DD301615B5 - PROCESS FOR THE PRODUCTION OF ESTERS OF PHOSPHORIC AND PHOSPHONIC SAEURS - Google Patents

Description

Field of application of the invention

The invention relates to a process for the preparation of hydrolysis-stable esters of acids of the trivalent phosphorus, which can be advantageously used for stabilizing organic materials against a thermo and photooxidative degradation

Characteristic of the known state of the art

Esters of acids of the trivalent phosphorus are widely used, usually in combination with other additives (antioxidants, light stabilizers), as processing stabilizers for synthetic polymers. In addition to sterically hindered phosphites (inter alia DE 2 733 796, DD 146 961, DE -OS 2,944,254) cyclic phosphites (inter alia DD 146 464, DD 146 959, EP 0 032 681) A general disadvantage of most phosphites is their high sensitivity to hydrolysis, which limits the shelf life and the range of application. This hydrolysis can only be achieved in part by additions of amines (DE 2 135 238, DE 2 636 133), waxes (EP 2243) and soaps (DE 2 626 225) to push back the stabilizers, which, however, suffers the specific activity of the stabilizers There were also specific cyclic phosphites with a piperidine (DE -OS 2 656 999) or on the basis of Wemsaureestern with improved Hydrolysestabilitat described

DE-A 1 929 928 discloses the compound bis-2,2,6,6-tetramethyl-4-piperidyl) -phenyl-phosphite, but no preparation process is specified. The compound is used for stabilizing against photo- and thermal decomposition for synthetic Polymers applied

Object of the invention

The aim of the invention is to produce hitherto unknown open-chain esters of acids of trivalent phosphorus with improved hydrolysis stability in a simple manner in a simple manner

Explanation of the essence of the invention

The object of the invention is to develop a simple process for the preparation of hydrolysis-stable esters of acids of trivalent phosphorus (phosphites and phosphonites)

According to the invention, this object is achieved in that halides of trivalent phosphorus (phosphorus trichloride, phosphorus tribromide, mono-, dichlorophosphites or dichlorophosphines) gradually with a preferably sterically hindered phenol or phenol mixture and then with an aminoalcohol of the general structure I or II each in admixture with an excess of a tertiary amine in an inert, dry solvent, as defined in claim 1

(I)

R ₁ = hydrogen, oxyl, alkyl, alkenyl, aralkyl, alkoxyalkyl, alkoxyl

R ₂ , R ₃ , R ₄ , R ₅ = alkyl, cycloalkyl, phenyl or

R ₂ + R ₃ = R ₄ + R ₅ = tetra- or pentamethylene

r = 0 or 1

HO-YN ' _(||)

R ₁ = alkyl, cycloalkyl, aralkyl, phenyl

R ₂ = hydrogen, alkyl, cycloalkyl, aralkyl, phenyl

Y = aliphatic or cycloaliphatic carbon skeleton

In carrying out the process of the invention, the reaction can be conducted so that either the intermediates are isolated and further reacted separately or the reaction is realized as a one-pot reaction. The novel compounds according to the invention correspond to the general formulas III and IV.

^R 3 ^R 4

(R ₁ (Z) _n ^ -P- (O- (NR)

\ J ^{г u} (III)

R ₆ R ₅

R, = monosubstituted or polysubstituted phenyl

R ₂ = hydrogen, oxyl, alkyl, alkenyl, aralkyl, alkoxyalkyl, alkoxyl

R3. R4, Rs-Re = alkyl, cycloalkyl, phenyl or

R ₃ + R ₄ = R ₅ + R ₆ = tetra- or pentamethylene

η = 0 or 1 m + u = 3

Z = oxygen m = 1 or

r = O or 1 u = 1 or

(R ₁ (ZU-P- (OYN Cp ⁾ _u αν)

