CN101906107B - Method for synthesizing camphoricanhydride by alpha-pinene - Google Patents
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Abstract
The invention discloses a method for synthesizing camphoricanhydride by alpha-pinene, which comprises the following steps of: performing isomeric addition on the alpha-pinene and hydrogen chloride at the temperature of between -5 and 0 DEG C for 6 to 10 hours, filtering a reaction product to obtain a crude product 2-chlorobornane, and re-crystalizing to obtain refined 2-chlorobornane; performing dehydrochlorination on the 2-chlorobornane at the temperature of between 100 and 130 DEG C for 3 to 5 hours under the action of alkali to obtain norbornene; oxidizing the norbornene by using an oxidizing agent potassium permanganate in a solvent of acetic anhydride or an acetic anhydride-water mixture to obtain the camphoricanhydride, wherein the temperature of the oxidizing reaction is 35 to 40 DEG C and the reaction time is 4 to 6 hours; and adding a proper amount of ethyl acetate and saturated table salt solution into the reaction liquid, centrifuging to remove a byproduct MnO2, washing an organic layer by using saturated table salt solution, drying the organic layer by using Na2SO4, steaming to remove the solvent to obtain crude camphoricanhydride, and re-crystalizing by using absolute ethyl alcohol to obtain white crystals of camphoricanhydride. The method has the advantages of readily available raw materials, short synthetic route, good reaction selectivity, high product yield and the like.
Description
Technical field:
What the present invention relates to is a kind of method by α-Pai Xi SYNTHETIC CAMPHOR DAB 6 acid anhydrides.It is to be raw material with the α-Pai Xi, obtains bornyl chloride alkane with dry HCl addition, isomery, obtains bornylene through taking off HCl again, and bornylene obtains camphoric anhydride through oxidation.Belong to Minute Organic Synthesis and technical field of medicine synthesis.
Background technology:
Camphoric anhydride, chemistry is called 1,8,8-trimethylammonium-3-oxo dicyclo [3,2,1] suffering-2,4-diketone; 1,2,2-trimethylammonium-1,3-pentamethylene dicarboxylic anhydride; English camphoric anhydride by name; 1,8,8-trimethyl-3-oxabicyclo [3,2,1] octane-2,4-dione; 1,2,2-trimethyl-1,3-cyclopentanedicarbyxolic anhydride; Molecular formula is C
10H
14O
3, molecular weight is 182.21, and outward appearance is a white needle-like crystals, and fusing point is 222-225 ℃, is soluble in acetone and chloroform, dissolves in ETHYLE ACETATE, is slightly soluble in ether, is insoluble in ethanol, and water insoluble.Its chemical structure is as follows:
Camphoric anhydride
Camphoric anhydride is a kind of important monoterpenes compound, has important use in coating, chemical industry, medicine and other fields and is worth.Camphoric anhydride can be used for preparing water-soluble polymer, as amine trapping agent [US7521516]; Kim etc. [Microporous and mesoporous materials, 2008,116:227-232] successfully are used for camphoric anhydride the structure guiding agent of supersiliceous zeolite preparation; Reductibility pigment with the camphoric anhydride preparation can be used for fields [US7510765] such as paint, weaving, ink jet printing, makeup; Camphoric anhydride also can be used for synthetic drugs midbody Arylpiperidine derivatives [US5153206]; Bright etc. utilize camphoric anhydride successfully to synthesize the dicyclo imines as anxiety and antidepressant drug [US9242911], and its structure is as follows:
The chemical structure of anxiety and antidepressant drug
Preparing method about camphoric anhydride mainly contains camphor acid system, camphorquinone method, camphor method etc.Moloney etc. [Tetrahedron, Asymmetry, 1996,7 (9): 2551-2562] with (1R, 3S)-dextrocamphoric acid is a raw material, with CCl
4Make solvent, DMF makes catalyzer, dextrocamphoric acid and SOCl
2Reaction makes camphoric anhydride, and the yield of gained camphoric anhydride is 66%,
(c 5.13, CHCl
3).
Qian Huifen [Nanjing University of Technology's journal, 2004,26 (4): 35-39] is also with (1S; 3R)-and dextrocamphoric acid is a raw material SYNTHETIC CAMPHOR DAB 6 acid anhydrides, different is that dextrocamphoric acid and diacetyl oxide react 2h under reflux state, carries out crystallisation by cooling and recrystallization again and obtains camphoric anhydride; Efficiency of pcr product reaches 86%
(ρ=0.01g/ml, C
2H
5OH).
