DE10234326B3 - Novel acrylic ester phosphonic acids for use in dental materials e.g. cements or adhesives comprise improved hydrolytic stability - Google Patents

Abstract

Acrylic ester phosphonic acids and their stereoisomers and mixtures are new. Novel acrylic ester phosphonic acids are of formula (I), their stereoisomers and mixtures also being new. R1 when n=1 = group of formula (A) or (B); R1 when n=2 = group of formula (C)-(E); R2 = 1-12C alkylene, 4-8C cycloalkylene or 7-15C alkylenephenylene; R3 = H, 1-5C alkyl or 1-5C O-alkyl; and R4 and R5 = 1-5C alkyl or 1-5C O-alkyl. An Independent claim is also included for compositions containing (I).

Description

The present invention relates to Acrylesterphosphonsäuren, which has high hydrolysis stability have and in particular for the production of dental materials suitable.

Polymerizable phosphonic acids are especially as comonomers of polymer-chemical importance and allow the production of organic, high thermal polymers Stability, good adhesive properties, low flammability and good solubility in polar solvents. For this The purpose is numerous monomeric phosphonic acids with polymerizable vinyl, Dienyl, allyl or styryl groups are synthesized and polymerized Service. An overview to phosphonic acids gives Houben-Weyl, Methods of Organic Chemistry, Volume E 20 (2nd Part), G. Thieme Verlag, Stuttgart-New York 1987, 1300 ff. Examples of such conventional polymerizable phosphonic acids are vinylphosphonic acid, allylbenzenephosphonic acid, α-aminoallylphoshonic acid, 1,3-butadiene or isoprene phosphonic acid, 4-vinylbenzenephosphonic acid or 2- (4-vinylphenyl) ethanephosphonic acid.

Phosphonic acids where the C = C grouping directly or via an oxygen atom is attached to the phosphorus atom, e.g. in vinylphosphonic or ethylphosphonic acid monovinyl ester, have only a slight tendency to homopolymerize, so that only homopolymers can be obtained with a low molecular weight.

From the DE 199 18 974 A1 are dental materials based on polymerizable (meth) acrylic acid derivatives of phosphonic acids, such as 2-methacryloyloxyethylphosphonic acid, in which the polymerizable (meth) acrylic group is bonded to the phosphorus via an alkylene radical. These compounds can be polymerized well, but are not stable to hydrolysis.

The DE 197 46 708 A1 discloses polymerizable acrylic phosphonic acids which are stable to hydrolysis in aqueous solution, have good adhesive properties, can be polymerized with conventional radical initiators and are therefore particularly suitable as a constituent of dental materials. In the form of their carboxylic acid esters, the acrylic phosphonic acids show good solubility in water and polar organic solvents, while in the form of the carboxylic acids they are readily soluble in water but hardly soluble in organic solvents. The different solution behavior of ester and acid can be disadvantageous for water-containing materials. Hydrolysis of the carboxylic acid esters to free carboxylic acid with the elimination of alcohol can significantly change the solubility of the monomers and thus lead to partial or complete precipitation of the phosphonic acid component and thus influence the properties of the material.

The DE 100 18 968 discloses dental materials based on hydrolysis-stable acrylamide and acrylonitrilephosphonic acids.

AT THE. Kawamoto, M.M. Campbell, J. Chem. Soc., Perkin Trans. 1, 1997, 1249 describe difluorovinylphosphonate analogs of phosphoenolpyruvate, the potential inhibitors of the shikimic acid pathway should represent.

Finally, are out of EP 1 169 996 A1 Phosphonic acid derivatives are known in which polymerizable groups are bonded to a phosphonic acid group via an amide group, such as in 4-methacrylamido-4-methylpentylphosphonic acid. These compounds have only a low radical polymerizability.

The invention is based on the object polymerizable acrylophosphonic to provide the opposite known acrylic phosphonic acids characterized by a further improved resistance to hydrolysis.

