US2776321A - Mgnoetherification of mono-tertiary- - Google Patents
Mgnoetherification of mono-tertiary- Download PDFInfo
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- US2776321A US2776321A US2776321DA US2776321A US 2776321 A US2776321 A US 2776321A US 2776321D A US2776321D A US 2776321DA US 2776321 A US2776321 A US 2776321A
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- reaction
- tertiarybutyl
- mono
- alkylating
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- 238000006243 chemical reaction Methods 0.000 claims description 78
- 238000000034 method Methods 0.000 claims description 52
- 239000000203 mixture Substances 0.000 claims description 22
- 238000010992 reflux Methods 0.000 claims description 22
- 239000007791 liquid phase Substances 0.000 claims description 18
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 claims description 12
- 150000008044 alkali metal hydroxides Chemical class 0.000 claims description 10
- 150000008050 dialkyl sulfates Chemical class 0.000 claims description 10
- 150000004945 aromatic hydrocarbons Chemical class 0.000 claims description 8
- 239000012298 atmosphere Substances 0.000 claims description 8
- OKTJSMMVPCPJKN-UHFFFAOYSA-N carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 8
- 239000012429 reaction media Substances 0.000 claims description 8
- 150000001338 aliphatic hydrocarbons Chemical class 0.000 claims description 6
- 239000002168 alkylating agent Substances 0.000 claims description 6
- 229910052799 carbon Inorganic materials 0.000 claims description 6
- 230000002152 alkylating Effects 0.000 claims description 4
- 239000003054 catalyst Substances 0.000 claims description 4
- 239000012071 phase Substances 0.000 claims description 4
- XRCRJFOGPCJKPF-UHFFFAOYSA-N 2-butylbenzene-1,4-diol Chemical compound CCCCC1=CC(O)=CC=C1O XRCRJFOGPCJKPF-UHFFFAOYSA-N 0.000 claims 2
- HEMHJVSKTPXQMS-UHFFFAOYSA-M sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 42
- 239000002904 solvent Substances 0.000 description 42
- BGNXCDMCOKJUMV-UHFFFAOYSA-N TBHQ Chemical compound CC(C)(C)C1=CC(O)=CC=C1O BGNXCDMCOKJUMV-UHFFFAOYSA-N 0.000 description 36
- 238000006266 etherification reaction Methods 0.000 description 32
- 239000000463 material Substances 0.000 description 28
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 28
- 239000003795 chemical substances by application Substances 0.000 description 24
- HCHKCACWOHOZIP-UHFFFAOYSA-N zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 24
- 239000003518 caustics Substances 0.000 description 22
- YXFVVABEGXRONW-UHFFFAOYSA-N toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 20
- VAYGXNSJCAHWJZ-UHFFFAOYSA-N Dimethyl sulfate Chemical compound COS(=O)(=O)OC VAYGXNSJCAHWJZ-UHFFFAOYSA-N 0.000 description 18
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 16
- QIGBRXMKCJKVMJ-UHFFFAOYSA-N benzohydroquinone Chemical compound OC1=CC=C(O)C=C1 QIGBRXMKCJKVMJ-UHFFFAOYSA-N 0.000 description 16
- 239000011541 reaction mixture Substances 0.000 description 16
- 239000007795 chemical reaction product Substances 0.000 description 14
- ALVJDUNBMKMTDC-UHFFFAOYSA-N 2-tert-butyl-1,4-dimethoxybenzene Chemical compound COC1=CC=C(OC)C(C(C)(C)C)=C1 ALVJDUNBMKMTDC-UHFFFAOYSA-N 0.000 description 12
- 239000002253 acid Substances 0.000 description 12
- 150000002430 hydrocarbons Chemical class 0.000 description 12
- 239000000047 product Substances 0.000 description 12
- 230000001681 protective Effects 0.000 description 12
- IMOYOUMVYICGCA-UHFFFAOYSA-N 2-tert-butyl-4-hydroxyanisole Chemical compound COC1=CC=C(O)C=C1C(C)(C)C IMOYOUMVYICGCA-UHFFFAOYSA-N 0.000 description 10
- IMNFDUFMRHMDMM-UHFFFAOYSA-N n-heptane Chemical compound CCCCCCC IMNFDUFMRHMDMM-UHFFFAOYSA-N 0.000 description 10
- 239000004215 Carbon black (E152) Substances 0.000 description 8
- LCGLNKUTAGEVQW-UHFFFAOYSA-N dimethyl ether Chemical compound COC LCGLNKUTAGEVQW-UHFFFAOYSA-N 0.000 description 8
- 238000004821 distillation Methods 0.000 description 8
- 229960004337 hydroquinone Drugs 0.000 description 8
- IJGRMHOSHXDMSA-UHFFFAOYSA-N nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 8
- 239000007858 starting material Substances 0.000 description 8
- 238000007792 addition Methods 0.000 description 6
- 230000015572 biosynthetic process Effects 0.000 description 6
- 125000004432 carbon atoms Chemical group C* 0.000 description 6
- 238000005755 formation reaction Methods 0.000 description 6
- CTQNGGLPUBDAKN-UHFFFAOYSA-N o-xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 description 6
- -1 phenolic hydroxyl radicals Chemical class 0.000 description 6
- 238000002360 preparation method Methods 0.000 description 6
- 230000035484 reaction time Effects 0.000 description 6
- 239000000243 solution Substances 0.000 description 6
- QAOWNCQODCNURD-UHFFFAOYSA-L sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 6
- 239000008096 xylene Substances 0.000 description 6
- 239000011701 zinc Substances 0.000 description 6
- 229910052725 zinc Inorganic materials 0.000 description 6
- MRBKEAMVRSLQPH-UHFFFAOYSA-N 3-tert-butyl-4-hydroxyanisole Chemical class COC1=CC=C(O)C(C(C)(C)C)=C1 MRBKEAMVRSLQPH-UHFFFAOYSA-N 0.000 description 4