Equally with (1S; 3R)-dextrocamphoric acid makes raw material SYNTHETIC CAMPHOR DAB 6 acid anhydrides, [Tetrahedron:Asymmetry, 2010 such as Joel; 21:519-523] dextrocamphoric acid and methylsulfonyl chloride and triethylamine reaction are made camphoric anhydride; Efficiency of pcr product also reaches about 86%, and thick camphoric anhydride is that solvent carries out recrystallization purifying with ETHYLE ACETATE, the specific rotatory power of gained camphoric anhydride
(c 0.975, CHCl
3).
It is the method for feedstock production camphoric anhydride that Creary [J.Org.Chem.1980,45:2419-2425] has then reported for work with camphoryl silane alcohol ether.The employing methylene dichloride is a solvent, makes oxygenant oxidation camphoryl silane alcohol ether with ozone, but reaction needs carries out under-78 ℃, and yield is not high, only about 10%.
[Tetrahedron Lett., 1980,21:359-360] such as Japan scientist Okada is raw material with 3-diazo camphor then, adopts photosensitized oxidation to obtain camphoric anhydride, and yield is 38%.But this method products therefrom is the mixture of camphoric anhydride and camphorquinone, and the content of camphorquinone reaches 61%; The product purification separation difficulty, reaction preference is poor.
Suginome etc. [J.Chem.Soc.Perkin Trans.1,1990,1239] are then with periodate oxidation 3-oxycamphor SYNTHETIC CAMPHOR DAB 6 acid anhydrides, its yield only about 38%; Ji etc. [Synthetic communications, 2002,32 (11): 1659-1663] are raw material with the camphorquinone, obtain camphoric anhydride through photoxidation, reaction times 10h, and efficiency of pcr product reaches about 80%.
Jaroslav etc. [Journal of photochemistry and photobiology A:Chemistry, 2002,151:95-104] are solvent with acetate then, with H
2O
2For oxygenant oxidation camphorquinone prepares camphoric anhydride, the yield of camphoric anhydride is 68%.
Yang etc. [Arkansas academy of science proceedings, 197,97-99]] then to adopt camphor be raw material, prepares camphoric anhydride through steps such as hydroxyl metheneization, oxidations, not play-by-play efficiency of pcr product and opticity.
Bright etc. [US5242911,1993] report is a raw material SYNTHETIC CAMPHOR DAB 6 acid anhydrides with camphor.At first camphor and hydrazine reaction are generated the camphor hydrazone, with the Tosyl chloride reaction, generate the tolysulfonyl hydrazone again, generate bornylene with the lithium methide reaction again; With methyl alcohol is solvent, at-75 ℃ of following bornylenes through ozone oxidation, generate dialdehyde again under 75 ℃ through H
2O
2Oxidation obtains dextrocamphoric acid, and yield is 78%; Dextrocamphoric acid again with acetic anhydride, generate camphoric anhydride, yield is 97%.Reaction process is following:
Take a broad view of the existing literature report; The method of SYNTHETIC CAMPHOR DAB 6 acid anhydrides is a raw material with camphor or dextrocamphoric acid mainly at present; Have shortcomings such as few, the synthetic cost of raw material sources is high, operational path is long, exploring new synthetic route and compound method is one of research direction of SYNTHETIC CAMPHOR DAB 6 acid anhydrides.
Summary of the invention:
The present invention provides a kind of method by α-Pai Xi SYNTHETIC CAMPHOR DAB 6 acid anhydrides, and its synthetic route is following:
Its purpose is intended to simplify synthesis technique, the shortening synthetic route of camphoric anhydride, reduces production costs.
Technical solution of the present invention: a kind of method by α-Pai Xi SYNTHETIC CAMPHOR DAB 6 acid anhydrides; It is characterized in that adopting α-Pai Xi is raw material; Bornyl chloride alkane with hydrogen chloride gas addition, isomery obtain obtains bornylene through taking off HCl again, and bornylene obtains camphoric anhydride through potassium permanganate oxidation.
1) preparation of bornyl chloride alkane:
In the four-hole boiling flask that TM, whisking appliance, drying tube and hydrogen chloride tail gas absorption unit are housed, add α-Pai Xi; Use ice-salt bath to be cooled to system temperature and be about-5～0 ℃; Feed the exsiccant hydrogen chloride gas, reaction 6～10h, the gained reactant is through suction filtration; Remove a small amount of unreacted α-Pai Xi and excessive HCl, obtain solid crude product bornyl chloride alkane; Adopt absolute ethyl alcohol to carry out recrystallization, the quality-volume ratio of thick bornyl chloride alkane and absolute ethyl alcohol is 1: 8～10g/ml, obtains midbody bornyl chloride alkane.