in der
n 1 oder 2 ist,
mit der Maßgabe, daß
für n = 1 R¹ die Bedeutung

und für n = 2 R¹ die Bedeutung

hat;
R² ein C₁ bis C₁₂-Alkylenrest, C₄-C₈-Cycloalkylenrest oder C₇- bis C₁₅-Alkylenphenylenrest ist;
R³ Wasserstoff , ein C₁- bis C₅-Alkylrest oder ein C₁- bis C₅-O-Alkylrest ist; und
R⁴, R⁵ unabhängig voneinander jeweils für einen C₁- bis C₅-Alkylrest oder einen C₁- bis C₅-O-Alkylrest stehen.According to the invention, this object is achieved by acrylic ester phosphonic acids of the general formula (I), stereoisomers thereof and mixtures of these,

in the
n is 1 or 2,
with the proviso that
the meaning for n = 1 R ¹

and for n = 2 R ¹ the meaning

Has;
R ^{2 is} a C ₁ to C ₁₂ alkylene radical, C ₄ -C ₈ cycloalkylene radical or C ₇ to C ₁₅ alkylene phenylene radical;
R ^{3 is} hydrogen, a C ₁ to C ₅ alkyl radical or a C ₁ to C ₅ O-alkyl radical; and
R ⁴ , R ⁵ each independently represent a C ₁ - to C ₅ -alkyl radical or a C ₁ - to C ₅ -O-alkyl radical.

The individual alkyl and alkylene residues can be straight-chain, branched or cyclic.

The individual radicals R2, R3, R4 and / or R5 can be unsubstituted or by one or more substituents, such as Cl, Br, CH ₃ O, OH, COOH, CN, = O, = S, = NR ⁶ or -NR ⁷ - CO-C (= CH ₂ ) CH ₂ -YR ⁸ -PO (OH) ₂ , preferably Cl, CH ₃ O, OH, COOH, = O or = NR ⁶ , where R ⁶ and R ⁷ are each independently Are hydrogen, a straight-chain or branched C ₁ - to C ₁₀ -alkyl or C ₆ - to C ₁₀ -aryl radical, preferably hydrogen or a straight-chain C ₁ - to C ₃ -alkyl radical and R ^{8 is} a straight-chain or branched C ₁ - to C ₁₀ alkylene or C ₆ to C ₁₄ arylene radical, preferably a straight-chain or branched C ₁ to C ₅ alkylene radical or phenylene.

The invention further relates to the Use of these hydrolysis-stable acrylic ester phosphonic acids for the preparation of polymers, adhesives, Dental materials or other materials and materials. object of the present invention are also the use of acrylic ester phosphonic acids as Component of adhesives, Cements, composites, moldings or dental materials as well as polymers or copolymers, which by Homo- or copolymerization of the acrylic ester phosphonic acids are available.

R² = ein C₁ bis C₆-Alkylenrest;
R³ = Wasserstoff, ein C₁- bis C₃-Alkylrest; und
R⁴, R⁵ = unabhängig voneinander jeweils ein C₁- bis C₃-Alkylrest.The following preferred definitions exist for the variables of the formula (I) given above, which, unless stated otherwise, can be selected independently of one another:
n = 1,
R ¹ =

R ² = a C ₁ to C ₆ alkylene radical;
R ³ = hydrogen, a C ₁ to C ₃ alkyl radical; and
R ⁴ , R ⁵ = each independently a C ₁ - to C ₃ -alkyl radical.

Preferred compounds are accordingly those in which at least one of the variables of formula (I) the above described preferred definition. Particularly preferred monomers according to the invention are those in which all variables are one of the preferred meanings to have.

The acrylic ester phosphonic acids of the formula (I) according to the invention can be obtained by esterification of corresponding OH group-containing mono- (n = 1) or difunctional (n = 2) compounds R ¹ - (OH) _n with suitable COOH group-containing acrylate ether phosphonic acid esters AEPE analogously to the methods known in the literature for the preparation of carboxylic acid esters (cf., inter alia, B. Neises, W. Steglich, Angew. Chem. 90 (1978) 556, or A. Hassner, V. Alexanian, Tetrahedron Lett. 46 (1978) 4475) in the presence of dicyclohexylcarbodiimide (DCC) and 4-dimethylaminopyridine (DMAP), hydrolytic cleavage of the protective groups (SG) by silylation with trialkylsilanes, e.g. trimethylsilyl chloride / NaI or bromide (TMSBr), and subsequent reaction with alcohols, such as methanol, or water (S Freeman, J. Chem. Soc., Perkin Trans. 2 (1991) 263.).

Generally:

Concrete example:

The suitable ones can contain COOH groups Acrylatetherphosphonsäureester AEPE from the corresponding carboxylic acid esters by partial hydrolysis, e.g. with an equimolar Analogue amount of lye at -5 ° C on literature (see N. Moszner, F. Zeuner, U. K. Fischer, V. Rheinberger, Macromol. Chem. Phys. 200 (1999) 1062).