- 239000007864 aqueous solution Substances 0.000 description 4
- UHOVQNZJYSORNB-UHFFFAOYSA-N benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 4
- 239000006227 byproduct Substances 0.000 description 4
- 150000001983 dialkylethers Chemical class 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- VLKZOEOYAKHREP-UHFFFAOYSA-N hexane Chemical compound CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 description 4
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 4
- 229910052753 mercury Inorganic materials 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- 229910052757 nitrogen Inorganic materials 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- MYMOFIZGZYHOMD-UHFFFAOYSA-N oxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 4
- 229910052760 oxygen Inorganic materials 0.000 description 4
- 150000002989 phenols Chemical class 0.000 description 4
- KWYUFKZDYYNOTN-UHFFFAOYSA-M potassium hydroxide Inorganic materials [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 4
- 239000004250 tert-Butylhydroquinone Substances 0.000 description 4
- 235000019281 tert-butylhydroquinone Nutrition 0.000 description 4
- VFWCMGCRMGJXDK-UHFFFAOYSA-N 1-Chlorobutane Chemical group CCCCCl VFWCMGCRMGJXDK-UHFFFAOYSA-N 0.000 description 2
- RDOXTESZEPMUJZ-UHFFFAOYSA-N Anisole Chemical compound COC1=CC=CC=C1 RDOXTESZEPMUJZ-UHFFFAOYSA-N 0.000 description 2
- NEHMKBQYUWJMIP-UHFFFAOYSA-N Chloromethane Chemical compound ClC NEHMKBQYUWJMIP-UHFFFAOYSA-N 0.000 description 2
- DENRZWYUOJLTMF-UHFFFAOYSA-N Diethyl sulfate Chemical compound CCOS(=O)(=O)OCC DENRZWYUOJLTMF-UHFFFAOYSA-N 0.000 description 2
- ULYZAYCEDJDHCC-UHFFFAOYSA-N Isopropyl chloride Chemical compound CC(C)Cl ULYZAYCEDJDHCC-UHFFFAOYSA-N 0.000 description 2
- 241001527806 Iti Species 0.000 description 2
- 229940050176 Methyl Chloride Drugs 0.000 description 2
- TVMXDCGIABBOFY-UHFFFAOYSA-N Octane Chemical compound CCCCCCCC TVMXDCGIABBOFY-UHFFFAOYSA-N 0.000 description 2
- JVBXVOWTABLYPX-UHFFFAOYSA-L Sodium dithionite Chemical compound [Na+].[Na+].[O-]S(=O)S([O-])=O JVBXVOWTABLYPX-UHFFFAOYSA-L 0.000 description 2
- DQWPFSLDHJDLRL-UHFFFAOYSA-N Triethyl phosphate Chemical compound CCOP(=O)(OCC)OCC DQWPFSLDHJDLRL-UHFFFAOYSA-N 0.000 description 2
- WVLBCYQITXONBZ-UHFFFAOYSA-N Trimethyl phosphate Chemical compound COP(=O)(OC)OC WVLBCYQITXONBZ-UHFFFAOYSA-N 0.000 description 2
- 230000002378 acidificating Effects 0.000 description 2
- 125000001931 aliphatic group Chemical group 0.000 description 2
- 229910052783 alkali metal Inorganic materials 0.000 description 2
- 125000003545 alkoxy group Chemical group 0.000 description 2
- 150000001346 alkyl aryl ethers Chemical class 0.000 description 2
- 150000001348 alkyl chlorides Chemical class 0.000 description 2
- 125000000217 alkyl group Chemical group 0.000 description 2
- 125000003118 aryl group Chemical group 0.000 description 2
- 229940038926 butyl chloride Drugs 0.000 description 2
- 125000000484 butyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 2
- 239000003153 chemical reaction reagent Substances 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 238000010924 continuous production Methods 0.000 description 2
- MIHINWMALJZIBX-UHFFFAOYSA-N cyclohexa-2,4-dien-1-ol Chemical class OC1CC=CC=C1 MIHINWMALJZIBX-UHFFFAOYSA-N 0.000 description 2
- 230000002939 deleterious Effects 0.000 description 2
- 229940008406 diethyl sulfate Drugs 0.000 description 2
- 239000001307 helium Substances 0.000 description 2
- 229910052734 helium Inorganic materials 0.000 description 2
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium(0) Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 2
- 239000008079 hexane Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxyl anion Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 2
- 238000010348 incorporation Methods 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- UZKWTJUDCOPSNM-UHFFFAOYSA-N methoxybenzene Substances CCCCOC=C UZKWTJUDCOPSNM-UHFFFAOYSA-N 0.000 description 2
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 2
- 239000012022 methylating agents Substances 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 229910052754 neon Inorganic materials 0.000 description 2
- GKAOGPIIYCISHV-UHFFFAOYSA-N neon(0) Chemical compound [Ne] GKAOGPIIYCISHV-UHFFFAOYSA-N 0.000 description 2
- 239000012299 nitrogen atmosphere Substances 0.000 description 2
- OFBQJSOFQDEBGM-UHFFFAOYSA-N pentane Chemical compound CCCCC OFBQJSOFQDEBGM-UHFFFAOYSA-N 0.000 description 2
- 235000021317 phosphate Nutrition 0.000 description 2
- 230000003389 potentiating Effects 0.000 description 2
- 125000001436 propyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])[H] 0.000 description 2
- 239000003223 protective agent Substances 0.000 description 2
- 239000000376 reactant Substances 0.000 description 2
- 230000036647 reaction Effects 0.000 description 2
- 230000001603 reducing Effects 0.000 description 2
- CMXPERZAMAQXSF-UHFFFAOYSA-M sodium;1,4-bis(2-ethylhexoxy)-1,4-dioxobutane-2-sulfonate;1,8-dihydroxyanthracene-9,10-dione Chemical compound [Na+].O=C1C2=CC=CC(O)=C2C(=O)C2=C1C=CC=C2O.CCCCC(CC)COC(=O)CC(S([O-])(=O)=O)C(=O)OCC(CC)CCCC CMXPERZAMAQXSF-UHFFFAOYSA-M 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 2
