United States Patent (113,627,798 72 Inventor Laird Gordon Lindsay Ward 3,321,502 5/1967 Soeder ......................... 260/439 Suffern, N.Y. (21) Appl. No. 869,905 3,346,447 10/1967 Wright........ - - 167/31 22 Filed Oct. 27, 1969 3,390,160 6/1968 Heller et al.. 260/433 45) Patented Dec. 14, 1971 3,437,620 4/1969 Yamamoto................... 260/23 (73) Assignee The International Nickel Company, Inc. OTHER REFERENCES New York, N.Y. Teramura et al. Chem. Abst. 68 p. 1360, abstract of Japanese Patent 5424- (67) Kirk- Othmer, Encyclopedia of Chemical Technology In (54) PROCESS FOR PREPARING THE NICKEL terscience Publishers, N.Y., N.Y., Vol. 13, 1967, p. 754-755 DERVATIVES OF METHYLENEBSPHENOL Primary Examiner-Tobias E. Levow 11 Claims, NoDrawings Assistant Examiner-A. P. Demers 52) U.S. Cl........................................................ 260/439 R, Attorney-Maurice L. Pinel 260/45.75 N (51) int. Cl......................................................... C07f 15/04, C08f 45/62 ABSTRACT: A process for preparing nickel derivatives of (50) Field of Search............................................ 260/439, methylene bisphenols in which a methylene bisphenol, a 45.75 N; 252/42.7 Group a metal alkoxide and a nickel salt are reacted in an es sentially nonaqueous environment, and the nickel derivative is (56) References Cited precipitated from solution. Novel nickel derivatives of UNITED STATES PATENTS methylene bisphenol, e.g., nickel hexachlorophene, are effec 2,971,968 2/1961 Nicholson et al............. 260/439 tive as light stabilizing additives in vinyl polymers. 3,627,798 1 2 PROCESS FOR PREPARNGTHENICKELDERVATIVES ing of methanol, ethanol, propanol, isopropanol, n-butanol, OFMETHYLENEBSPHENOL isobutanol, sec-butanol, acetone, tetrahydrofuran, dimethox This invention relates to a novel process for preparing yethane and dimethylformamide; and precipitating the nickel nickel compounds which are derivatives of methylene derivative. bisphenols and, more particularly, to novel stabilizing com 5 The methylene bisphenol used in the process is beneficially pounds for vinyl polymers, such as polyvinylchloride. hexachlorophene having the general structure, Attempts to prepare nickel salts of methylene bisphenols, HO OH such as hexachlorophene, in aqueous media, have thus far not met with success. It is desirable that a method suitable for the Cl -CH- -Cl preparation of such compounds be provided. O Polyvinylchloride (PVC) and related vinyl polymers are -Cl Cl light sensitive and suffer degradation including both discolora tion and embrittlement upon exposure to light, Many attempts Cl Cl have been made to stabilize these polymers by introducing although other suitable methylene bisphenols can be em various additives, and improvement in the stability of these 15 ployed. With regard to the Group a metal alkoxide, rubidium materials upon exposure to light has been achieved in some and cesium are highly reactive Group a metals and for that cases. However, more effective and more economical stabil reason are less desirable for the contemplated reaction to izers are needed. produce an alkoxide. Also, rubidium chloride is not very solu A new process has now been discovered in which a ble in alcohol, and cesium chloride is quite hygroscopic, these methylene bisphenol, a Group a metal alkoxide and a nickel 20 properties being disadvantageous in the reactions of the inven halide are reacted to precipitate a nickel derivative of tion as will be more fully explained hereinafter. While the an methylene bisphenol. hydrous nickel halide can be used in its pure form as a reac It has further been discovered that the novel compounds tant to the extent that it is soluble in the nonaqueous solvent, it prepared by the process of the invention are useful as light sta is advantageous to provide the nickel halide in the more solu bilizers for vinyl polymers. 25 ble form of an anhydrous organic complex. Such a soluble or It is an object of the invention to provide a process for mak ganic complex may be prepared by reacting the hydrated ing the nickel derivative of hexachlorophene. nickel halide (chloride, bromide or iodide) with peroxide Another object of the invention is to provide a vinyl free, ethylene-glycol dimethylether (monoglyme). The polymer having improved stabilization characteristics against 30 product of this reaction is nickel halide dimethoxyethanate degradation by light. (nickel halide. EGDE complex). The nickel halide. EGDE Other objects and advantages will become apparent from complex is quite soluble in alcohol and it is also soluble in the following description. acetone, tetrahydrofuran, dimethoxyethane and dimethyl Generally speaking, the present invention contemplates a formamide. process for making nickel derivatives of methylene bisphenols 35 The alcohols employed in the process, which desirably con having the general formula, tain from one to four carbon atoms, may function as solvents as well as reactants, i.e., the stoichiometric amount of alcohol HO O-Ni-O gh functioning as a reactant while