R, = mono- or poly-substituted phenyl

R ₂ = alkyl, cycloalkyl, aralkyl, phenyl

R ₃ = hydrogen, alkyl, cycloalkyl, aralkyl, phenyl

Y = aliphatic or cycloaliphatic carbon skeleton

η = 0 or 1 m + u = 3

Z = oxygen m = 1 or

u = 1 or

Surprisingly, it has been found that esters of acids of the trivalent phosphorus (phosphites and phosphonous), whose representatives with aliphatic radicals are normally particularly susceptible to hydrolysis, can be prepared which are also extremely stable to hydrolysis with one or two aliphatic radicals. It is a prerequisite that one or two ester groups derive from an aminoalcohol whose amino function is still very basic, but electronic and / or steric conditions make substitution reactions into stable end products very difficult. The compounds according to the invention are distinguished by a significantly better hydrolytic stability compared to other phosphorus stabilizers and thus a very good storage stability. They have good polymer compatibility and can be used as stabilizers for polymers. The effectiveness of the compounds of the invention as stabilizers is based on their ability to decompose hydroperoxides and to inhibit both thermally and photochemically initiated radical chain reactions, d. that is, they are able to act as primary and secondary antioxidants and also as sunscreens. Thus, an advantageous use alone or - for special applications - even in combination with other stabilizers possible.

applications example 1

Di- (2,2,6,6-tetramethylpiperidin-4-yl) -2,6-di-tert-butyl-4-methylphenylphosphit

0-ϊ-ίθ- / NH)

(1)

a) A solution of 26.5 g (0.12 mol) of 2,6-di-tert-butyl-4-methylphenol (BHT) in 22.5 g of triethylamine slowly under ice cooling (T <10 ⁰ C) to 85 g (0.62 mol) of phosphorus chloride is then added dropwise 17.5 g (0.08 mol) of BHT in the solid state added to the mixture After warming to room temperature, the reaction solution is kept under constant stirring for 3-4 h at 110 ⁰ C After cooling The solvent is then distilled off and the residue remaining for 1 h at 100 ⁰ C and 20 Torr on a rotary evaporator Finally, a rectification under a fine vacuum under nitrogen KP 110 ⁰ C (20 Pa )

b) 15.8 g (0.1 mol) of 2,2,6,6-tetramethylpholingen-4-ol are suspended with 11.2 g of triethylamine in 150 ml of dry benzene. If the room temperature is maintained, 16 g (0 , 05 mol) of phosphonic acid (2,6-di-tert-butyl-4-methylphenyl) ester dichloride shown under 1 a) is added dropwise The mixture is kept at 80 ° C, the amine hydrochloride abgefrittet and washed with benzene After distilling off the solvent the light yellow, glassy residue can be recrystallized from acetonitrile Phenol and Piperidinolfreiheit the product can be detected by means of high-pressure liquid chromatography The yield of the dichlorides used is 77% of theory

- ³¹ P-NMR 146.1 ppm (in o-dichlorobenzene), mp 126-127 ⁰ C.

Example 2

Di- (2,2,6,6-tetramethylpiperidm-4-yl) -2,6-di-tert-butyl-4-methylphenylphosphit

To a solution of 22 g (0.1 mol) of 2,6-di-tert-butyl-4-methylphenol and 13 g of triethylamine in 100 ml of dried toluene under ice cooling (T <10 "C) 42 g (0.305 mol) Phosphorus chloride in 50 ml of dry toluene was added dropwise

The mixture is stirred for 1 h at room temperature and 3 h under reflux

After cooling, the reaction solution is added dropwise synchronously 26 ml of triethylamine in about 200 ml of dry toluene and added portionwise 31.5 g (0.2 mol) of 2,2,6,6-tetramethylpiperidin-4-ol The mixture remains das.dehr 8 hours After the work-up of the solution as in Example 1, the triester is obtained in a yield of 65.5% with respect to

used phosphorus trichloride with о g constants

Example 3 to 7

Following the procedure given in Example 1 or 2, the compounds listed in Table 1 are shown

Table 1 example

Fp ( ⁰ C)

³¹ P NMR (ppm)