Preferred examples of the acrylic esterphosphonic acids of the formula (I) are:

The acrylic ester phosphonic acids according to the invention are strongly acidic and very good in water or mi water with polar solvents such as acetone, ethanol, acetonitrile or tetrahydrofuran (THF) soluble. In them, the acidic phosphonic acid group is connected to the polymerizable acrylate group via a hydrolysis-stable ether group. In addition, the ester group in the acrylic esterphosphonic acids according to the invention also has high hydrolysis stability, which, taken together, represents a significant improvement over conventional polymerizable acrylicphosphonic acids.

In connection with the present According to the invention, such compounds are termed hydrolysis-stable, those in water or in mixtures of water and water-miscible solvents at a concentration of approx. 20% by weight and a pH of 2.0 at 37 ° C for are stable for at least 6 weeks, i.e. hydrolyze to less than 1%.

Due to the presence of polymerizable The acrylic phosphonic acid esters according to the invention are suitable for groups as starting materials for the production of polymers and copolymers. In doing so, they leave with the known methods of radical polymerization homopolymerize or e.g. copolymerize with suitable comonomers.

The acrylic ester phosphonic acids according to the invention can in free form or in the form of their salts, i.e. as phosphonates or Phosphonate esters are used, being in the case of the salts as Counterions preferably alkali metal ions, especially sodium and lithium ions, as well as organic ammonium ions, in particular those which amine accelerators, such as N, N-dihydroxyethyl-p-toluidine, N, N-bis (2-hydroxy-3-methacryloxypropyl-3,5-xylidine or 4- (dimethylamino) benzoic acid 2-ethylhexyl ester. Amine accelerators are used as a component in the dental field, for example used by photoinitiator systems. It is generally by tert. Amines that can act as H donors and thus radical formation accelerate (see L.A. Linden, "Photocuring of Polymeric Dental Materials and Plastic Composite Resins "in Radiation Curing in Polymer Science and Technology, Vol. IV, J.P. Fouassier, J.F. Rabek (Editor), Elsevier Appl. Sci., London, New York 1993, 396f.).

To carry out the polymerization, the known radical initiators (cf. Encyclopedia of Polymer Science and Engineering, Vol. 13, Wiley-Interscience Publisher, New York 1988, 754 ff.) Are used.

To initiate the radical Photopolymerization are preferably benzophenone, benzoin as well their derivatives or α-diketones or their Derivatives such as 9,10-phenanthrenequinone, 1-phenyl-propane-1, 2-dione, or diacetyl 4,4-dichlorobenzil used. Camphorquinone and 2,2-methoxy-2-phenyl-acetophenone and particularly preferably α-diketones in combination with amines as reducing agents, e.g. 4- (dimethylamino) benzoic acid ester, N, N-dimethylaminoethyl methacrylate, N, N-dimethyl-sym.-xylidine or Triethanolamine.

Suitable as thermal initiators especially azo compounds such as azo bis (isobutyronitrile) (AIBN) or Azobis (4-cyano-valeric acid) or peroxides, such as dibenzoyl peroxide, dilauroyl peroxide, tert-butyl peroctoate, tert-butyl perbenzoate or di (tert-butyl) peroxide. Benzpinacol are also suitable as initiators for hot curing and 2,2'-dialkylbenzpinacoles. As initiators for one carried out at room temperature Polymerization are redox initiator combinations, such as. Combinations of benzoyl peroxide with N, N-dimethylsym.-xylidine or N, N-dimethyl-p-toluidine, used. About that there are also redox systems consisting of peroxides and such Reducing agents, e.g. Ascorbic acid, barbiturates or sulfinic acids, especially suitable.

The invention also provides Compositions containing one or more acrylic ester phosphonic acids according to formula (I) and also also an initiator for which contain radical polymerization.

Due to the hydrolysis stability of the acrylic ester phosphonic acids according to the invention the compositions at room temperature even in the presence of water storage stable and are particularly suitable as adhesives or cements for dental Applications.

Compositions are further preferred, which in addition to acrylic ester phosphonic acid and initiator if necessary contain one or more radically polymerizable monomers.

Monofunctional ones are suitable as comonomers and / or polyfunctional free-radically polymerizable monomers, especially difunctional crosslinking monomers. Among monofunctional Monomers become compounds with one, among multifunctional ones Monomeric compounds with two and more radical polymerizable Understood groups. For the. Manufacture of adhesives or dental materials are particularly suitable for crosslinking bi- or multifunctional acrylates or methacrylates, e.g. Bisphenol A di (meth) acrylate, Bis-GMA (the addition product of methacrylic acid and bisphenol A diglycidyl ether), UDMA (the addition product of hydroxyethyl methacrylate and 2,2,4-trimethylhexamethylene diisocyanate), Di-, tri- or tetraethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate and pentaerythritol tetra (meth) acrylate. The are also suitable by esterification of (meth) acrylic acid with the corresponding diols accessible Compounds butanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate and 1,12-dodecanediol di (meth) acrylate.

