6, 6-tetramethylpiperidine group; a linear or branched C 1 -C 6 alkoxyl group; an N-alkyl (C,-C 6 ) amine group; an N,N-dialkyl (C,-C 6 ) amine group; or R 1 and R 2 , considered 15 jointly with the carbon atom to which they are bound, represent a C 4 -C 10 cycloalkyl group, said cycloalkyl group optionally substituted with halogen atoms selected from fluorine, chlorine and bromine, or with hy- 20 droxyl groups, linear or branched C 1 -C 6 alkoxyl groups, carboxyl groups, cyano groups, amine groups, N-alkyl (C,-C 6 ) amine groups, N,N-dialkyl (C 1 -C 6 ) amine groups; a N,N-dial- kyl (C 1 -C 6 ) amide group; an aryl group select - 25 ed from phenyl and biphenyl; a cyano group; -42- R 3 , R 4 , R j , R 6 R g , R 9 , R-|o' 11 ' ^ 12 an< - ^ 13 ' the same or different, represent a hydrogen atom; a halogen atom selected from fluorine, chlorine, bromine and iodine; a linear or 5 branched C,-C 6 alkyl group, said alkyl group optionally substituted with 1-6 halogen atoms selected from fluorine, chlorine and bromine, or with C(X) 3 groups wherein X is selected from fluorine, chlorine and bromine, hydroxyl 10 groups, linear or branched C 1 -C 6 alkoxyl groups , carboxyl groups , cyano groups , or with a 2 , 2 , 6, 6-tetramethylpiperidine group; a benzyl group, said benzyl group optionally substituted with 1-5 halogen atoms selected 15 from fluorine, chlorine and bromine, or with C(X) 3 groups wherein X is selected from fluorine, chlorine and bromine, hydroxyl groups, linear or branched C^C^ alkyl groups, linear or. branched C 1 -C 6 alkoxyl 20 groups, carboxyl groups, cyano groups, or with a 2 , 2 , 6, 6-tetramethylpiperidine group; a hydroxyl group; a linear or branched C 1 -C 6 alkoxyl group; an amine group; an N-alkyl (C 1 -C 6 ) amine group; an N,N-dialkyl (C 1 -C 6 ) 25 amine group; a piperidine, piperazine or -43- morpholine group; a C,-C 6 carboxyalkyl group; a C 2 -C 6 carboxyalkenyl group; a carboxyamide group; an N-alkyl (C 1 -C 6 ) carboxyamide group; an N,N-dialkyl (C 1 -C 6 ) carboxyamide group; a 5 cyano group; a nitro group; a sulfonic group; an aryl group selected from phenyl, biphenyl and naphthyl, said aryl group optionally substituted with N,N-dialkyl (C 1 -C 6 ) amine groups, linear or branched C 1 -C 6 alkoxyl 10 groups, hydroxyl groups, linear or branched C 1 -C 6 alkyl groups; an acyl group of the alkyl ketone, aryl ketone or benzyl ketone type; a linear or branched C 2 -C 6 alkenyl group, said alkenyl group optionally subsituted with one 15 or two N,N-dialkyl (C,-C 6 ) -4-aniline groups; an N-2, 3-dihydroindoline group; a linear or branched C 1 -C 6 thioether group; two consecutive substituents between R 3 and R 6 , between R 8 and R, and between R 10 and R 13 , 20 can represent the condensation points with other aromatic, heterocyclic or quinone rings ; R 7 represents a hydrogen atom; a halogen atom selected from fluorine, chlorine and bromine; 25 a linear or branched C,-C 6 alkyl group; a -44- linear or branched C 1 -C 6 alkoxyl group; a phenyl group; a phenoxyl group; Z represents CH or a nitrogen atom; Y represents an oxygen atom; a nitrogen atom; a sulfur atom; or a selenium atom. 2. The photochromatic compounds belonging to the group of spiro-isoindolino-oxazines having general formula (I) according to claim 1, wherein: R represents one of the following groups: methyl, ethyl, isopropyl, 2 -allyl, 2-hydroxy- ethyl, 2-carboxymethyl, phenyl, 4-N,N-dime- thylaminoaniline, 4-methoxybenzene, 4-cyano- benzene ; R 1 and R 2 , the same or different, represent a methyl or phenyl group; or considered jointly with the carbon atom to which they are bound, represent a cyclohexyl group; R 3 , R 4 , R 5 , R 6 , R 8 , R ? , R 10 R^, R 12 and R 13 , the same or different, represent a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, or one of the following groups: methyl, isopropyl, hydroxyl, methoxyl, N,N-dimethyl- amine, piperidine, morpholine, carboxyl, carboxymethyl, N,N-dimethylcarboxyamide, cyano, nitro, methylketone, phenylketone, -45- phenyl ; R 7 represents a hydrogen atom, a chlorine atom, a bromine atom, a methyl group or a phenyl group ; Z represents N; Y represents 0. A photochromatic compound belonging to the group of spiro-isoindolino-oxazines having general formula (I) according to claim 1 or 2 , consisting of the compound having formula (la) : (la) . A photochromatic compound belonging to the group of spiro-isoindolino-oxazines having general formula (I) according to claim 1 or 2 , consisting of the compound having formula (lb) : (lb) -46- A photochromatic compound belonging to the group of spiro-isoindolino-oxazines having general formula (I) according to claim 1 or 2 , consisting of the compound having formula (Ic) : ( ic : A photochromatic compound belonging to the group of spiro-isoindolino-oxazines having general formula (I) according to claim 1 or 2 , consisting of the compound having formula (Id) : (Id) 7. A process for the preparation of the photochromatic compounds belonging to the group of spiro- isoindolino-oxazines having general formula (I) -47- according to any of the previous claims, comprising the condensation of isoindoline compounds having general formula (II) : R- (II) R wherein the substituents from R to R ? have the same meanings defined above, with nitroso compounds having general formula (III) : R 11 (III) R' τ 0 wherein the substituents from R 8 to R 13 and Y have the same meanings described above and R' ' represents a sodium, potassium, lithium, rubidium or cesium atom. A process for the preparation of the photochromatic compounds belonging to the group of spiro- isoindolino-oxazines having general formula (I) • 48- according to any of the claims from 1 to 6 , comprising the condensation of salts of the isoindoline compounds having general formula (II) having general formula (II') with nitroso compounds having general formula (III) illustrated in Scheme 1 : SCHEME 1 (I) • wherein the substituents from R to R 13 , R' ' and Y have the same meanings described above and X represents a halogen atom such as chlorine, bromine or iodine, carried out in the presence of an inert organic solvent, or a mixture of these solvents, at a temperature ranging from 50°C to -49- 100°C, for a time ranging from 1 hour to 10 hours. 9. The process according to claim 8, wherein the inert organic solvent is selected from acetone, ethyl alcohol, isopropanol, toluene, dioxane . 10. The process according to claim 8 or 9, wherein the reaction temperature is between 60 °C and 75 °C. 11. The process according to claim 8, 9 or 10, wherein the reaction time is between 1 hour and 3 hours. 12. Polymeric compositions comprising at least one photochromatic compound belonging to the group of spiro-isoindolino-oxazines having general formula (I) according to any of the claims from 1 to 11, and at least one organic polymer selected from high density polyethylene, low density polyethyl- ene, ethylene-vinylacetate copolymer, polyether amides, polypropylene, polymethyl methacrylate, polyvinyl alcohol, polyvinyl butyral , cellulose acetate butyrate, epoxy, polysiloxane or urethane resins, polycarbonate, . polydiethylene glycol bis (allyl carbonate), polyamides, polyesters, polystyrene, vinyl polychloride, polyethylacryl- ate, siliconic polymers. 13. Coating compositions, such as paints, lacquers, paints or lacquers based on hybrid polysiloxanes and/or silica gel, compositions based on plastic -50- materials, comprising the photochromatic compounds belonging to the group of spiro-isoindolino- oxazines having general formula (I) according to any of the claims from 1 to 11. 14. The polymeric compositions according to claim 12 or 13, comprising additives for organic polymers selected from phenol antioxidants, sterically hindered amines, benzotriazoles, phosphites or phosphonites . 15. Photochromatic articles obtained from the processing of the compositions according to claims 12, 13 or 14. 16. Mixtures comprising at least one photochromatic compound belonging to the group of spiro-isoindol- ino-oxazines having general formula (I) according to any of the claims from 1 to 11 and at least one photochromatic compound belonging to the group of spiro-indolino-oxazines or spiro-pyrans . -51-

Inventors: DENIEL MARIE-HELENE, MALATESTA VINCENZO, SALEMI-DELVAUX CHRISTIANE, DENIEL, MARIE-HELENE, MALATESTA, VINCENZO, SALEMI-DELVAUX, CHRISTIANE
Applicants: DENIEL MARIE HELENE, GREAT LAKES CHEMICAL EUROP, MALATESTA VINCENZO, SALEMI DELVAUX CHRISTIANE, DENIEL, MARIE-HELENE, GREAT LAKES CHEMICAL (EUROPE) GMBH, MALATESTA, VINCENZO, SALEMI-DELVAUX, CHRISTIANE
Application year: 1999
Main classification: C09K9
IPC codes: C07D498, C09K9, G03C1