(3) Di (2,2,6,6-tetramethylpiperidin-4-yl) phenyl phosphite

(4) Di (2,2,6,6-tetramethylprepatin-4-yl) -phenylphosphonite

(5) Di- (2,2,6,6-tetramethylprepatin-4-yl) -2,4-di-tert-pentylphenyl phosphite

(6) Di (2,2,6,6-tetramethylpiperidm-4-yl) -2-tert-butyl-m-cresyl phosphite

(7) Di (2,2,6,6-tetramethylpiperidin-4-yl) -2,4 di-tert-butyl m-cresyl phosphite

Example 8

Di (2,4-di-tert-butyl m-cresyl) -2,2,6,6-tetramethylpiperidin-4-yl phosphite

61-62 138.2 (O-DCB) 79-80 152.1 (DCB) 55-57 137.9 (O-DCB) 63-64 134.1 (O-DCB) 73-74 133.7 (O-DCB)

о- ¹ Up-O- / WH

(2)

To a solution of 27.5 g (0.2 mol) of PCl ₃ in 150 ml dry η-hexane at room temperature (Wasserbadkuhlung) a suspension of 31.5 g (0.2 mol) of 2,2,6,6- Tetramethylpiperidine-4 oil, 44 g of triethylamine and 150 ml of dried n-hexane are added dropwise. The reaction mixture is stirred vigorously for 3 h at room temperature and under reflux for 5 h. Subsequently, 88 g (0.4 mol) of 2,4-di-tert-butyl- m-cresol in 200 ml of dry η-hexane added dropwise The mixture remains for a further 6 h at reflux After cooling the reaction solution, the hydrochloride is fritted, washed with η hexane After the

Distilling off the solvent leaves a tough, brownish residue, which can be recrystallized from an acetonitrile-ether mixture. The yield is 69% with respect to the phosphorus trichloride used. - ³¹ P-NMR: 128.6 ppm (o-DCB) mp: 164-165 ⁰ C.

Example 9

To test the hydrolytic stability of the compounds according to the invention, these and comparatively three simple phosphites were treated with an aqueous solution of o-dichlorobenzene and then analyzed for hydrolysis products (hydrogen phosphite, H ₃ PO ₃ ) using ³¹ P NMR spectroscopy. In each case, the solutions of 0.2 molar solution of phosphite and water in the presence of oxygen or nitrogen were stored in closed 200 ml Erlenmeyer flasks at 75 ° C. and analyzed at specific times. The results are shown in Table 2.

Table 2

connection

Time / h

O ₂ / N ₂

Hydrogen phosphite H ₃ PO ₃ Z ⁰ Z ₀

In-C ₈ H ₁₇ O) ₃ P

15

50

70

O,

0

85.5 69.3

61 76

Tracks traces

19 21

The compounds (1), (4), (5), (6), (7), (8) according to the invention exhibit neither oxygen nor nitrogen after 70 h

Hydrolysis products on.

Additional technical information can be found in the patent file.

Claims (2)

claims: R ₁ R ₂ R ₃ mean, and m + u characterized in that as ester groups of said acids one or two of aminoalcohols of the formula I or II = monosubstituted or polysubstituted phenyl = Alkyl, cycloalkyl, aralkyl, phenyl = Hydrogen, alkyl, cycloalkyl, aralkyl, phenyl = aliphatic or cycloaliphatic carbon skeleton = 0 or 1 = Oxygen = 1 or 2 = 1 or 2 = 3, wherein
R ₁ R ₂ , R ₃ , R ₄ , R ₅
R ₂ + R ₃ = R ₄ + R ₅ r
mean NO, (D = Hydrogen, oxyl, alkyl, alkenyl, aralkyl, alkoxyalkyl, alkoxyl = alkyl, cycloalkyl, phenyl or
= Tetra- or pentamethylene
= 0 or 1 or ΗΟ-Υ-Ν ((ID wherein R ₁ = alkyl, cycloalkyl, aralkyl, phenyl
R ₂ = hydrogen, alkyl, cycloalkyl, aralkyl, phenyl
Y = aliphatic or cycloaliphatic carbon skeleton derived radicals, by reaction of halides of the trivalent phosphorus stepwise - preferably - with a sterically hindered phenol and then with the amino alcohol incorporated. 2. The method according to claim 1, characterized in that are used as halides of trivalent phosphorus PCI ₃ , PBr ₃ , dichlorophosphites, Monochlorphoshite and dichlorophosphines.