Particularly preferred radical polymerizable monomers are acrylamides or hydroxyalkylacrylamides.

steht, die über das Stickstoffatom oder über C-2 an den Rest B gebunden ist, wobei die nicht mit B verbundene Bindungsstelle einen Rest R^2' trägt,
R^1' Wasserstoff, eine Alkylgruppe mit 1 bis 20 Kohlenstoffatomen oder ein Phenylrest ist, wobei sich zwei oder mehr Reste X' einen Rest R^1' teilen können und wobei R^1' auch Bestandteil des Restes B sein kann,
R^2' Wasserstoff, eine Alkylgruppe mit 1 bis 20 Kohlenstoffatomen oder ein Phenylrest ist, und
n' eine Zahl von 2 bis 5 ist.Because of their hydrolysis stability, amides of the general formula BX _{n are} particularly preferred in which
B represents an n-fold hydrocarbon radical having 1 to 50 carbon atoms which is substituted by the group x 'and which has one or more of the groups O, S, NH, CO-NH, NH-CO, NH-CO-O, O-CO- May contain NH and / or NH-CO-NH,
X 'for the group

which is bonded to the radical B via the nitrogen atom or via C-2, the binding site not connected to B carrying a radical R ^{2 '} ,
R ^{1 'is} hydrogen, an alkyl group with 1 to 20 carbon atoms or a phenyl radical, where two or more radicals X' can share a radical R ^{1 '} and where R ^{1' can} also be part of the radical B,
R ^{2 'is} hydrogen, an alkyl group having 1 to 20 carbon atoms or a phenyl radical, and
n 'is a number from 2 to 5.

The group X 'is N-substituted Amide groups that over the amide nitrogen or over the carbon atom C-2 is bonded to the radicals B.

Amides of this type, preferred derivatives thereof and their preparation are described in the DE 101 01 523 disclosed.

in der
X" für einen C₁- bis C₁₂-Alkylenrest oder C₇- bis C₁₅-Alkylenphenylenrest, vorzugsweise für einen C₁- bis C₁₀-Alkylenrest und ganz besonders bevorzugt für einen C₁- bis C₈-Alkylenrest steht,
R^{1 "} für einen C₁- bis C₁₀-Alkylrest, Phenyl oder Wasserstoff steht, vorzugsweise für einen C₁- bis C₆-Alkylrest oder Wasserstoff, besonders bevorzugt einen C₁- bis C₃-Alkylrest oder Wasserstoff steht,
m", n" unabhängig voneinander 0, 1 oder 2 sind, wobei m" + n" gleich 2 ist, und
R^{2 "} für Wasserstoff, Methyl oder X'''-OH steht, wenn m" größer oder gleich 1 ist, oder für X'''-OH steht, wenn m" gleich 0 ist, wobei X''' eine der für x" angegebenen Bedeutungen hat und vorzugsweise C₁- bis C₆-Alkylen, besonders bevorzugt C₁- bis C₃-Alkylen ist, und wobei für n" = 2 die beiden Reste R^1" und für m" = 2 die beiden Reste -X"- gleich oder verschieden sein können. Die obigen Hydroxyalkylacrylamide enthalten keine Aldehydgruppen.Hydroxyalkylacrylamides of the formula are further preferred

in the
X "represents a C ₁ to C ₁₂ alkylene radical or C ₇ to C ₁₅ alkylene phenylene radical, preferably a C ₁ to C ₁₀ alkylene radical and very particularly preferably a C ₁ to C ₈ alkylene radical,
R ^{1 "represents} a C ₁ to C ₁₀ alkyl radical, phenyl or hydrogen, preferably a C ₁ to C ₆ alkyl radical or hydrogen, particularly preferably a C ₁ to C ₃ alkyl radical or hydrogen,
m ", n" are independently 0, 1 or 2, where m "+ n" is 2, and
R ^{2 "stands} for hydrogen, methyl or X '''- OH if m" is greater than or equal to 1, or stands for X''' - OH if m "is 0, where X '''is one of x "has the meanings indicated and is preferably C ₁ - to C ₆ -alkylene, particularly preferably C ₁ - to C ₃ -alkylene, and wherein for n" = 2 the two radicals R ^{1 "} and for m" = 2 the two radicals -X "- may be the same or different. The above hydroxyalkylacrylamides contain no aldehyde groups.