- DKGAVHZHDRPRBM-UHFFFAOYSA-N t-BuOH Chemical compound CC(C)(C)O DKGAVHZHDRPRBM-UHFFFAOYSA-N 0.000 description 2
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C41/00—Preparation of ethers; Preparation of compounds having groups, groups or groups
- C07C41/01—Preparation of ethers
- C07C41/09—Preparation of ethers by dehydration of compounds containing hydroxy groups
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C39/00—Compounds having at least one hydroxy or O-metal group bound to a carbon atom of a six-membered aromatic ring
- C07C39/24—Halogenated derivatives
- C07C39/26—Halogenated derivatives monocyclic monohydroxylic containing halogen bound to ring carbon atoms
- C07C39/27—Halogenated derivatives monocyclic monohydroxylic containing halogen bound to ring carbon atoms all halogen atoms being bound to ring carbon atoms
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C43/00—Ethers; Compounds having groups, groups or groups
- C07C43/02—Ethers
- C07C43/20—Ethers having an ether-oxygen atom bound to a carbon atom of a six-membered aromatic ring
- C07C43/23—Ethers having an ether-oxygen atom bound to a carbon atom of a six-membered aromatic ring containing hydroxy or O-metal groups
Definitions
- This iinventionr relates to a process for preparin'g a sub'sramiallyuquantitive yieldwof Ia: mixture of moreithan about l two parts of a Z-tertiai-yhutyI- l-alkoxyphenol' to-- geth'er with one' part: of a; 3-terti-arybutyl 4 alkoxyphenol, which process comprises reacting at an e'levated ternperm '11 ture mono tenianybutyl iiydrdquinone rwith a dialkyl Sui-r.
- The'YOun -"et 'a'l application also "disclosesa process" for the" preparation of a mixture of a major proportion of Z-t'rtiarybutyl-A metho'Xyp'honol ancl a minor proportion of ""3-t'ertia'rybutyl t rriethoxypheiiol by reacting at an elevated tern perature"mono tertiarybutyl hydroquinone with Himeth aqueous alkaline "solution containing at leastabout 0.1
- Thetemperature at Whic'h'theprocess is conducted is: advantageously: tromabont 50to about C. More.
- theprefe'rred temperaturer'ange is from] about 75 to aboutl00" C.-in Which range satisfactory reactioii'bccurs' in a reasonable length of'time.” Still more advantageous'ly'the reaction is conducted under 'reflux conditions whichautoir'iatically 'governs' the temperatureofthe reaction dependingupon the nature of the reaction medium and the concentra'tio'n'of reactants and,
- a nitrogen atmosphere can be employed. Examples of other inert atmospheres which can be advantageously used include helium, neon, etc. However, no inert atmosphere need necessarily be employed.
- etherification reagents which can be advantageously employed in accordance with the process of this invention include dialkyl sulfates, e. g. diethyl sulfate, dimethyl sulfate, ditertiarybutyl sulfate, etc., alkyl acid sulfates, e. g. propyl acid sulfate, methyl acid sulfate, etc., alkyl chlorides, e. g. isopropyl chloride, methyl chloride, secondary butyl chloride, etc. or alkyl phosphates, e. g. trimethyl phosphate, triethyl phosphate etc.
- dialkyl sulfates e. g. diethyl sulfate, dimethyl sulfate, ditertiarybutyl sulfate, etc.
- alkyl acid sulfates e. g. propyl acid sulfate,
- the etherification agent is advantageously employed in at least a stoichiometrically equivalent quantity in proportion to the amount of tertiarybutyl hydroquinone employed as a starting material. It has been found that larger proportions (e. g. 1.5 stoichiometrical equivalents) of the etherification agent can also be advantageously employed although there is no purpose to be achieved by using more than about twice the quantity necessary to produce monoetherification. It has been found to be quite advantageous to employ about two thirds more of the etherification agent than is actually required on a stoichiometrical basis.
- the reaction is advantageously conducted in the pres ence of a protective material.
- the protective material consists of a finely divided or comminuted metal having reducing properties such as zinc or other equivalent metals.
- zinc other protective materials can be advantageously employed, e. g. Lykopon which consists essentially of sodium hydrosulfite (NazSzOr).
- zinc dust can be employed.
- Such a protective material is advantageously employed in minute quantities.
- zinc dust When zinc dust is employed, it has been found advantageous to use at least 0.1 percent or up to about 1% or more; generally from about A- to about /2 percent of zinc dust (based on the weight of the mono-tertiarybutyl hydroquinone) can be employed whereby deleterious by-products are substantially completely eliminated. If there is a trace of residual color in the crude reaction product, removal may be made complete by distillation in the presence of about 0.1 percent zinc dust. It is evident that other metallic dusts, other powdered alkali metal hydrosulfites, and other equivalent protective materials can be similarly employed.