2) preparation of bornylene:
In the four-hole boiling flask that TM, whisking appliance, reflux exchanger are housed, add bornyl chloride alkane, potassium tert.-butoxide or amylalcohol sodium and solvent N or methyl-sulphoxide; The mol ratio of bornyl chloride alkane and potassium tert.-butoxide or amylalcohol sodium is 1: 1～2, and bornyl chloride alkane is 1: 3～4g/ml with the mass/volume ratio of solvent N or methyl-sulphoxide; Heating makes temperature of reaction system rise to 100～130 ℃, and under this temperature, reacts 3～5h, after reactant is cooled to room temperature; Add excessive potassium tert.-butoxide of water decomposition or amylalcohol sodium; Using boiling range is 30～60 ℃ petroleum ether extraction 3 times, and combining extraction liquid also is washed with water to neutrality, through anhydrous Na
2SO
4Sherwood oil is removed in the distillation of dry back, obtains the white crystal bornylene.
3) preparation of camphoric anhydride:
Bornylene, diacetyl oxide, water adding are furnished with in three mouthfuls of round-bottomed flasks of TM and whisking appliance; Wherein the ratio of bornylene and diacetyl oxide and water is 1: 10～20: 0～10g/ml/ml; With ice bath reaction system is cooled to 0～5 ℃; Slowly add potassium permanganate, controlled temperature is in 10～40 ℃ of scopes, and the mol ratio of potassium permanganate and bornylene is 1: 2.5～3.0; After adding potassium permanganate, change heating in water bath, controlled temperature is at 35～40 ℃, and reaction 4～6h adopts GC to follow the tracks of to detect till do not have a raw material; Reaction solution is transferred in the Erlenmeyer flask, adds an amount of ETHYLE ACETATE and saturated aqueous common salt and stir 5min, after the centrifugal by product MnO that removes generation
2, with the layering of gained oil-water mixture, organic layer through the saturated common salt water washing to neutral, anhydrous Na
2SO
4Drying boils off solvent and obtains thick camphoric anhydride; After absolute ethyl alcohol carries out recrystallization, thick camphoric anhydride is 1: 8～9g/ml with the mass/volume ratio of absolute ethyl alcohol, obtains the camphoric anhydride white crystal.
Advantage of the present invention: utilize α-Pai Xi to be the feedstock production camphoric anhydride, compare, have that raw material is easy to get, a synthetic route weak point, good reaction selectivity, efficiency of pcr product advantages of higher with existing compound method.
Embodiment
Embodiment 1:
In the 250ml there-necked flask that TM, whisking appliance, drying tube and HCl absorption unit are housed, add 50g (0.37mole) α-Pai Xi, be cooled to system temperature at-5～0 ℃ with ice-salt bath.Measure the 60ml concentrated hydrochloric acid and place the 250ml there-necked flask, splash into the 40ml vitriol oil, and will generate HCl gas through anhydrous chlorine CaCl with the constant voltage addition funnel
2Dry back feeds in the α-Pai Xi, and about reaction 8h, reaction solution is condensed into faint yellow transparent solid gradually, to no longer absorbing till the HCl gas.The gained reactant is removed a small amount of unreacted α-Pai Xi and excessive HCl through suction filtration, obtains bornyl chloride alkane solid crude product.With absolute ethyl alcohol (bullion: ethanol=1: 8～10g/ml) carry out recrystallization, obtain midbody bornyl chloride alkane 51.1g, fusing point is 129～131 ℃, 207～208 ℃ of boiling points.Through gas chromatographic analysis, bornyl chloride alkane content is 93.7%, also has 6.3% 2-chlorine fenchane simultaneously.
