US3424789A - Process for oxidizing a 1,1-bis-(alkyl-phenyl)alkane - Google Patents

Process for oxidizing a 1,1-bis-(alkyl-phenyl)alkane Download PDF

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US3424789A
US3424789A US349767A US3424789DA US3424789A US 3424789 A US3424789 A US 3424789A US 349767 A US349767 A US 349767A US 3424789D A US3424789D A US 3424789DA US 3424789 A US3424789 A US 3424789A
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bis
percent
carboxylic acid
benzophenone
oxidizing
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Johann G D Schulz
Arthur C Whitaker
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Chevron USA Inc
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Gulf Research and Development Co
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
    • C07C51/16—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation
    • C07C51/21—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen
    • C07C51/255—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen of compounds containing six-membered aromatic rings without ring-splitting
    • C07C51/265—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen of compounds containing six-membered aromatic rings without ring-splitting having alkyl side chains which are oxidised to carboxyl groups
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/27—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation
    • C07C45/32—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation with molecular oxygen
    • C07C45/33—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation with molecular oxygen of CHx-moieties
    • C07C45/34—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation with molecular oxygen of CHx-moieties in unsaturated compounds
    • C07C45/36—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation with molecular oxygen of CHx-moieties in unsaturated compounds in compounds containing six-membered aromatic rings
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
    • C07C51/16—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation
    • C07C51/27—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with oxides of nitrogen or nitrogen-containing mineral acids
    • C07C51/275—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with oxides of nitrogen or nitrogen-containing mineral acids of hydrocarbyl groups