- the non-aqueous liquid phase of the medium in which the reaction is conducted advantageously contains a solvent selected from the group consisting of aliphatic and aromatic hydrocarbons containing from about 5 to about carbon atoms.
- a solvent selected from the group consisting of aliphatic and aromatic hydrocarbons containing from about 5 to about carbon atoms.
- hydrocarbons include normal pentane, octane, hexane, heptane, benzene, toluene, xylene, mixtures of paraflinic hydrocarbons, straight-run naphthas and various mixtures and solvents of hydrocarbon nature derived from these materials.
- Other solvents can be similarly employed but those mentioned are generally most advantageously useful.
- a suflicient quantity of the solvent should be employed to substantially completely dissolve the mixed isomers of tertiarybutyl-4-alkoxyphenol in the reaction product. Generally speaking, about twice the weight of the mono-tertialybutyl hydroquinone of such a
- the amount of water employed in the aqueous liquid phase of the reaction medium is similarly subject to considerable wide variation within reasonable limits. As indicated by the examples set forth below, from 4 to 5 times the weight of the mono-tertiarybutyl hydroquinone of water can be advantageously employed. These examples illustrate amounts of water and solvent which can be used satisfactorily from a practical standpoint. Variations in the amounts of water and solvent, within reasonable limits, do not deleteriously effect the efficacy of the reaction process.
- An important factor in conducting the process of this invention lies in providing sutficient agitation to effect thorough mixing of whatever amounts of water and solvent are used. This can be accomplished by the stirring, shaking, maintaining reflux conditions, employing other suitable means, etc.
- the reaction mixture can be advantageously maintained in an alkaline condition during the course of the reaction by the incorporation of a caustic such as an alkali metal hydroxide, e. g. NaOH, KOH, etc.
- a caustic such as an alkali metal hydroxide, e. g. NaOH, KOH, etc.
- this alkaline condition is created by introducing a solution of an alkali metal hydroxide in water into the reaction mixture from time to time whereby especially high alkalinity is avoided. Undissolved caustic can also be added.
- caustic is provided in the reaction mixture so as to neutralize free acid released from the etherification agent. Too much alkalinity tends to increase the formation of the dialkyl ether of tertiarybutyl hydroquinone. Under the conditions of the reaction set forth in the examples given below, it is advantageous to limit the amount of caustic to about a 50% stoichiometrical excess of that needed to neutralize the free acid which might be formed based on the quantity of etherification agent employed, e. g. amounts in excess of 1.92 moles of caustic for each mole of dimethyl sulfate used in the examples below tended to increase the formation of dimethyl ether of mono-tertiarybutyl hydro quinone.
- the amount of caustic given in step-wise addition to the reaction mixture in order to give the most generally advantageous results.
- the caustic added in aqueous solution is purged with nitrogen to remove any oxygen.
- the factor of time in regard to the reaction is not critical and can be varied widely depending upon the reaction conditions.
- the working examples set forth below illustrate useful reaction periods under the reaction periods employed therein.
- reaction product can be separated and purified in various ways other than that illustrated by the examples which set forth an advantageous procedure found to be quite satisfactory in obtaining economical yields.
- the protective agent such as zinc dust, water and a hydrocarbon solvent.
- the reaction vessel can be advantageously equipped with means for agitation, a reflux condenser, a thermometer and a dropping funnel. It is advantageous to bring the charge in the reaction vessel to a reflux condition providing constant agitation. It is then advantageous to introduce an aqueous solution of a caustic, e. g. sodium hydroxide, into the reaction vessel at such a rate that refluxing is not stopped and the reaction is maintained under alkaline conditions.
- a caustic e. g. sodium hydroxide
- the total reaction time was 18 hours and the reaction temperature was 8283.5 C.
- the batch was acidified with the sulfuric acid, then the hot toluene layer was separated from the aqueous layer, washed with 100 cc. of hot water, and the solvent removed by distillation at 10 mm. mercury pressure. This dried, crude material was distilled at 10 mm. mercury pressure to give a product which contained 97% mono-tertiarybutyl-4-hydroxy anisole and 3% monotertiarybutyl hydroquinone dimethyl ether. This monotertiarybutyl hydroquinone dimethyl ether was removed from the product as a low-boiler in the distillation.
- the process can be altered so as to result in the continuous etherification of mono-tertiarybutyl hydroquinone which can be introduced into the reaction zone over an extended period of time along with the introduction of the etherification agent; in such a process a portion of the non-aqueous liquid phase would be removed either continuously or from time to time after the reaction conditions had been maintained for a suitable period of time.
- the conditions described hereinabove would be maintained by suitable addition of water, solvent, etc. as may be required from time to time.
- alkali metal hydroxide is sodium hydroxide and the hydrocarbon is toluene.