In the 250ml there-necked flask of TM, whisking appliance is housed; Add bornyl chloride alkane 30g (GC purity assay about 93%), 39.10g potassium tert.-butoxide (technical grade; GC purity assay about 87%) and 100ml DMF; Be heated to 120 ℃, about isothermal reaction 4h, till GC detects and reacts completely to bornyl chloride alkane.Reactant adds 100ml water after being cooled to room temperature, with 3 * 100ml sherwood oil (30～60 ℃ of boiling ranges) extraction, to neutral, organic layer is through anhydrous Na through water washing for extraction liquid
2SO
4Boil off solvent after the drying, obtain bullion bornylene 17.54g, (thick bornylene: ethanol=1: 5～6g/ml) carries out recrystallization with absolute ethyl alcohol; Obtain white crystal bornylene 15.12g; Through gas chromatographic analysis, product consists of bornylene 92.7%, 2-chlorine fenchane 7.3%.
2.0g bornylene, 30ml diacetyl oxide, the adding of 10ml water are furnished with in the 100ml there-necked flask of whisking appliance, TM and condensing surface; Be cooled to 0～5 ℃ with ice bath, add 5.80g potassium permanganate in batches, controlled temperature is in 10～40 ℃ of scopes; After waiting to add potassium permanganate; Change heating in water bath into, control reaction temperature is at 35～40 ℃ of following reaction 4～6h, adopts GC to follow the tracks of to detect till do not have a raw material.Reaction solution is transferred in the Erlenmeyer flask of 250ml, adds 50ml ETHYLE ACETATE, 70ml saturated aqueous common salt and stir 5min, through the centrifugal by product MnO that removes generation
2, gained filtrating branch vibration layer, organic layer is washed till neutrality through saturated aqueous common salt, anhydrous Na
2SO
4Drying boils off solvent and obtains the white crystal camphoric anhydride, and transformation efficiency is 98.5%.With absolute ethyl alcohol (thick camphoric anhydride: the recrystallization of ethanol=1: 8～9g/ml); (analysis condition is: 50 ℃ (2min) rises to 280 ℃ (10min) through the GC analysis; Heat-up rate is 10 ℃/min, and injection port and detector temperature are 280 ℃), camphoric anhydride purity is more than 99%.The GC-MS analytical results of camphoric anhydride is following: 138 (27, M
+-COO), 123 (20,138-CH
3), 110 (M
+-COO-CO), 95 (100), 83 (40), 69 (57), 55 (40); The IR analytical results of camphoric anhydride is (cm as follows
-1, the KBr pressed disc method): 1805 (s), 1761 (m), 1128 (m), 1042 (m), 995 (m), 982 (m), 943 (w), 567 (w).
Embodiment 2:
In the 250ml four-hole boiling flask that TM, whisking appliance and drying tube and HCl absorption unit are housed, add 50g (0.37mole) α-Pai Xi and 70ml Skellysolve A, at room temperature feed exsiccant HCl gas, reaction 8h.The gained reaction solution is used 10%NaHCO
3Solution washing is removed excessive HCl, and organic layer is through anhydrous Na
2SO
4After boiling off Skellysolve A under the drying, normal pressure, obtain solid crude product bornyl chloride alkane.Carry out recrystallization with small amount of ethanol, obtain midbody bornyl chloride alkane 25.3g.
25.2g (0.2mole) Pentyl alcohol potassium is dissolved among the 100ml DMF, is heated to 120 ℃, splash into bornyl chloride alkane-DMF solution (17.3g (0.1mole) bornyl chloride alkane is dissolved in 50mlDMF) with addition funnel; Under this temperature, react 4h; Reactant adds 100ml water after cooling, with 100ml sherwood oil (boiling range 30-60 ℃) extraction 3 times; Extraction liquid is washed with water to neutrality, through anhydrous Na
2SO
4The distillation of dry back removes desolvates, and obtains bornylene white crystal 10.8g.
Bornylene 2.0g (14.6mmole), 30ml acetate, water 6ml adding are furnished with in the 100ml there-necked flask of mechanical stirrer, TM and prolong, are cooled to 0-5 ℃ with ice bath, add 5.80g potassium permanganate (36.5mmole) in batches, this exothermic process is not obvious.Behind reinforced the finishing, change heating in water bath, controlled temperature is in 35～40 ℃ of scopes, and reaction 4～6h is transferred to reaction solution in the Erlenmeyer flask of 250ml, adds 50ml ETHYLE ACETATE, 70ml saturated aqueous common salt stirring 5min, after the centrifugal by product MnO that removes generation
2, gained filtrating branch vibration layer, the gained organic layer is washed till neutrality through saturated aqueous common salt, and organic layer is through anhydrous Na
2SO
4Drying boils off solvent and obtains the white crystal camphoric anhydride, and transformation efficiency is 70.5%.