Definitions

  • the 1,1-bis-(alkylphenyl) alkane that is subjected to oxidation with molecular oxygen is one wherein said alkyl has from one to 16 carbon atoms, preferably from one to eight carbon atoms, and said alkane has from two to 16 carbon atoms, preferably from two to eight carbon atoms.
  • 1,l-bis-(alkylphenyl) alkanes that can be employed are 1,1-bis-(p-tolyl) ethane, 1,1-bis-(ptolyl) propane, l,l-bis-(ptolyl) butane, 1,1-bis-(p-tolyl) hexane, 1,1-bis-(p-tolyl) octane, 1,1-bis-(p-tolyl) decane, 1,1-bis-(p-tolyl) dodecane, 1,1-bis-(p-tolyl) tetradecane, 1,1-bis-(p tolyl) hexadecane, 1,1 bis (4 ethylphenyl) ethane, 1,1-bis-(4-octylphenyl) pentane, 1,1-bis-(4-decylphenyl) octane, l,l-bis-(4-hex
  • the oxidation of a bis-(alkylphenyl) methane with molecular oxygen in the presence of catalytic amounts of a catalyst, such as cobalt acetate, can proceed without undue difiiculty to the corresponding benzophenone carboxylic acid.
  • a catalyst such as cobalt acetate
  • the hydroperoxide portion is unstable and cleavage occurs between the adjacent oxygen atoms, thereby producing a diphenylmethoxy radical.
  • the hydrogen attached to the bridge carbon has a greater migration aptitude than either of the phenyl groups attached to said bridge carbon, said hydrogen will preferentially split off.
  • the alkyl substituents on the ring will also be oxidized to obtain carboxylic acid functions and as a result of these actions a benzophenone carboxylic acid is formed and water is obtained as a by-product.
  • the migration aptitude of the phenyl groups attached to the bridge carbon is greater than the migration aptitude of the alkyl substituent attached to said bridge carbon and therefore there is a tendency for one of the phenyl groups to leave and form a phenol and to obtain an acetophenone as an additional product.
  • the reaction defined herein can be carried out by bringing together the 1,1-bis-(alkylphenyl) alkane defined above and molecular oxygen such as air, preferably by passing the latter therethrough, at moderate temperatures and pressures in the presence of a selected amount of catalyst.
  • the total amount of oxygen required per total mol of charge to be oxidized is at least about one, but preferably about eight to about 16 mols.
  • the temperature of the reaction can be as low as about 25 C., but in order to obtain a reasonable reaction rate we prefer to employ a temperature of at least about 50 C. Temperatures as high as about 110 C. can be employed, but in order to inhibit the formation of undesirable by-products we prefer to employ a temperature no higher than about C.
  • the length of the reaction period is dependent upon the nature of the product desired.
  • the hydroperoxide defined decomposes, the following desired compounds are formed: a 1,1-bis-(alkylphenyl) alkylene, a 1,1-bis-(alkylphenyl) alkylcarbinol, an alkylbenzophenone and an alkylbenzophenone mono carboxylic acid.
  • a small amount of the following undesired compounds are also formed: phenols and acetophenones.
  • the first three compounds defined in the list of desired compounds are precursors to the alkylbenzophenone mono carboxylic acid, and therefore with increased reaction time more of the desired benzophenone mono carboxylic acid is obtained, until continued oxidation results in a large conversion of the charge to benzophenone mono carboxylic acid and/or to a benzophenone carboxylic acid.
  • a reaction time of at least about 30 minutes, but preferably of about five to about 24 hours, is suflicient for the stated purposes.
  • the amount of catalyst needed is the amount catalytically required to obtain the desired hydroperoxide and an additional amount sufiicient selectively to obtain the desired benzophenone, rather than the phenol and/or acetophenone, and to convert at least a portion of the alkyl substituents on the rings to the carboxylic acid function.
  • the amount of catalyst in the reaction system is from about 0.02 to about 10, preferably from about one to about five percent by weight relative to the 1,1-bis-(alkylphenyl) alkane charge. Best results are obtained when about three percent by weight of catalyst is employed.
  • catalysts for the process we prefer to employ a salt of an organic acid and a transition metal soluble in the reaction mixture.
  • organic acid we mean to include straight chain and cyclic organic acids having from six to 20 carbon atoms in the molecule.
  • examples of such acids are hexanoic acid, octanoic acid, stearic acid, naphthenic acids, etc.
  • examples of such metals are iron, cobalt, nickel, manganese, chromium, vanadium, molybdenum, etc.
  • catalysts which can be employed include ferrous caprylate, cobaltous caprylate, cobaltous naphthenate, nickelous naphthenate, manganese caprylate, manganese naphthenate, chromous stearate, chromous hexanoate, vanadium naphthenate, molybdenum caprylate, molybdenum stearate, etc.
  • the work-up of the product thus obtained depends upon the nature thereof and the type of ultimate product desired.
  • the entire air oxidation product can be further oxidized with nitric acid. This can be done, for example, by oxidizing the same with nitric acid having a concentration of from about five to about 70 percent, with the molar ratio of the nitric acid to the compound to be oxidized being from about 8.0 to about 17.0.
  • the reaction temperature can be from about 110 to about 350 C., the reaction pressure from about atmospheric to about 500 pounds per square inch gauge and the reaction time from about one minute to about 48 hours.
  • the partially oxidized benzophenone carboxylic acid can be separated from the air-oxidized product and then subjected to oxidation with nitric acid in the manner described above.
  • This separation can be effected by adding to the reaction mixture from about to about 50 percent by weight of benzene and sufiicient alkali, such as sodium hydroxide, to react with the benzophenone carboxylic acids and small amounts of cleavage products of phenolic nature present therein, such as alkyl phenols.
  • An organic phase containbenzophenone and an aqueous alkaline phase containing the partially and/or fully oxidized benzophenone carboxylic acid and said cleavage products of phenolic nature are thus obtained.
  • the two phases so obtained are separated from each other, and the alkaline phase is treated with at least the stoichiometric amounts of an inorganic acid such as hydrochloric acid, at a temperature of about 10 to about C. to thereby precipitate the phenolic products and the benzophenone carboxylic acid.
  • the precipitate is separated from the solution and treated with an aqueous solution of sodium bicarbonate. While the phenols will not be solubilized thereby, the alkaline metal salt of the benzophenone carboxylic acid will be solubilized. After separation of the phenolic products therefrom the solution can be treated with an inorganic acid to precipitate the benzophenone carboxylic acid.
  • the organic layer described above after removal of benzene therefrom by evaporation and upon standing at a temperature of about 0 to about 35 C. will result in the precipitation therein of the alkylbenzophenone, and the separation of the latter therefrom can be effected by filtration.
  • the remainder of the organic layer can be diluted with an alcohol, such as methyl alcohol, and on cooling to a temperature of about 50 to about '10 C., removal of the 1,1-bis-(alkylphenyl) alkylene as a solid precipitate results.
  • the residual organic layer can then be extracted with glycol which results in the removal therefrom of the 1,1-bis-(alkylphenyl) alkylcarbinol.
  • the remainder is 1,1-bis-(alkylphenyl) alkane which is then recovered.
  • TAB LE I Percent Weight percent Percent Percent efiiciency to Percent Run No. Time, of charge efficiency to efficiency to benzophenone etficiency to hours converted alcohol and alk mono by-products olefin benzophenone carboxylic acid ing benzene, unreacted charge, 1,1-bis-(alkylphenyl) alkylene, 1,1-bis-(alkylphenyl) alkylcarbinol and alkyl- In Table II below the effect of reaction time at 95 is illustrated.