For the alkyl and alkylene radicals mentioned it is preferably linear groups. Connections, at those m "and n" each equal 1 are particularly preferred. Further preferred are compounds which have 1, 2 or 3 hydroxyl groups per molecule.

Hydroxyalkylamides of this type, preferred derivatives thereof and their preparation are in the DE 102 28 540 described.

Preferred monofunctional radical polymerizable monomers that are particularly useful as diluent monomers are hydrolysis-stable mono (meth) acrylates, e.g. mesityl, or 2- (alkoxymethyl) acrylic acids, such as. 2- (ethoxymethyl) acrylic acid, 2- (hydroxymethyl) acrylic acid, N-mono- or disubstituted Acrylamides, e.g. N-ethyl, N, N-dimethacrylamide, N- (2-hydroxyethyl) acrylamide or N- (2-hydroxyethyl) -N-methyl-acrylamide, as well as N-monosubstituted Methacrylamides, e.g. N-ethyl methacrylamide or N- (2-hydroxyethyl) methacrylamide and also N-vinylpyrrolidone or allyl ether.

Preferred multifunctional radical polymerizable monomers, which are particularly suitable as crosslinking monomers are hydrolysis-stable urethanes from 2- (hydroxymethyl) acrylic acid and Diisocyanates, e.g. 2,2,4-trimethylhexamethylene diisocyanate or Isophorone diisocyanate, cross-linking pyrrolidones, e.g. 1,6-bis (3-vinyl-2-pyrrolidonyl) -hexane, or commercially available Bisacrylamides such as methylene or ethylene bisacrylamide, or bis (meth) acrylamides, such as. N, N'-diethyl-1,3-bis (acrylamido) propane, 1,3-bis (methacrylamido) propane, 1,4-bis (acrylamido) butane or 1,4-bis (acryloyl) piperazine, by reaction from the corresponding diamines with (meth) acrylic acid chloride can be synthesized.

The compositions may contain one or more of the comonomers mentioned. Before compositions are added which contain at least one multifunctional free-radically polymerizable monomer.

Furthermore, the compositions according to the invention can be filled with organic or inorganic particles to improve the mechanical properties or to adjust the viscosity. Preferred inorganic particulate fillers are amorphous spherical materials based on oxides, such as ZrO ₂ and TiO ₂ or mixed oxides composed of SiO ₂ , ZrO ₂ and / or TiO ₂ , nanoparticulate or microfine fillers, such as pyrogenic silica or precipitated silica, and mini-fillers, such as quartz -, glass ceramic or glass powder with an average particle size of 0.01 to 1 μm and X-ray opaque fillers, such as ytterbium trifluoride or nanoparticulate tantalum (V) oxide or barium sulfate.

The compositions according to the invention can furthermore contain free-radically polymerizable phosphoric acid derivatives. Hydrolysis-stable phosphoric acid derivatives, such as (meth) acrylamidoalkyl dihydrogen phosphates, in particular 6- (N-methacryloylamino) hexyl and 2- (N-methacryloylamino) ethyl dihydrogen phosphate, are preferred. These compounds improve the etching effect of the composition and are therefore particularly suitable for producing self-etching dental materials, such as adhesives and cements. Alkyl here stands for C ₁ to C ₁₂ alkyl, preferably for C ₁ to C ₆ alkyl.

The compositions according to the invention also contain preferably also a solvent, such as esters, e.g. Ethyl acetate, preferably water, ethanol, acetone, Methylene chloride, acetonitrile or mixtures thereof. Are preferred Compositions used as solvents Water or a mixture of solvents containing water contain.

In addition, the compositions of the invention contain further additives, e.g. Stabilizers, flavorings, microbiocides Active ingredients, fluoride ion releasing additives, optical brighteners, Plasticizer and / or UV absorber.

Compositions that are exclusively stable to hydrolysis Contain components according to the definition above a very particularly preferred embodiment of the invention.

The compositions according to the invention are suitable are particularly suitable for the production of dental materials, such as cements, for example of self-adhesive fastening cements, and in particular of adhesives. Such adhesives are characterized by very good adhesion to the tooth structure and are stable to hydrolysis under moist conditions.