Description
United States Patent "ice? MONOETHERIFICATION F MONO-TERTIARY USING A -HYDR O-.-m CARBON SOLVENT Milfoii of 'Newtalersey No Drawing. Application April 23, 1953',
Serial'Nd.350763"' 2 Glaiinst 1 c1; 260*61-3) This iinventionr relates to a process for preparin'g a sub'sramiallyuquantitive yieldwof Ia: mixture of moreithan about l two parts of a Z-tertiai-yhutyI- l-alkoxyphenol' to-- geth'er with one' part: of a; 3-terti-arybutyl 4 alkoxyphenol, which process comprises reacting at an e'levated ternperm '11 ture mono tenianybutyl iiydrdquinone rwith a dialkyl Sui-r.
compriaing -a non-aqueous liquid phase containing a hydroearbon solvent or any I other f inert water-immisciblephase maintained I in an alkaline condition during the course -of the; reaction." 1
One procedure-nowbeing-usedfor the preparationof the 't'wo isoniers of ter-tiarybutyl-4 alkoiiyphen01sinvolves the reaetion" of hydroq-uinone with 3 a methylating agent to "obtain 4-nietl'ioiiyphenohfollovved by alkylatioNof-the lat'ter 'witlr a source of the 'tertiat'ybutyl"radieal' s'uch as E isobut'ylene"*or tertiarybutyl alcohol? This process and the inheren'tdisadvantages involved are discussed-in a copendin'g application Serial" N01 277, 508; filed on March 19f195-2fby Young et a-Lfentitled Preparation of-Ter In -the"Yoiing'et al application a' new proces'sis disclosed" for the preparation of tertiarybutyl hydroquinoneem ploying 'an aromatichydrocarbon'solvent to facilitate the reaction whereby i the i end product consists substantially of "the mono-tertiarybutylderivative. The'YOun -"et 'a'l application also "disclosesa process" for the" preparation of a mixture of a major proportion of Z-t'rtiarybutyl-A metho'Xyp'honol ancl a minor proportion of ""3-t'ertia'rybutyl t rriethoxypheiiol by reacting at an elevated tern perature"mono tertiarybutyl hydroquinone with Himeth aqueous alkaline "solution containing at leastabout 0.1
percent of comminuted' zinc under an inert atmosphere; The*processdisclosed'by Young'et' a1 represented'a' major advarice. over "thepriori art; however, as "indicated in Example -o in the'Ymin'g et al.application,"the'product" obtained representedonly .about a percent conversion of n'ionoqertiarybutyl hydroquinoneto mono-tertiarybu tyl' 4-liydro'xy' 'anisole "of "the "following composition:
Pei-cent 3-tertiarybut yl= -hydroxyr anisoleuz-uua 79.4 2-te'rtiarybutyl 4 hydroxyaanisole; 17.6
Of the imon'o tetriarybutyl" hyclrdquinone" employed "by" Young et al in their Example 6 as a startingmate'ria'li thei'ejremained' in the reaction'product 236 ercent which'hati' not entered into"the .reactionfin addition; a
little over one'percent'of the starting material was converted to the dimethyl ether .of mono tertiarybutylhy drdquinone:
Although theYoiinget a1 process represents a substantial improvementovertheprior art-processyit is obvious ly morepracticaland'econoniiczfl from an =operat1o'nal standpoint to make use of substantially 'all of the monotertiarybut yl hydroquinone employed' as the starting materials In 'order f to do' s'o'by the process disclosed by Young et al it would-be necessary to either (1) recover the unreacted material from the reactionl product and! empl'oy it in a-'subsequent reaction or (2) employ much larger amounts of the ether ification agent in which: event the reaction product would *contain much larger -amounts-i r of the undesirable; 'dimethyl ether of the mono-tertiary-b butyl Hydroquinonem As a'n unexpected improvementover the'Young-et a1 process and" as a clearly marked advanced over theprior art discussed in the young et-alapplicatiom fl-havenow found that byusin'g a' solvent g such -as an-aliphatioor 1 aromati'c ihydrocarbongin l association with the aqueous ethe'rifi'cationi medium-of Youn'g' et ali thatagreatly improved yield of the desired mono-teriarybutyl 4 a1koxy phenols -"resultsi 5 1 1 Moreover; the reaction product contains'*-a- -clearly predoniin'ant proportion of the more potent antioxidaiiflisomer 2-tertiarybutyl l-alkoxyphenol, with acorresponding reductien 'in the fori'nation of-the' undesirable dialkyl ether of nio'no 'ter'iarybutyl hydroquii nOneH 'Fu'ItI'l'eimOre, the' mono-tertiarybutyl hydroqui nonsta-rting rnaterial is substantially completely convert'eci-t'c$ for'rn th monoethrsi Arr-objectofthisinvention is to -provide a process for etheri'fying'*mono tertiarybutyl-hydroquinone whereby a substantially*quantitive yield-of monoalkyl ethers is produ'ced; "An additional object orrny invention is to pro videsuch-a process" wherein the ratio of '2-tert-iar'ybutyl 4 -"-aIkoxyphe1io1s-'to 3--' tertiarybutyl 4 --alkox'y'phenols is greater-tha'ri'tivoto one; Another-objectis to provide a processwhih substantially eliminates the necessity for recoveringwnuseti starting material from the reaction mixture thereby greatly"*itnproving the economical andoperational aspects-*of the preparation-of desirable anti- I oxidantsl In "broa'dfi'ern'ismyfinvention-provides a process for I preparinga' substantiallyquantitive yield of 'a mixture of a protective materiarina medium comprising a nonaqueous liquidipha's'e containing "a' solvent "selected from the"g roup consistingot aliphatic and aromatic hydrocarboiis containi'ng ifrorrr'aboufS to about 10 carbon atomsandah'a ueous liquid phase maintained in an alka-l line-"condition dur'ingthe' course' of the reaction.
