DE19515371C2 - Photochromic spirooxazine compounds - Google Patents

Description

The invention relates to photochromic spirooxazine compounds.

Spirooxazines have compared to other photochromic ver high long-term stability. Probably also from that Therefore, there is no other class of photochromic compounds has been processed as intensively as the last 25 years the indolinospironaphthoxazines to which the invention Spirooxazine compounds belong. This is not expressed last in a big one  Number of patent applications, some of which are connections themselves, some of their applications.

The basic body of the spirooxazine compounds is be already described in U.S. Patents 3,578,602 and 3,562,172 ben; in these publications only Ver described bonds that only substituents on Have indoline subsystem.

In the publications EP 245.020 A1, EP 134.633 A1, US-PS 4,215,010 and US Pat. No. 4,342,668 are then also substituents specified on other subsystems. Furthermore are benzo-fused or aza-substituted indoline or naphthalene subsystems have been described; here to EP 141.407 A1, in which the substituent Quinoline is called, or on EP 232.295 A1 referenced in which the substituent isoquinoline called is.

This class provides dyes that are under light color deep red to teal. Along with Dyes from the class of naphthopyrans, the yellow up to orange-red shades can do the whole thing visible spectrum are covered. To achieve cosmetically appealing neutral colors, such as gray or brown, from photo colored with these dyes chrome plastic eyeglass lenses is therefore one Mix of representatives of these two classes chatting.

According to the invention it has been recognized that a decision important role for the properties of photochromic glasses glasses and in particular their long-term stability Behavior in high vacuum during the anti-reflective treatment plays.  

Above all, there is a low tendency to migrate of the photochromic dyes even at high temperatures to promote.

The invention has for its object photochromic Specify spirooxazine compounds, even at high Temperatures and / or in vacuum a low Migra tend to have.

The achievement of this task is in Claim specified.

The invention is based on the knowledge that it Introduction of special substituents is possible or the photochromic dyes better in the polymer too fix, d. H. drastically reduce the tendency to migrate put.

This happens with polycyclic ring systems, such as for example Adamantan or Campher, through the steri hindrance due to the bulky substituents Substituents that have groups similar to the poly mer, however, by the interaction with the polymer.

The invention is described in more detail below:

The compounds according to the invention are spirooxazine compounds and in particular specially substituted indolinospiro naphthoxazines with the general structure

mean here

• - R ₁ , R ₂ , R ₃ and R ₄ independently of one another: H, halogen, G, OG, NG ₂ or OT,
• - R ₅ , R ₆ and R ₇ independently of one another: G,
• - R ₈ : H, NG ₂ or 1-piperidyl and
• - R ₉ , R ₁₀ independently of one another: H, halogen, G, OG or OT,
  in which
• G is a C ₁ -C ₆ alkyl, C ₅ -C ₇ cycloalkyl, phenyl, naphthyl or benzyl group,
• - At least one of the substituents R ₁ to R ₄ , R ₉ or R _{10 is} one of the groups -O-phenyl, -O-benzyl or -OT and
• - T either an adamantane, camphor, norbornane [2.2.1] -, Pinan [3.3.1] -, norcaran [4.1.0] -, tricyclene, 1-azabi cyclo [2.2.2] octane or 3-azabicyclo [3.2.2.] nonane residue or one of the following groups:

- (CH ₂ ) _n -O- (CH ₂ ) _m -CH ₃ , - (CH ₂ ) _n -O- (CH ₂ ) _n -O- (CH ₂ ) _m -CH ₃ ,

with n = 1, 2, 3, 4 and m = 0, 1, 2, 3.  

Bulky residues such as the polycyclic ring mentioned systems also offer the advantage that 2.6- Alkoxynaphthalenes known dimerization under light to prevent exposure. This occurs due to the very high dye concentrations in the surface dye exercise in plastic materials. Even minor ones Migration leads to the long period of use of the glasses to a noticeable loss of photochromic performance. This is also due to the training according to the invention increases the service life.

Examples of the polycyclic aliphatic ring system are Adamantan, Camphor, Norbornan etc.

Possible synthetic routes are described below:  

Synthetic route A

The compounds according to the invention are synthesized in a manner known per se, starting from 2,6- or 2,7-dihydroxynaphthalene. One hydroxyl group is esterified (protected) by benzoylation, the second is subsequently etherified with an alkyl halide, preferably iodide or bromide. The ester is then alkaline saponified again to form the free hydroxyl group. After nitrosation in the 1-position to the free hydroxyl group, the photochromic compound is synthesized as naphthoxazine by reaction with an active methylene indole base (substituted Fischer's base). In this step, if desired, the substituent R ₈ is also introduced simultaneously via the condensing agent.

