Patented Nov. 5, 1940 2,220,845

UNITED STATES PATENT OFFICE 2,220,845 AROMATIC. PHOSPETES Clarence L. Moyle, Midland, Mich, assignor to The Dow Chemical Company, Midland, Mich., a corporation of Michigan No Drawing. Application August 12, 1938, Serial No. 224,635 11 Claims. (C. 260-461) This invention concerns certain new aromatic sents a different aromatic radical are prepared phosphites having the general formula: by first reacting the phosphorus trihalide with approximately two molecular equivalents of a phenol containing nine or more carbon atoms to form a di-aryl phosphorous acid non-halide and thereafter reacting such intermediate product with approximately one molecular equivalent of wherein R1 and R2 each represents an aromatic a different phenol to prepare the desired mixed radical containing at least nine carbon atoms triaryl phosphite. If desired, the order in which and R3 represents an aromatic radical. the reactions are carried out may be changed, 10 The new compounds herein disclosed are useful that is, the phosphorus trihalide may first be O as plasticizing agents for nitrocellulose, cellulose reacted with a phenol to form a mono-aryl phOS acetate, and cellulose ether, e. g. ethyl cellulose, phorus acid di-halide and the latter may then compositions. They are compatible with such be reacted with a different phenol containing cellulose derivatives, substantially non-volatile nine or more carbon atoms to form the mixed 15 at room temperatures, soluble or miscible in the triaryl phosphite product. 5 usual solvents or solvent mixtures for dissolving Unsymmetrical triaryl phosphites having the cellulose derivatives, and do not readily decom formula: pose or become discolored. Cellulose derivative compositions plasticized with the aforesaid new R-0 20 20 compounds are suitable for use in the prepara tion of artificial leather, lacquers, celluloid, films, R-07PR-O and molded articles, as well as for the other uses to which cellulose derivative compositions are wherein R1, R2, and R3 represent different aro ordinarily put. - matic radicals, at least two of which contain nine 25 The new phosphites having the above general or more carbon atoms, are prepared by reacting 25 formula are prepared by reacting a phosphorus the phosphorus trihalide successively with three trihalide, i. e. phosphorus trichloride, phosphorus different phenols, at least two of which contain tribromide, or phosphorus tri-iodide, with a nine or more carbon atoms. phenol containing at least nine carbon atoms, e. , All of the reactions mentioned above are car 30 g. p-isopropyl-phenol, o-cyclohexyl-phenol, beta ried out by heating a mixture of the reactants 30 naphthol, p-tertiary - butyl-phenol, m-phenyl to a temperature at which hydrogen halide is phenol, etc., and, if required, with other phenols, evolved. The reactions are preferably carried e.g. phenol, p-phenyl-phenol, 2,4-dibrom-phenol, out at the lowest convenient temperature, usu creosol, cresol, alpha-naphthol, carvacrol, p ally below 200° C., since at higher temperatures chlorphenol, o-methoxy-phenol, etc. by-product formation may occur to an objec 3. Symmetrical triaryl phosphites of the present tionable extent. If desired, a small proportion class, i. e. triaryl phosphites having the general of a catalyst, e. g. metallic magnesium, calcium, or aluminum, or a chloride of magnesium, alumi formula: - num, or iron, etc., may be employed. R-O In preparing mixed triaryl phosphites from a 40 R-OSP phosphorus trihalide and the necessary phenolic reactants, the intermediate phosphorous acid hal R-0 ide product may be separated and purified before wherein Rl represents an aromatic radical con carrying out the successive reactions. However, taining at least nine carbon atoms are prepared it is usually more convenient merely to distill 45 by reacting the phosphorus trihalide directly unreacted phosphorus trihalide from the impure with three or more molecular equivalents of a phosphorous acid halide, add the necessary pro phenol containing nine or more carbon atoms. portion of the second phenol, and continue the Mixed triaryl phosphites having the formula: reaction as hereinbefore described to form the final product. The latter consists largely of the 50 desired mixed triaryl phosphite, but may contain minor proportions of other mixed triaryl phos R-O phites as well as symmetrical triaryl phosphites wherein R1 represents an aromatic radical con formed by over-reaction of One or more of the a taining at least nine carbon atoms and R3 repre phenolic reactants. Such mixed product is 2 2,220,845 adapted to most uses for which the pure con Eacample 3 pound is suitable, and, accordingly, is a Com mercially valuable product. When desired, the A mixture of 943 grams (6 mols) of p-tertiary individual phosphites contained in such mixture butyl-phenol, and 275 grams (2 mols) of phos 5 can usually be separated by fractional distillation. phorus trichloride was heated at 84-160° C. for 5 In carrying out the invention, phosphorus tri 7 hours as in Example 1. Upon completion of chloride is usually employed as the phosphorus the reaction, 8 grams of anhydrous sodium car trihalide reactant, although any of the other bonate was added to neutralize the reaction mix phosphorus trihalides may be employed. The ture, and the latter was then fractionally dis 0 phenolic reactants employed in preparing the tilled. There was obtained tri-(p-tertiaryblid- 0 new products may contain substituents such as tylphenyl) phosphite, a colorless liquid distilling halogen, alkyl, alkoxy, aralkyl, or cycloalkyl Sub at approximately 288 to 294° C. under 8 milli Stituents, etc., which aire non-reactive With the meters pressure. Upon long Standing, this phosphorus trihalide under the conditions en product crystallizes to a White crystalline Solid 5 ployed, in which case correspondingly substi having a melting point of 75° to 76° C. It has 5 tuted triaryl phosphites will be obtained, the formula : The following examples will illustrate several Ways in, Winich the principle of the invention Analy be applied but are not to be construed as linite. 20 ing the same: Ecd.172ple 1 one-(D-o-o-O- (CH3)3 20 A mixture of 1650 grams (12 mols) of phos phorus trichloride and 680 grains (4 nois) of O-phenylphenol was heated at 74-78° C. for 2 hours, hydrogen chloride being evolved during 25 the reaction. When the reaction was complete, C (CH3)3 the excess phosphorus trichloride was distilled off, 921 grams being recovered. The crude aryl Eacample 4 phosphorus acid chloride product was cooled to a temperature of approximately 20° C. and 752 A mixture of 825 grams (5.25 mols) of p-ter- 30 grams (8 mols) of phenol was added. The tem tiarybutyl-phenol and 1650 grams (12 mols) of perature was gradually raised to 155° C. over a phosphorus trichloride was heated at 15° to 41 period of 8 hours until the evolution of hydrogen C. for i? hours as in Example 1. ExceSS phoS chloride gas had ceased. The mixture was then phorus trichloride was distilled from the reac 85 neutralized by addition of 16 grams of anhydrous tion mixture and 780 grams (8.3 mols) of p3:Aol 35 Sodium carbonate and the phosphite product was was added at approximately 5 C. The en recovered by fractional distillation. There was perature was gradually raised to 164 C. Over a, obtained di-(o-xenyl) mono-phenyl phosphite, a period of 9 hours, after which 16 grams of an pale yellow viscous liquid distilling at 308°-327 hydrous sodium carbonate was added to neutral 40 C. under 9 millimeters pressure, and having a ize the reaction mixture, and the latter was fraC- 40 Specific gravity of i.201 at 25/25° C. and an index tionally distilled. There was obtained di-(p-ter of refraction, tiarybutyl-phenyl) mono-phenyl phosphite, a n=1.6356 pale yellow viscous liquid distilling at approxi 45 Di- (o-xenyl) mono-phenylphosphite has the for mately 272-282° C. under 7 millimeters' pres mula: Sure, and having a specific gravity of 1.124 at 45 25/25° C. and an index of refraction, o-o- nig=1.5562 50 Di-(p-tertiarybutyl-phenyl) mono-phenyl phos- 50 phite has the formula:

55 t Eacample 2 one-(D-o-o-O- (CH3)3 55 A mixture of 1020 grams (6 mols) of o-phenyl phenol, 275 grams (2 mols) of phosphorus tri chloride and 1 gram of magnesium chloride was 60 heated at 75°-165° C. for 7% hours during which time hydrogen chloride was evolved. The reac 60 tion product was fractionally distilled to obtain Eacample 5 tri-(o-xenyl) phosphite as a fraction distilling at 336-340° C. under 5 millimeters pressure. This product is a slightly yellow viscous liquid which A mixture of 624 grams (6 mols) of o-cyclo gradually solidifies to a crystalline solid having hexylphenol and 275 grams (2 mols) of phos- 65 a melting point of 95° C. Tri-(o-xenyl) ph phorus trichloride was heated at 71°-161° C. for phite has the formula: .5% hours. Upon completion of reaction, 8 grams

of sodium carbonate was added to the crude re

O-P-O action mixture and the latter was fractionally 70 Co-cyclohexyl-phenyl)listilled under vacuum. phosphite, There was a colorlessobtained liqtri- 0. uid distilling at 324-329° C. under 8 millimeters preSSure and having an index of refraction,

75 n3-c 1.5580 75 2,220,845 3 Tri-Co-cyclohexyl-phenyl) phosphite has the therefore particularly point out and distinct formula: ly claim as my invention: 1. A triaryl phosphite having the general for mule, {---> R-0. B-02PR-O

wherein R1 and R2 each represents an aromatic O 10 radical containing at least 9 carbon atoms, and R3 represents an aromatic radical. 2. A triaryl phosphite having the general for mula: 5 R-O 6 R-O-PYN (2) A mixture of 1236 grams (6 mols) of p-ter tlaryoctylphenol and 275 grams (2 mols) of phos X > / 20 phorus trichloride was heated at 92-176° C. for wherein R1 and R2 each represents an aromatic 5% hours. After the addition of 3 grams of an radical containing at least 9 carbon atoms, Z. hydrous sodium carbonate, the crude reaction represents a substituent selected from the group mixture was fractionally distilled under vacuum. consisting of hydrogen, alkyl, aryl, cycloalkyl, and There was obtained tri-(p-tertiaryoctyl-phenyl) halogen substituents, and n represents an integer 25 phosphite, a colorless liquid distilling at 354-357 not greater than 3. C. under 10 millimeters pressure and having an 3. A triaryl phosphite having the general for index of refraction, mula: 80 n=1.5205 (X). and the formula: O no-KD-o-o-(D-on (Y),X X-O-GPN (2) / O