Thetemperature at Whic'h'theprocess is conducted is: advantageously: tromabont 50to about C. More.
advantageously, theprefe'rred temperaturer'ange is from] about 75 to aboutl00" C.-in Which range satisfactory reactioii'bccurs' in a reasonable length of'time." Still more advantageous'ly'the reaction is conducted under 'reflux conditions whichautoir'iatically 'governs' the temperatureofthe reaction dependingupon the nature of the reaction medium and the concentra'tio'n'of reactants and,
reaction products thereinJThere is nothing critical about'thetemperature employed. Moreover,-the reac-- tion can beconductedunder-pressure if so desiredyit is. generally advantageously :carried'oubat atmospheric pressurew Elevated pressures-can-be employedif high reaction temperatures are" desired in connection with =the given solven 111 conducting-the reaction: anatmos'phere s Patented Jan. 1, 1957 can advantageously be employed whereby there will be insuflicient oxygen to substantially oxidize the phenolic hydroxyl radicals so as to avoid any undesirable formation of by-products. Advantageously, a nitrogen atmosphere can be employed. Examples of other inert atmospheres which can be advantageously used include helium, neon, etc. However, no inert atmosphere need necessarily be employed.
Examples of etherification reagents which can be advantageously employed in accordance with the process of this invention include dialkyl sulfates, e. g. diethyl sulfate, dimethyl sulfate, ditertiarybutyl sulfate, etc., alkyl acid sulfates, e. g. propyl acid sulfate, methyl acid sulfate, etc., alkyl chlorides, e. g. isopropyl chloride, methyl chloride, secondary butyl chloride, etc. or alkyl phosphates, e. g. trimethyl phosphate, triethyl phosphate etc. Other compounds which can be advantageously employed in conducting the etherification are readily apparent. An especially advantageous etherification agent is dimethyl sulfate.
In order to produce substantially quantitive yields in accordance with the process described above, the etherification agent is advantageously employed in at least a stoichiometrically equivalent quantity in proportion to the amount of tertiarybutyl hydroquinone employed as a starting material. It has been found that larger proportions (e. g. 1.5 stoichiometrical equivalents) of the etherification agent can also be advantageously employed although there is no purpose to be achieved by using more than about twice the quantity necessary to produce monoetherification. It has been found to be quite advantageous to employ about two thirds more of the etherification agent than is actually required on a stoichiometrical basis.
The reaction is advantageously conducted in the pres ence of a protective material. Most advantageously, the protective material consists of a finely divided or comminuted metal having reducing properties such as zinc or other equivalent metals. In place of zinc other protective materials can be advantageously employed, e. g. Lykopon which consists essentially of sodium hydrosulfite (NazSzOr). Most advantageously zinc dust can be employed. Such a protective material is advantageously employed in minute quantities. When zinc dust is employed, it has been found advantageous to use at least 0.1 percent or up to about 1% or more; generally from about A- to about /2 percent of zinc dust (based on the weight of the mono-tertiarybutyl hydroquinone) can be employed whereby deleterious by-products are substantially completely eliminated. If there is a trace of residual color in the crude reaction product, removal may be made complete by distillation in the presence of about 0.1 percent zinc dust. It is evident that other metallic dusts, other powdered alkali metal hydrosulfites, and other equivalent protective materials can be similarly employed.
The non-aqueous liquid phase of the medium in which the reaction is conducted advantageously contains a solvent selected from the group consisting of aliphatic and aromatic hydrocarbons containing from about 5 to about carbon atoms. Examples of such hydrocarbons include normal pentane, octane, hexane, heptane, benzene, toluene, xylene, mixtures of paraflinic hydrocarbons, straight-run naphthas and various mixtures and solvents of hydrocarbon nature derived from these materials. Other solvents can be similarly employed but those mentioned are generally most advantageously useful. A suflicient quantity of the solvent should be employed to substantially completely dissolve the mixed isomers of tertiarybutyl-4-alkoxyphenol in the reaction product. Generally speaking, about twice the weight of the mono-tertialybutyl hydroquinone of such a solvent can be advantageously employed. Considerable variation in the amount of solvent is obviously permissible.
The amount of water employed in the aqueous liquid phase of the reaction medium is similarly subject to considerable wide variation within reasonable limits. As indicated by the examples set forth below, from 4 to 5 times the weight of the mono-tertiarybutyl hydroquinone of water can be advantageously employed. These examples illustrate amounts of water and solvent which can be used satisfactorily from a practical standpoint. Variations in the amounts of water and solvent, within reasonable limits, do not deleteriously effect the efficacy of the reaction process. An important factor in conducting the process of this invention lies in providing sutficient agitation to effect thorough mixing of whatever amounts of water and solvent are used. This can be accomplished by the stirring, shaking, maintaining reflux conditions, employing other suitable means, etc.
The reaction mixture can be advantageously maintained in an alkaline condition during the course of the reaction by the incorporation of a caustic such as an alkali metal hydroxide, e. g. NaOH, KOH, etc. Advantageously, this alkaline condition is created by introducing a solution of an alkali metal hydroxide in water into the reaction mixture from time to time whereby especially high alkalinity is avoided. Undissolved caustic can also be added. By maintaining the reaction mixture in an alkaline condition, the acid resulting from the etherification reaction is neutralized. The reaction mixture is not allowed to become acidic until after the reaction has been completed.
Advantageously, enough caustic is provided in the reaction mixture so as to neutralize free acid released from the etherification agent. Too much alkalinity tends to increase the formation of the dialkyl ether of tertiarybutyl hydroquinone. Under the conditions of the reaction set forth in the examples given below, it is advantageous to limit the amount of caustic to about a 50% stoichiometrical excess of that needed to neutralize the free acid which might be formed based on the quantity of etherification agent employed, e. g. amounts in excess of 1.92 moles of caustic for each mole of dimethyl sulfate used in the examples below tended to increase the formation of dimethyl ether of mono-tertiarybutyl hydro quinone. As indicated under the reaction conditions set up in the examples, it is preferred to use the amount of caustic given in step-wise addition to the reaction mixture in order to give the most generally advantageous results. Advantageously the caustic added in aqueous solution is purged with nitrogen to remove any oxygen.