the excess alcohol functions as a solvent. Alcohols having more than four carbons atoms are R CH R. R- CH R 40 less reactive at the reaction temperatures characterizing this process and, for that reason, are not as well suited for use as R -R. R. -R. R. -R. R. -R solvents, although they will react with the alkali metal. Al cohols having up to 12 carbon atoms may be used as reactants, R R R R but the increasing viscosity of the higher alcohols, e.g., 45 isoamyl alcohol, slows the desired reactions, and the system may have to be heated to obtain the reaction. Further, no par in which R is selected from the group consisting of hydrogen; ticular benefit is secured by employing the higher alcohols. halogens, e.g., chlorine; alkyls, e.g., butyl; substituted alkyls, Under normal conditions, the tert-butyl alcohol does not react e.g., tertiary butyl; aryls, e.g., phenyl; alkylaryls, e.g., with lithium or sodium. methylphenyl; arylalkyls, e.g., benzyl; or combinations 50 In order to obtain a relatively pure product upon precipita thereof. The compounds provided in accordance with the in tion of the nickel derivatives of methylene bisphenols from vention are useful as light stabilizing additives for vinyl solution, it will be understood that the byproduct of the reac polymers such as polyvinylchloride and polyvinyl acetate. tion, i.e., the alkali metal halide, must be soluble in the solvent More particularly, the nickel derivatives of methylene employed to facilitate separation of the product from the bisphenols are prepared by reacting a methylene bisphenol 55 byproduct. Since alcohols are advantageous solvents, it will be having the general formula, apparent that reactants which result in the production of HO OH byproducts which are relatively insoluble, or only slightly solu ble, in alcohol, such as lithium fluoride, sodium fluoride, sodi R- -CH- -R um chloride, sodium bromide, potassium fluoride, potassium 60 chloride, potassium bromide rubidium fluoride, rubidium bro R -R. R. -R mide and cesium fluoride, are unsuitable for the practice of this process, if an alcohol is used assolvent. R R It is possible, though less convenient, to use other solvents in which R is selected from the group consisting of hydrogen; 65 in the process (with alcohol functioning only as a reactant) in halogens, e.g., chlorine; alkyls, e.g., butyl; substituted alkyls, cluding acetone, tetrahydrofuran, dimethoxyethane and e.g., tertiary butyl; aryls, e.g., phenyl; alkylaryls, e.g., dimethylformamide. The nickel halide EGDE complex and methylphenyl; arylalkyls, e.g., benzyl; or combinations the byproduct alkali metal halides such as lithium chloride, thereof; a Group a metal alkoxide, which advantageously is lithium iodide, lithium bromide, sodium iodide, potassium the reaction product of a Group a metal, e.g., lithium, sodium 70 iodide, rubidium iodide, cesium chloride, cesium bromide and or potassium, and an alcohol having from one to four carbon cesium iodide will dissolve in these solvents. atoms, e.g., methanol, ethanol, propanol, isopropanol, n-bu The sequence in which the reactions of the invention are tanol, isobutanol or sec-butanol; and an anhydrous, or sub conducted is of significant importance. Thus, the methylene stantially anhydrous, nickel halide; in an essentially nonaque bisphenol is first reacted with the Group a metal alkoxide to ous solvent, particularly one selected from the group consist 75 form a Group a metal methylene bisphenolate. The Group a 3,627,798 3 4. metal methylene bisphenolate is reacted with a nickel dihalide Preparation of Nickel Hexachlorophenate whereupon the Group a metal ions of two molecules of the bisphenolate are replaced by nickel which links the two Nickel di-(2,2')-methylene-3,4,6-Trichlorophenol-3,4,6'- molecules, and the products of the reaction are nickel trichlorophenate '6CHOH dimethylene bisphenolate and a Group a metal halide. A 8 grams (1.2 g atom) of lithium was added to a flask con direct reaction does not readily occur between nickel dihalide taining 1,500 milliliters of absolute methanol under a nitrogen and methylene bisphenol because there is insufficient driving atmosphere producing a solution of lithium methoxide. The force for this reaction. solution of lithium methoxide was refluxed at 65 C. and dur The desired reactions do not occur when attempted in aque ing this operation 488 grams (1.2 moles) of hexachlorophene ous solution. It has been found, for example, that, in aqueous 10 was added. This mixture was refluxed at 65 C. for 0.5 hour solution, precipitation of hexachlorophene occurs if the pH of and then a solution of 186 grams (0.6 mole) of anhydrous the solution falls below approximately 8. On the other hand, nickel bromide. EGDE complex in 600 milliliters of methanol when the pH of the solution is raised to keep hexachlorophene was added. The hot (55 C.) yellow-green reaction mixture in solution, nickel hydroxide is formed and the desired 15 was then reduced to a volume of about 1.5 liters and then product, nickel hexachlorophenate, is not achieved.