• a) 0,5 bis 70 Gew.-%, bevorzugt 10 bis 60 Gew.-% und besonders bevorzugt 15 bis 50 Gew.-% Acrylesterphosphonsäure gemäß Formel (2),
• b) 0,01 bis 15 Gew.-%, besonders bevorzugt 0,1 bis 8,0 Gew.-% Initiator für die radikalische Polymerisation,
• c) 0 bis 80 Gew.-%, bevorzugt 0 bis 60 Gew.-% und besonders bevorzugt 10 bis 50 Gew.-% radikalisch polymerisierbares Monomer,
• d) 0 bis 95 Gew.-%, bevorzugt 0 bis 80 Gew.-%, besonders bevorzugt 10 bis 70 Gew.-% und ganz besonders bevorzugt 20 bis 60 Gew.-% Lösungsmittel,
• e) 0 bis 50 Gew.-%, bevorzugt 0 bis 30 Gew.-%, besonders bevorzugt 0 bis 20 Gew.-% und ganz besonders bevorzugt 10 bis 20 Gew.-% (Meth)acrylamidoalkyl-dihydrogenphosphat,
• f) 0 bis 75 Gew.-%, besonders bevorzugt – in Abhängigkeit von der Anwendung – 0 bis 20 Gew.-% (Adhäsiv) oder 20 bis 75 Gew.-% (Zement) Füllstoff.

Preferred dental materials contain the following components (a), (b), (c), (d), (e) and / or (f):

• a) 0.5 to 70% by weight, preferably 10 to 60% by weight and particularly preferably 15 to 50% by weight of acrylic ester phosphonic acid according to formula (2),
• b) 0.01 to 15% by weight, particularly preferably 0.1 to 8.0% by weight, of initiator for the radical polymerization,
• c) 0 to 80% by weight, preferably 0 to 60% by weight and particularly preferably 10 to 50% by weight of radically polymerizable monomer,
• d) 0 to 95% by weight, preferably 0 to 80% by weight, particularly preferably 10 to 70% by weight and very particularly preferably 20 to 60% by weight of solvent,
• e) 0 to 50% by weight, preferably 0 to 30% by weight, particularly preferably 0 to 20% by weight and very particularly preferably 10 to 20% by weight of (meth) acrylamidoalkyl dihydrogen phosphate,
• f) 0 to 75% by weight, particularly preferably - depending on the application - 0 to 20% by weight (adhesive) or 20 to 75% by weight (cement) filler.

Compositions are particularly preferred, which contain at least components (a), (c) and (d).

The invention is illustrated below of examples closer explained.

Examples

example 1

Synthesis of 2,4,6-trimethylphenyl 2- [2-dihydroxyphosphoryl) ethoxymethyl] acrylic acid (MAPA)

1st stage

2- [2-dimethoxyphosphoryl) -ethoxymethyl] -acrylic acid-2,4,6-trimethyl-phenyl ester (MAPAME)

To a solution of 27.6 g (116 mmol) of 2- [4- (dimethoxyphosphoryl) -2-oxabutyl] acrylic acid, which according to literature (N. Moszner, F. Zeuner, S. Pfeiffer, 2. Schurte, V. Rheinberger, M. Drache, Macromol. Mater. Eng. 286 (2001) 225) by partial hydrolysis of ethyl 2- [4- (dimethoxyphosphoryl) -2-oxabutyl] acrylic acid, 1.33 g (11 mmol) 4- Dimethylaminopyridine and 15.0 g (116 mmol) of mesitol in 60 ml of THF were added in portions to 24.5 g (128 mmol) of N- (3-dimethylaminopropyl) -N-ethylcarbodiimide hydrochloride within 3 h added with vigorous stirring. The mixture was allowed to react further at room temperature overnight. The volatile constituents were then stripped off and the remaining oily residue was taken up in 250 ml of methylene chloride. The mixture was shaken with 0.5N hydrochloric acid, washed neutral and dried over anhydrous sodium sulfate. Finally, all volatile constituents were removed in a fine vacuum and the crude product was purified by column chromatography: silica gel column, mobile phase THF / toluene 1: 1. 11.9 g of MAPAME (29% yield) are obtained as a colorless oil.
¹ H NMR (400 MHz, CDCl ₃ , ppm): 2.10 (s, 6H, o-CH ₃ ), 2.17 (dt, 2H, PCH ₂ ), 2.27 (s, 3H, p-CH ₃ ), 3.75 (d, 6H, = CH ₃ ), 3.81 (m, 2H, PCH ₂ C H ₂ ), 4.34s, 2H, OCH ₂ C =), 6.07 and 6.56 ( 2s, 1H, = CH ₂ ) and 6.87 (S, 2H, C _ar H).
¹³ C-NMR (CDCl ₃ , 100 MHz): 16.1 (OC _ar . C _ar . C H ₃ ), 20.8 (OC _ar . C _ar . C _ar . C _ar. C H ₃ ), 24.8 (d, P C H ₂ CH ₂ , ¹ J _{C, P} = 140.2 Hz), 52.3 (d, OCH ₃ , ² J _{C, P} = 6.5 Hz), 64.7 (PCH ₂ C H ₂ ), 69.2 (O C H ₂ C =) , 127.4 (C = C H ₂ ), 129.2 (C _{ar .} H), 129.7 (OC _{ar .} C _{ar .} CH ₃ ), 135.4 (OC _ar . C _ar . C _ar . C _ar CH ₃ ), 136.4 ( C = CH ₂ ), 145.7 (OC _{ar .} ), 163.7 (C = O).
³¹ P NMR (CDCl ₃ , 162 MHz): = + 32.5.