The factor of time in regard to the reaction is not critical and can be varied widely depending upon the reaction conditions. The working examples set forth below illustrate useful reaction periods under the reaction periods employed therein.
The reaction product can be separated and purified in various ways other than that illustrated by the examples which set forth an advantageous procedure found to be quite satisfactory in obtaining economical yields.
In conducting the process of this invention, it is advantageous to charge into a reaction vessel mono-tertiarybutyl hydroquinone, the protective agent such as zinc dust, water and a hydrocarbon solvent. The reaction vessel can be advantageously equipped with means for agitation, a reflux condenser, a thermometer and a dropping funnel. It is advantageous to bring the charge in the reaction vessel to a reflux condition providing constant agitation. It is then advantageous to introduce an aqueous solution of a caustic, e. g. sodium hydroxide, into the reaction vessel at such a rate that refluxing is not stopped and the reaction is maintained under alkaline conditions. After the initial introduction of the caustic, the etherification agent can be advantageously introduced over an extended period, e. g., one-half hour (longer or shorter periods can obviously be employed). During the course of the introduction of the etherification agent more caustic can be added, or additional caustic can be introduced after the etherification agent has been added. The reflux conditions are advantageously maintained with continued [agitation for the remainder of the reaction period which is generally of several hours duration. Upon a completion EXAMPLE 1 Materials Monotertiarybutylhydroquinone 830 gms. (0.5 mole). Toluene 250 cc. Dimethyl sulfate 52.5 gms. (0.416 mole). Sodium hydroxide 32.0 gms. (0.8 mole). Water 384 cc. Conc. sulfuric acid 4 cc. Zinc dust 0.5 gm.
Procedure The mono-tertiarybutyl hydroquinone, zinc dust, toluene and 284 cc. of the water were charged to a one liter, 3-necked, round bottom flask and the mixture heated to reflux, with agitation, and refluxed for -15 minutes. Next, a nitrogen purged solution of 21.3 gms. of the sodium hydroxide in 100 cc. of the water was run into the refluxing mixture in 10-15 minutes; then the dimethyl sulfate was added in 30 minutes. One hour after the first of the dimethyl sulfate was added, 10.7 gms. of the sodiurn hydroxide was added to the reaction mixture which was then refluxed 17 hours longer with agitation. The total reaction time was 18 hours and the reaction temperature was 8283.5 C. At the end of the reaction period, the batch was acidified with the sulfuric acid, then the hot toluene layer was separated from the aqueous layer, washed with 100 cc. of hot water, and the solvent removed by distillation at 10 mm. mercury pressure. This dried, crude material was distilled at 10 mm. mercury pressure to give a product which contained 97% mono-tertiarybutyl-4-hydroxy anisole and 3% monotertiarybutyl hydroquinone dimethyl ether. This monotertiarybutyl hydroquinone dimethyl ether was removed from the product as a low-boiler in the distillation.
Of the mono-tertiarybutyl hydroquinone charged as described in Example 1 above, 1.2% remained unreacted, 2.7% was converted to mono-tertiarybutyl hydroquinone dimethyl ether and 93.5% was converted to mono-tertiarybutyl-4-methoxyphenols of the following composition:
Percent 3 tertiarybutyl-4-methoxyphenol 28 2 tertiarybutyl-4-methoxyphenol 72 EXAMPLE 2 Materials Monotertiarybutyl hydroquinone 83.0 gms. (0.5 mole). n-Heptane 250 cc. Dimethyl sulfate 52.5 gms. (0.416 mole). Sodium hydroxide 32.0 gms. (0.8 mole). Water 384 cc. Cone. sulfuric acid 6.8 cc. Zinc dust 0.5 gm.
Procedure This experiment was run exactly like the one given in Example 1 except that n-heptane was used as the solvent, the total reaction time was 14.4 hours and the reaction temperature was 78.5-79 C. The material produced analyzed 92.0% mono-tertiarybutyl-4-methoxyphenol, 6.0% mono-tertiarybutyl hydroquinone dimethyl ether and 2% mono-tertiarybutyl hydroquinone. The conversion of monoetertiarybutyl hydroquinone; for: Example" 2 rani as follows:
87.5 mono-tertiarybutyl-4 rnethoxyphenols 5.3%- mono-tertiarybutyl hydroquinone. dimethyl ether 5.1% unreacted Isomeraratiotofproduct:
28% 3-tertiarybutyl-4-methoxyphenol 72% Z-tertiarybutyl-4-methoxyphenol EXAMPLE 3 Materials Monotertiarybutylhydroquinone 83.0 gms. (0.5 mole). Xylene 250 cc. Dimethyl sulfate 52.5 gms. (0.416 mole). Sodium hydroxide 32.0 gms. (0.8 mole). Water 384 cc. Cone. sulfuric acid 4 cc. Zinc dust 0.5 gm.