wherein X and Y each represents a different sH7 hydrocarbon substituent and is selected from the 40 Other triaryl phosphites of the present class group consisting of alkyl, aryl, and cycloalkyl 40 may be prepared by reacting a phosphorus tri radicals containing at least 3 carbon atoms, Z. halide with: (i) o-cyclohexyl-phenol and o represents a substituent selected from the group chlorphenol to form di-(o-cyclohexyl-phenyl) consisting of hydrogen, alkyl, aryl, cycloalkyl and mono-(o-chlorphenyl) phosphite; (2) carvacrol, halogen substituents, and m represents an integer 45 p-tertiaryoctyl-phenol, and o-cresol to form not greater than 3. 45 carvacryl p-tertiaryoctyl-phenyl o-cresyl phos 4. A symmetrical triaryl phosphite having the phite; (3) p-isopropyl-phenyl to form tri-(p-iso general formula: propyl-phenyl) phosphite; (4) thymol and alpha naphthol to form di-thymyl mono-(alpha-naph Ri- o, 50 thyl) phosphite; (5) cyclohexyl-cresol and 2,4-di R-O-P bromphenol to form di-(cyclohexyl-cresy) mono R-O (2,4-dibromphenyl) phosphite; (6)p-phenylphe nol and p-tertiarybutyl-phenol to form di-(p- wherein Ri represents an aromatic radical Con xenyl) mono-(p-tertiarybutyl-phenyl) phos tng at least 9 carbon atoms. 55 phite; () o-methoxyphenol, o-isoamylphenol, 5. A symmetrical triaryl phosphite having the and O-hexylphenol to form o-methoxy-phenyl o general formula: - isoamyl-phenyl o-hexyl-phenyl phosphite; (8) beta-naphthol and p-ethyl-phenol to form di (beta-naphthyl) mono-(p-ethyl-phenyl) phos 60 phite; (9) p-tertiarybutyl-phenol and m-brom (x > 0) phenol to form di-(p-tertiarybutylphenyl) mono wherein X represents a hydrocarbon substituent (m-bromphenyl) phosphite; (10) m-phenylphe selected from the group consisting of alkyl, aryl, nol, carvacrol, and 2,4,6-tribromphenol to form and cycloalkyl radicals containing at least 3 car m-xenyl carvacryl. 2,4,6-tribromphenyl phosphite; bon atoms, and n represents an integer not greater 65 (1) 2,4,6-triethyl-phenol to form tri(2,4,6-tri than 3. ethyl-phenyl) phosphite; etc. 6. A mixed triaryl phosphite having the gen This application is a continuation-in-part of eral formula: my co-pending application, Serial No. 172,63, filed November 1, 1937. R-0 70 Other modes of applying the principle of my 0 invention may be employed instead of those ex R-O plained, change being made as regards the Ima terial employed, provided the products stated by wherein each R1 represents the same aromatic any of the following claims or the equivalent of radical and contains at least 9 carbon atoms and 75 such stated products be obtained. , R3 represents a different aromatic radical. 5 4. 2,220,845 7. A mixed triaryl phosphite having the gen crystalline solid having a melting point of ap eral formula: proximately 75-76 C. and having the formula: R-O N R-O-P conc{D-o-o-C-con (2) O

O wherein R1 represents an aromatic radical con O taining at least 9 carbon atoms, Z represents a substituent Selected from the group consisting 10. Tri-(o-xenyl) phosphite, a crystalline solid of hydrogen, alkyl, aryl, cycloalkyl and halogen having a melting point of approximately 95 C. 5 substituents, and m represents an integer not and having the formula: greater than 3. s 8. A mixed triaryl phosphite having the gen eral formula: {>--- (X) 20 20 (X), 11. Di-(p-tertiarybutyl-phenyl) mono-phenyl 25 phosphite, a pale yellow viscous liquid distilling at 25 approximately 272-282° C. under 7 millimeters pressure, having a specific gravity of 1.124 at 25/25 C., and having the formula: wherein each X represents the same hydrocarbon 30 substituent and is selected from the group con sisting of alkyl, aryl, and cycloalkyl radicals con (choic-X D-O-P-O-( )-c (CH3)3 30 taining at least 3 carbon atoms, Z represents a O substituent selected from the group consisting of hydrogen, alkyl, aryl, cycloalkyl and halogen sub stituents, and m represents an integer not greater than 3. 3. 9. Tri-(p-tertiarybutylphenyl) phosphite, a CLARENCE L. MOYLE.