2nd stage

2- [2-dihydroxyphosphoryl) -ethoxymethyl] -acrylic acid-2,4,6-trimethyl-phenyl ester

To a mixture of 9.83 g (27.6 mmol) of the compound MAPAME and 2.7 mg of phenothiazine MEHQ 10.56 g (69 mmol) trimethylsilyl bromide was carefully added dropwise under argon and 3 h at 45 ° C touched. Then the mixture was concentrated on a rotary evaporator with 60 ml of methanol offset, about Stirred at night, concentrated in a fine vacuum and dried to constant weight. There remained 8.77 g (97% yield) of a very viscous oil from MAPA.

¹ H-NMR (CDCl ₃ , 400 MHz): = 2.08 (s, 6H, O-CH ₃ ), 2.18 (dt, 2H, PCH ₂ ), 2.26 (s, 3H, p-CH ₃ ), 3.82 (m , 2H, PCH ₂ C H ₂ ), 4.31 (s, 2H, OCH ₂ C =), 6.06, 6.55 (each S, 1H, = CH ₂ ), 6.86 (s, 2H, C _{ar .} H), 9.48 ( br, 2H, POH).

¹³ C-NMR (CDCl ₃ , 100 MHz): = 16.2 (OC _ar . C _ar . C H ₃ ), 20.8 (OC _ar . C _ar . C _ar . C _ar . C H ₃ ), 26.8 (d, P C H ₂ CH ₂ , ⁱ J _{C, P} = 143.6 Hz), 64.6 (PCH ₂ C H ₂ ), 69.2 (O C H ₂ C =), 127.9 (C = C H ₂ ), 129.2 (C _ar. H ), 129.7 (OC _ar. C _ar. CH ₃ ), 135.4 (OC _ar . C _ar . C _ar . C _ar . CH ₃ ), 136.1 (C = CH ₂ ), 145.7 (OC _ar .), 163.8 (C = O).

³¹ P NMR CDCl ₃ , 162 MHz): = + 33.6.

Example 2

Investigation of the hydrolysis stability of MAPA

A 20% solution of MAPA, stabilized with 200 ppm 2,6-di-t-butyl-4-methylphenol, was prepared in D ₂ O / EtOH-d ₆ (1: 1) and stored at 37 ° C. and ¹ H-NMR spectroscopy. After a standing time of 2 months, no changes in the ¹ H-NMR spectrum were found.

Example 3

Manufacture chemically curing adhesive based on MAPA

For examining the dentin adhesion cattle dentists were given adhesives with the following composition (data in% by weight):

Table 1 Composition and adhesion values for dental adhesives based on MAPA

Bovine teeth were embedded in plastic cylinders so that the dentin and the plastic were in one plane. With a small brush, one layer of the above adhesive was massaged into the dentin surface for 15 s and slightly blown with an air blower. A prepolymerized cylinder made of dental composite material (Tetric ^® Ceram, Ivoclar Vivadent AG) and coated with a self-curing cement was applied to the adhesive layer and cured in the dark for 10 minutes. The test specimens were then stored in water for 24 hours at 37 ° C. and the shear bond strength was determined in accordance with the ISO guideline “ISO 1994-ISO TR 11405: Dental Materials Guidance on Testing of Adhesion to Tooth Structure”. The results are summarized in Table 1. They show that the acrylic ester phosphonic acids according to the invention are not only stable to hydrolysis but also ensure high adhesion between dentin and composite material.