Below is the synthesis using an example exem Plarely described. The different fiction moderate connections are in the same way by the Obtain use of the corresponding alkyl halides:

1. Synthesis of 6-benzoyloxy-2-naphthol

75 g of commercially available 2,6-dihydroxynaphthalene are in a 2 l Three-neck flask in 450 ml freshly distilled off over Na Dioxane dissolved with stirring and heating. Then 150 ml of freshly distilled benzoyl chloride and then 33 ml of freshly distilled pyridine added. Under strong Stirring will result in the mixture separating into two phases NEN tried to reflux for 4 h.

The hot mixture is poured into 10 l of cold water and further stirred. The failed mono- and diesters are filtered off, washed with hot water and dried. By boiling in 500 ml of ethanol for 5 minutes, the majority of the monoester is dissolved. The solution is filtered hot, the diester remaining as a residue is washed out with hot alcohol. The monoester is precipitated by diluting the alcoholic solution with 10 times the amount of 2% NaHCO ₃ solution. This is filtered off, washed and dried at 120 ° C (12 min). Repeated recrystallization from toluene gives the product (81 g) in colorless leaflets:
M.p .: 190-191 ° C.

2. Reaction with phenacyl bromide (halide)

25.5 g of the benzoic acid ester from 1 are triturated as intimately as possible with 19.9 g of phenacyl bromide and 14.0 g of anhydrous potassium carbonate. This mixture is suspended in 150 ml of dry acetone and refluxed for 3 hours. The solution is filtered. After the acetone has been stripped off from the filtrate, it is taken up in CH ₂ Cl ₂ , and unreacted naphthol is extracted from the filtrate with dilute NaOH. The organ. Phase is dried, filtered and the solvent is stripped off. Aceto phenone formed as a by-product remains in solution in the next synthesis step and is thus separated off.

3. Cleavage of the ester

The ester is split off by boiling in aqueous alcoholic KOH for 3 minutes, the naphthol is precipitated by acidifying the alkaline solution with dilute acetic acid and filtered off. After washing with dilute NaHCO ₃ solution to remove adhering benzoic acid residues, the product is dried. It is used without further cleaning.

4. Nitrosation of the ether

42 g of finely ground 6-phenacyloxy-2-naphthol are suspended in 400 ml of glacial acetic acid and 80 ml of water while cooling with ice. 11 g NaNO ₂ are added in one addition, 0.5 further grams after 10 min. The mixture is stirred for 2 h and then the precipitated mass is filtered off. This is washed out with aqueous dilute acetic acid and then with water. The light ocher colored product is used without further cleaning.

5. Implementation with Fischer's base

23.1 g of nitroso product from 4. are dissolved in 15 ml of 1,3,3-trimethyl-2-methylene-5-methoxy-indoline and with 10 drops of piperidine in 250 ml of ethanol and boiled under reflux for 4 h. The amount is concentrated to half volume in vacuo and allowed to cool. The precipitated crystal masses are filtered off and columned with ethanol on Al ₂ O ₃ . The fractions that turn turquoise blue under UV light are collected. After the ethanol has been stripped off, a little acetone is poured over and the mixture is left covered. After 4 days, the precipitated crystals are filtered off and washed in ethanol. The product, a fine yellow powder, could be identified by NMR analysis as spiro (5-methoxyindoline-2,3'-8'-phenacyloxy-naphth [2,1-b] oxazine).

If R _{8 is} not to be H but an amine function, this residue is introduced in a one-pot reaction via the condensing agent. For this purpose, 2 to 3 times the molar amount of secondary amine, for example piperidine, dibutylamine, dicyclohexylamine or the like, is used instead of the above amounts. For the introduction of the radical O-benzyl, O-phenyl or OT at R ₁₀ instead of R ₉ , 2,7- instead of 2,6-dihydroxy-naphthalene is assumed.

Synthetic route B

The introduction of the rest of the invention in the In dolin part usually takes place before the actual one Indole synthesis.

Which may seem easier at first glance method of per-alkylation of the commercially available 5-hydroxyindoles and etherification of the free hydroxy group with the residues according to the invention results only very much poor yields.

The use of ether gives better results phenylamines and their implementation.

In all cases, the indoline base is in the form of its Indolenium salt (methyl iodide) used, since most of the time existing ester functions under the conditions of Formation of the free methylene base using strong alkali be hydrolyzed.

The following example is intended only as an example demonstrate:  

93 g of commercially available phenoxyphenylamine is dissolved in 1 liter of toluene dissolved and dry HCl gas passed through. The first The precipitate is filtered off and white with acetone washed. 74 g (0.3 mol) of this hydrochloride with 62 g (0.3 mol) phenoxyphenylamine and (0.3 mol) 29.5 g (0.3 mol) acetoin finely ground, to melt brought and stirred for 30 minutes in an oil bath (140 ° C). The hot melt is in a large glass or porcelain shell tilted and allowed to solidify.