  • EXAMPLE I 191.0 grains of dixylylethane, 6.3 grams of cobaltous caprylate (3.33 weight percent) and 2.7 grams of methyl TABLE VII Percent Percent Percent Weight percent eiliciency efficiency efliciency to Percent Run No. Cation of charge to alcohol to elkyl benzophenone efliciency converted and olefin benzophenone mono cargoxyhc to lay-products aci DXE 44 .7 58.60 12.22 26.62 2.52 DTE 34 .4 52 .01 14 .63 26 .31 7 .01
  • alkyl benzophenone mono carboxylic acid in the air oxidized reaction mixture can be treated with.
  • nitric acid for the defined purpose can be seen from the following.
  • EXAMPLE II 191.0 grams of dixylylethane, 12.6 grams of cobaltous caprylate and 5.7 grams of methyl ethyl ketone were contacted with molecular oxygen at the rate of 100 cc. of oxygen per minute over a period of seven hours at a temperature ranging between 90 and 95 C. at atmospheric pressure. By alkaline treatment of the reaction mixture obtained there was recovered trimethyl benzophenone mono carboxylic acid. 67.0 grams of the latter acid was reacted in a one-liter stirred autoclave with 538.0 grams of 30 percent nitric acid at 170 C. and 200 pounds per square inch gauge for two hours. There was found 62.0 grams of 3,4,3',4-benzophenone tetracarboxylic acid.
  • EXAMPLE III 510.0 grams of dixylylethane, 17.0 grams of cobaltous caprylate and 7.2 grams of methyl ethyl ketone were contacted with molecular oxygen at the rate of 100 cc. of oxygen per minute over a period of 16 hours at a temperature ranging between 60 and 65 C. at atmospheric pressure.
  • the reaction product was treated with an aqueous alkaline solution and subsequently extracted with benzene. Two phases, an alkaline soluble phase and a benzene soluble phase, were obtained. From the latter after evaporation of the solvent 3,4,3',4'-tetramethyl benzophenone was collected.
  • a process for oxidizing a 1,1-bis-(alkylphenyl) alkane wherein said alkane has at least two carbon atoms which comprises oxidizing the same with molecular oxygen at a temperature of about 25 to about 110 C. in the presence of about 0.10 to about percent by weight of a transition metal salt of a carboxylic acid to obtain a mixture containing a benzophenone carboxylic acid.
  • a process for oxidizing a 1,1-bis-(alkylphenyl) alkane wherein said alkane has at least two carbon atoms which comprises oxidizing the same with molecular oxygen at a temperature of about 25 to about 110 C. in the presence of about 0.10 to about 10 percent by weight of a cobalt salt of a carboxylic acid to obtain a mixture containing a benzophenone carboxylic acid.
  • a process for oxidizing a 1,1-bis-(alkylphenyl) alkane wherein said alkane has at least two carbon atoms which comprises oxidizing the same with molecular oxygen at a temperature of about 25 to about 110 C. in the presence of about 0.10 to about 10 percent by weight of a manganese salt of a carboxylic acid to obtain a mixture containing a benzophenone carboxylic acid.
  • a process for oxidizing a 1,1-bis-(alkylphenyl) alkane wherein said alkane has at least two carbon atoms which comprises oxidizing the same with molecular oxygen at a temperature of about 25 to about 110 C.
  • a process for oxidizing a 1,1-bis-(alkylphenyl) alkane wherein said alkane has at least two carbon atoms which comprises oxidizing the same with molecular oxygen at a temperature of about 25 to about C. in the presence of about 0.10 to about 10 percent by weight of cobalt caprylate to obtain a mixture containing a benzophenone carboxylic acid.
  • a process for oxidizing a 1,1-bis-(alkylphenyl) alkane wherein said alkane has at least two carbon atoms which comprises oxidizing the same with molecular oxygen at a temperature of about 25 to about 110 C. in the presence of about 0.10 to about 10 percent by weight of manganese caprylate to obtain a mixture containing a benzophenone carboxylic acid.
  • a process for oxidizing a 1,1-bis-(alkylphenyl) alkane wherein said alkane has at least two carbon atoms which comprises oxidizing the same with molecular oxygen at a temperature of about 25 to about 110 C. in the presence of about 0.10 to about 10 percent by weight of ferrous caprylate to obtain a mixture containing a benzophenone carboxylic acid.
  • a process for oxidizing ditolylethane which comprises oxidizing the same with molecular oxygen at a temperature of about 25 to about 110 C. in the presence of about one to about 10 percent by weight of a transition metal salt of a carboxylic acid to obtain a mixture containing a benzophenone carboxylic acid.
  • a process for oxidizing ditolylethane which comprises oxidizing the same with molecular oxygen at a temperature of about 25 to about 110 C. in the presence of about one to about 10 percent by weight of cobalt caprylate to obtain a mixture containing a benzophenone carboxylic acid.
  • a process for oxidizing ditolylethane which comprises oxidizing the same with molecular oxygen at a temperature of about 25 to about 110 C. in the presence of about one to about 10 percent by weight of manganese caprylate to obtain a mixture containing a benzophenone carboxylic acid.
  • a process for oxidizing ditolylethane which comprises oxidizing the same with molecular oxygen at a temperature of about 25 to about 110 C. in the pres ence of about one to about 10 percent by weight of ferrous caprylate to obtain a mixture containing a benzophenone carboxylic acid.
  • a process for oxidizing dixylylethane which comprises oxidizing the same with molecular oxygen at a temperature of about 25 to about 110 C. in the presence of about one to about 10 percent by weight a transition metal salt of a carboxylic acid to obtain a mixture containing a benzophenone carboxylic acid.
  • a process for oxidizing dixylylethane which comprises oxidizing the same with molecular oxygen at a temperature of about 25 to about 110 C. in the presence of about one to about 10 percent by weight of cobalt caprylate to obtain a mixture containing a benzophenone carboxylic acid.
  • a process for oxidizing dixylylethane which comprises oxidizing the same with molecular oxygen at a temperature of about 25 to about 110 C. in the presence of about one to about 10 percent by weight of manganese caprylate to obtain a mixture containing a benzophenone carboxylic acid.
  • a process for oxidizing dixylylethane which comprises oxidizing the same with molecular oxygen at a temperature of about 25 to about 110 C. in the presence of about one to about 10 percent by weight of felrous caprylate to obtain a mixture containing a benzophenone carboxylic acid.
  • a process for oxidizing a 1,1-bis-(alkylphenyl) alkane wherein said alkane has at least two carbon atoms which comprises oxidizing the same with molecular oxygen at a temperature of about 25 to about 110 C. in the presence of about one to about 10 percent by weight of a transition metal salt of a carboxylic acid to obtain a mixture containing a benzophenone cauboxylic acid and thereafter oxidizing said mixture with nitric acid.
  • a process for oxidizing ditolylethane which comprises oxidizing the sarne with molecular oxygen at a temperature of about 25 to about 110 C. in the presence of about one to about 10 percent by weight a transition metal salt of a carboxylic acid to obtain a mixture containing a benzophenone carboxylic acid and thereafter oxidizing said mixture with nitric acid.
  • a process for oxidizing dixylylethane which comprises oxidizing the same with molecular oxygen at a temperature of about 25 to about 110 C. in the presence of about one to about 10 percent by weight of a transition metal salt of a carboxylic acid to obtain a mixture containing a benzophenone carboxylic acid and thereafter oxidizing said mixture with nitric acid.