Claims (17)

Acrylic ester phosphonic acid of the general formula (2), stereoisomers thereof and mixtures thereof,

in which n is 1 or 2, with the proviso that for n = 1 R ¹ the meaning

and for n = 2 R ¹ the meaning

Has; R ^{2 is} a C ₁ to C ₁₂ alkylene radical, C ₄ -C ₈ cycloalkylene radical or C ₇ to C ₁₅ alkylene phenylene radical; R ^{3 is} hydrogen, a C ₁ to C ₅ alkyl radical or a C ₁ to C ₅ O-alkyl radical; and R ⁴ , R ⁵ each independently represent a C ₁ - to C ₅ -alkyl radical or a C ₁ - to C ₅ -O-alkyl radical. Acrylic ester phosphonic acid according to Claim 1, characterized in that one or more of the variables of the formula (2) independently of one another have the following meaning: n = 1, R ¹ =

R ² = a C ₁ to C ₆ alkylene radical; R ³ = hydrogen, a C ₁ to C ₃ alkyl radical; and R ⁴ , R ⁵ = independently of one another a C ₁ to C ₃ alkyl radical. Acrylic ester phosphonic acid according to claim 1 or 2, characterized in that the radicals R ² , R ³ , R ⁴ and / or R ^{5 are} unsubstituted or selected by one or more substituents from the group Cl, Br, CH ₃ O, OH, COOH, CN , = O, = S, = NR ⁶ or -NR ⁷ -CO-C (= CH ₂ ) CH ₂ -YR ⁸ -PO (OH) ₂ are substituted, wherein R ⁶ and R ⁷ each independently represent hydrogen, a straight-chain or branched C ₁ - to C ₁₀ -alkyl or C ₆ - to C ₁₀ -aryl radical and R ^{8 is} a straight-chain or branched C ₁ - to C ₁₀ -alkylene or C ₆ - to C ₁₄ -arylene radical. Composition, characterized in that it follows an acrylic ester phosphonic acid one of the claims Contains 1 to 3. Composition according to Claim 4, characterized in that it additionally comprises a contains radically polymerizable monomer. Composition according to Claim 5, characterized in that it is used as radical polymerizable monomer an acrylamide and / or Contains hydroxyalkylacrylamide. Composition according to claim 5 or 6, characterized in that she a monofunctional and / or a multifunctional radical contains polymerizable monomer. Composition according to Claim 7, characterized in that it is a monofunctional radical cally polymerizable monomer One or more hydrolysis-stable mono (meth) acrylates, mesityl methacrylate, one or more 2- (alkoxymethyl) acrylic acids, 2- (ethoxymethyl) acrylic acid, 2- (hydroxymethyl) acrylic acid, one or more N-mono- or N-disubstituted Acrylamides, N-ethyl acrylamide, N, N-dimethacrylamide, N- (2-hydroxyethyl) acrylamide, N- (2-hydroxyethyl) -N-methyl-acrylamide, one or more N-monosubstituted methacrylamides, N-ethyl methacrylamide, N- ( Contains 2-hydroxyethyl) methacrylamide, N-vinylpyrrolidone, allyl ether or a mixture of two or more of these monomers. Composition according to claim 7 or 8, characterized in that she as a multifunctional free-radically polymerizable monomer or more urethanes from 2- (hydroxymethyl) acrylic acid and Diisocyanates, 2,2,4-trimethylhexamethylene diisocyanate, Isophorone diisocyanate, one or more crosslinking pyrrolidones, 1,6-bis (3-vinyl-2-pyrrolidonyl) hexane, one or more bisacrylamides, methylene bisacrylamide, ethylene bisacrylamide, one or more bis (meth) acrylamides, N, N'-diethyl-1,3-bis (acrylamido) propane, 1,3-bis (methacrylamido) propane, 1,4-bis (acrylamido) butane, 1,4-bis (acryloyl) piperazine or one Mixture of two or more of these monomers contains. Composition according to one of Claims 4 to 9, characterized in that that she additionally an initiator for which contains radical polymerization. Composition according to one of Claims 4 to 10, characterized in that that she additional filler contains. Composition according to one of Claims 4 to 10, characterized in that that she additional solvent contains. Composition according to one of Claims 4 to 12, characterized in that that she additionally one Contains (meth) acrylamidoalkyl dihydrogen phosphate. Composition according to one of Claims 4 to 13, characterized in that that she a) 0.5 to 70 wt .-% acrylic ester phosphonic acid according to claim 1 or 2;  b) 0.01 to 15 wt .-% initiator for radical polymerization; c) 0 to 80 wt .-% radical polymerizable monomer; d) 0 to 95% by weight of solvent; e) 0 to 50% by weight, (meth) acrylamidoalkyl dihydrogen phosphate, and / or f) 0 to 75% by weight filler contains. Use of a composition according to any one of claims 4 to 14 as dental material. Use according to claim 15 as cement or adhesive. Use of an acrylic ester phosphonic acid according to any one of claims 1 to 3 for the production of a dental material.