After crushing, it is pulverized and 2 h in 3 l Stirred 12% hydrochloric acid. The precipitate sucked off is washed with 2% HCl, dried and in warm Dissolved ethanol (60 ° C). Fall in the freezer overnight (-28 ° C) crystals. These are sucked off, that The filtrate was concentrated to 1/4. Thereby more crystals fall out. The combined yellow to ocher Crystal masses are recrystallized twice from ethanol. The NMR analysis of the white, silvery needles shows the product as 2,3-dimethyl-5-phenoxy-indole.

45 g of this compound are mixed in 100 ml of ethanol with 45 g of methyl iodide, reacted for 4 h in an autoclave at 105 ° C. After cooling overnight, the solvent and excess alkylating agent are removed from the mixture on the Rotavap. The dark oil is poured into 80 ml KOH (31 g KOH to 80 ml H ₂ O), warmed to 75 ° C, stirred for 30 min, allowed to cool and extracted with ether. After drying with Na ₂ SO ₄ and filtering, the ether is removed from the filtrate. The fractional HV distillation gives several fractions, of which the middle ones, the 1,3,3-dimethyl-2-methylene-5-phenoxy-indole and 1,3,3-trimethyl-2-methylene-5-phenoxy-indole and Contain 2,3,3-trimethyl-5-phenoxy-indolenine.

66 g of this mixture (from 2 batches) are dissolved in as little DMF as possible with 50 g of methyl iodide and boiled on a water bath for 45 min. After the removal of the solvent and alkylating agent, the remaining tarry black mass is extracted with toluene in the extractor. The remaining gray-brown crystal mass is recrystallized from ethanol / water. The NMR analysis of the salt shows:
1,1,3,3-tetramethyl-2-methylene-5-phenoxy-indolenium (iodide).

The non-commercially available etherphenylamines are made Aminophenols and alkyl bromide (after acetylation of the Amino function) obtained analogously to synthesis route A2.

The conversion to photochromic also takes place Spiroindolino-naphthoxazine analogous to A5, but because of the use of the indolenium salt is at least equimolar Amounts of condensing agent are required.

Of course, Ver bonds are generated, both in the indoline, as in Naphthoxazinteil corresponding ethers and / or Bear ester functions by in the aforementioned reaction analogous to A5, the nitroso products obtained in A4 be set.  

Table 1

Surfaces according to known methods (DE 35 16 568 A1) colored zero glasses made of diethylene glycol bisallyl car bonat were subjected to normal cleaning and then in a high vacuum with a multiple layer for anti-reflective coating (DE 43 11 572 A1).

The glasses were left at room temperature for 42 hours and then a boiling test in 4% NaCl solution throw. The test was carried out for 2 minutes Glasses checked for layer detachments. The test was until the beginning of layer separation, but at most Repeated 12 times. The substances according to the invention showed significantly better behavior, which indicates the ver reduced migration of the photochromic dyes to the Surface can be traced, which leads to the detachment of the evaporated anti-reflective layers leads.  

Table 2

Beginning of layer detachment in the xth test cycle: 20 glasses per test series

They are striking compared to the almost simultaneously  experiments with photochromic pyrans P 44 17 894.8 better results of those examined here Oxazine.

Claims (1)

1. Spirooxazine compounds with the general structure
mean here

• 1. R ₁ , R ₂ , R ₃ and R ₄ independently of one another: H, halogen, G, OG, NG ₂ or OT,
• 2. R ₅ , R ₆ and R ₇ independently of one another: G,
• 3. R ₈ : H, NG ₂ or 1-piperidyl and
• 4. R ₉ , R ₁₀ independently of one another: H, halogen, G, OG or OT,

in which

• 1. G is a C ₁ -C ₆ alkyl, C ₅ -C ₇ cycloalkyl, phenyl, naphthyl or benzyl group,
• 2. at least one of the substituents R ₁ to R ₄ , R ₉ or R _{10 is} one of the groups -O-phenyl, -O-benzyl or -OT and
• 3. T either an adamantane, camphor, norbornane [2.2.1] -, pinane [3.3.1] -, norcarane [4.1.0] -, tricyclene, 1-azabi cyclo [2.2.2] octane or 3 -Azabicyclo [3.2.2.] Nonane radical or one of the following groupings:
  - (CH ₂ ) _n -O- (CH ₂ ) _m -CH ₃ , - (CH ₂ ) _n -O- (CH ₂ ) _n -O- (CH ₂ ) _m -CH ₃ ,
  with n = 1, 2, 3, 4 and m = 0, 1, 2, 3.