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US349767A 1964-03-05 1964-03-05 Process for oxidizing a 1,1-bis-(alkyl-phenyl)alkane Expired - Lifetime US3424789A (en)

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US (1) US3424789A (en, 2012)
BE (1) BE660630A (en, 2012)
DE (1) DE1518920A1 (en, 2012)
FR (1) FR1425135A (en, 2012)
GB (1) GB1073884A (en, 2012)
LU (1) LU48115A1 (en, 2012)
NL (1) NL6502854A (en, 2012)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4244881A (en) * 1978-03-29 1981-01-13 Montedison S.P.A. Process for preparing alpha-naphthol esters of aliphatic carboxylic acids
US4299987A (en) * 1977-11-14 1981-11-10 The Standard Oil Company Process for producing benzo-phenone from 1,1-diphenylethane (or 1,1-diphenylethylene) using antimonate catalysts

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE533179A (en, 2012) * 1954-11-26 1954-11-30
US3075007A (en) * 1959-06-24 1963-01-22 Gulf Research Development Co Nitric acid oxidation of 1,1-diarylalkanes to produce carboxy substituted diaryl ketones

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE533179A (en, 2012) * 1954-11-26 1954-11-30
US3075007A (en) * 1959-06-24 1963-01-22 Gulf Research Development Co Nitric acid oxidation of 1,1-diarylalkanes to produce carboxy substituted diaryl ketones

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4299987A (en) * 1977-11-14 1981-11-10 The Standard Oil Company Process for producing benzo-phenone from 1,1-diphenylethane (or 1,1-diphenylethylene) using antimonate catalysts
US4244881A (en) * 1978-03-29 1981-01-13 Montedison S.P.A. Process for preparing alpha-naphthol esters of aliphatic carboxylic acids

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FR1425135A (fr) 1966-01-14
LU48115A1 (en, 2012) 1965-05-03
DE1518920A1 (de) 1969-06-12
GB1073884A (en) 1967-06-28
BE660630A (en, 2012) 1965-07-01
NL6502854A (en, 2012) 1965-09-06

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