Procedure This experiment was run exactly like the one given in Example 1 except that xylene was used as the solvent, the total reaction time was 12.5 hours and the reaction temperature was 90.591.5 C. Also, instead of running under reflux during the reaction period volatile components were removed by slow distillation with replacement of the solvent as distilled. The material produced analyzed mono-tertiarybutyl-4-hydroxy anisole, 4.0% monotertiarybutyl hydroquinone dimethyl ether and 1% monotertiarybutyl hydroquinone. The conversion of monotertiarybutyl hydroquinone for the experiment ran as follows:
89.5% mono-tertiarybutyl-4-hydroxy anisole 3.5% mono-tertiarybutyl hydroquinone dimethyl ether 3.8% unreacted Isomer ratio of product:
28% 3-tertiarybutyl-4-methoxyphenol 72% 2-tertiarybutyl-4-methoxyphonol It is readily apparent that other solvents, other etherification agents and other variations in materials and the various conditions can be employed to obtain results similar to those exemplified by the preceding working examples. Moreover, the process employed can be modified as may be suitable for changes in the various conditions employed. The process can be altered so as to result in the continuous etherification of mono-tertiarybutyl hydroquinone which can be introduced into the reaction zone over an extended period of time along with the introduction of the etherification agent; in such a process a portion of the non-aqueous liquid phase would be removed either continuously or from time to time after the reaction conditions had been maintained for a suitable period of time. In operating according to the continuous process, the conditions described hereinabove would be maintained by suitable addition of water, solvent, etc. as may be required from time to time.
I claim:
1. In a process for oxy-alkylating a nuclearly monoalkylatecl dihydric phenol to form an alkoxy nuclearly monoalkylated monohydric phenol employing a dialkyl sulfate as the oxy-alkylating agent, which process is conducted under reflux conditions and under an inert atmosphere in the absence of an alkylating catalyst, the improvement which consists of oxy-alkylating mono-tertiary butylhydroquinone with a stoichiometric excess of a dialkyl sulfate having from 1 to 4 carbon atoms in each alkyl radical employing a two phase alkaline reaction medium consisting of (1) an aqueous liquid phase maintained in an alkaline condition during the course of the reaction by the introduction of an alkali metal hydroxide and (2) a non-aqueous liquid phase containing a hydrocarbon selected from the group consisting of aliphatic and aromatic hydrocarbons containing from 5 to 10 carbon atoms, whereby there is produced a substantially quantitative yield of a mixture of more than two parts of Z-tertiarybutyl-4-alkoxyphenol together with one part of 3-tertiarybutyl-4-alkoxypheno1.
2. The improvement in a process as defined in claim 1 wherein the oxy-alkylating agent is dimethyl sulfate, the
alkali metal hydroxide is sodium hydroxide and the hydrocarbon is toluene.
References Cited in the file of this patent UNITED STATES PATENTS
Claims (1)
1. IN A PROCESS FOR OXY-ALKYLATING A NUCLEARLY MONOALKYLATED DIHYDRIC PHENOL TO FORM AN ALKOXY NUCLEARLY MONOALKYLATED MONOHYDRIC PHENOL EMPLOYING A DIALKYL SULFATE AS THE OXY-ALKYLATING AGENT, WHICH PROCESS IS CONDUCTED UNDER REFLUX CONDITIONS AND UNDER AN INTER ATMOSPHERE IN THE ABSENCE OF AN ALKYLATING CATALYST, THE IMPROVEMENT WHICH CONSISTS OF OXY-ALKYLATING MONO-TERIARY BUTYLHYDROQUINONE WITH A STOICHIOMETRIC EXCESS OF A DIALKYL SULFATE HAVING FROM 1 TO 4 CARBON STOMS IN EACH ALKYL RADICAL EMPLOYING A TWO PHASE ALKALINE REACTION MEDIUM CONSISTING OF (1) AN AQUEOUS LIQUID PHASES MAINTAINED IN AN ALKALINE CONDITION DURING THE COURSE OF THE REACTION BY THE INTRODUCTION OF AN ALKALI METAL HYDROXIDE AND (2) A NON-AQUEOUS LIQUID PHASES CONTAINING AHYDROCARBON SELECTED FROM THE GROUP CONSISTING OF ALIPHATIC AND AROMATIC HYDROCARBONS CONTAINING FROM 5 TO 10 CARBON ATOMS, WHEREBY THERE IS PRODUCED A SUBSTANTIALLY QUANTITATIVE YIELD OF A MIXTURE OF MORE THAT TWO PARTS OF 2-TERTIARYBUTYL-4-ALKOXYPHENOL TOGETHER WITH ONE PART OF 3-TERTIARYBUTYL-4-ALKOXYPHENOL.
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| US2776321A true US2776321A (en) | 1957-01-01 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2887515A (en) * | 1959-05-19 | Preparation of tertiary butyl-x- | ||
| WO2007015260A2 (en) | 2005-04-19 | 2007-02-08 | Camlin Fine Chemicals Ltd. | Improvement in synthesis of butylated hydroxyanisole from tertiary butyl hydroquinone |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2470902A (en) * | 1946-09-28 | 1949-05-24 | Universal Oil Prod Co | Alkylation of phenols |
| US2722556A (en) * | 1952-03-19 | 1955-11-01 | Eastman Kodak Co | Preparation of tertiary butyl hydroquinone |
-
0
- US US2776321D patent/US2776321A/en not_active Expired - Lifetime
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2470902A (en) * | 1946-09-28 | 1949-05-24 | Universal Oil Prod Co | Alkylation of phenols |
| US2722556A (en) * | 1952-03-19 | 1955-11-01 | Eastman Kodak Co | Preparation of tertiary butyl hydroquinone |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2887515A (en) * | 1959-05-19 | Preparation of tertiary butyl-x- | ||
| WO2007015260A2 (en) | 2005-04-19 | 2007-02-08 | Camlin Fine Chemicals Ltd. | Improvement in synthesis of butylated hydroxyanisole from tertiary butyl hydroquinone |
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