Embodiment 3:
Bornylene 2.0g (14.6mmole), the adding of 30ml diacetyl oxide are furnished with in the 100ml there-necked flask of mechanical stirrer, TM and prolong; Be cooled to 0～5 ℃ with ice bath; Add 5.80g potassium permanganate (36.5mmole), this exothermic process is not obvious in batches, and temperature is easier to control.Potassium permanganate add finish after, change heating in water bath, control reaction temperature is in 35～40 ℃ of scopes; Behind reaction 4～6h; Reaction solution is transferred in the Erlenmeyer flask of 250ml, adds 50ml ETHYLE ACETATE, 70ml saturated aqueous common salt stirring 5min, after the centrifugal by product MnO that removes generation
2, gained filtrating branch vibration layer, the gained organic layer is washed till neutrality through saturated aqueous common salt, and organic layer is through anhydrous Na
2SO
4Drying boils off solvent and obtains the white crystal camphoric anhydride, and transformation efficiency is 94.2%.
In the above-described embodiments:
Among the bornylene preparation method, bornyl chloride alkane, organic bases and solvent add in the reaction flask simultaneously, and temperature of reaction is 100～130 ℃; Described organic bases is potassium tert.-butoxide or amylalcohol sodium; Described solvent is N or methyl-sulphoxide.
Among the bornylene preparation method, the mol ratio of bornyl chloride alkane and organic bases potassium tert.-butoxide or amylalcohol sodium is 1: 1～2mole/mole, and bornyl chloride alkane is 1: 3～4g/ml with the mass/volume ratio of solvent N or methyl-sulphoxide.
Adopt potassium permanganate to make oxygenant the bornylene oxidation is prepared camphoric anhydride; Solvent for use can be: acetate, diacetyl oxide, diacetyl oxide-water; Acetate-water equal solvent system; Wherein best is diacetyl oxide-water mixed solvent, and the ratio of bornylene-diacetyl oxide-water is 1: 10～20: 0～5g/ml/ml, and the mol ratio of potassium permanganate and bornylene is 1: 2.5～3.0.
Claims (1)
1. method by α-Pai Xi SYNTHETIC CAMPHOR DAB 6 acid anhydrides, it is characterized in that adopting α-Pai Xi is raw material, and the bornyl chloride alkane with hydrogen chloride gas addition, isomery obtain obtains bornylene through taking off HCl again, and bornylene obtains camphoric anhydride through potassium permanganate oxidation; The preparation technology of described bornyl chloride alkane is following:
In the four-hole boiling flask that TM, whisking appliance, drying tube and hydrogen chloride tail gas absorption unit are housed, add α-Pai Xi; Use ice-salt bath to be cooled to system temperature and be-5～0 ℃; Feed the exsiccant hydrogen chloride gas, reaction 6～10h, the gained reactant is through suction filtration; Remove a small amount of unreacted α-Pai Xi and excessive HCl, obtain solid crude product bornyl chloride alkane; Adopt absolute ethyl alcohol to carry out recrystallization, the quality-volume ratio of thick bornyl chloride alkane and absolute ethyl alcohol is 1: 8～10g/ml, obtains midbody bornyl chloride alkane; The preparation technology of described bornylene is following:
In the four-hole boiling flask that TM, whisking appliance, reflux exchanger are housed, add bornyl chloride alkane, strong organic bases and solvent, the mol ratio of bornyl chloride alkane and organic bases is 1: 1～2mole/mole, and bornyl chloride alkane and solvent quality/volume ratio are 1: 3～4g/ml; Heating makes temperature of reaction system rise to 100～130 ℃, and under this temperature, reacts 3～5h, after reactant is cooled to room temperature; Add the excessive organic bases of water decomposition; Using boiling range is 30～60 ℃ petroleum ether extraction 3 times, and combining extraction liquid also is washed with water to neutrality, through anhydrous Na
2SO
4Sherwood oil is removed in the distillation of dry back, obtains the white crystal bornylene; In the bornylene preparation method,
Bornyl chloride alkane, organic bases and solvent add in the reaction flask simultaneously, and temperature of reaction is 100～130 ℃; Described organic bases is a potassium tert.-butoxide; Described solvent is a N; In the bornylene preparation method, the mol ratio of bornyl chloride alkane and organic bases potassium tert.-butoxide is 1: 1～2mole/mole, and bornyl chloride alkane is 1: 3～4g/ml with the mass/volume ratio of solvent N; The synthesis technique of described camphoric anhydride is following:
Bornylene, diacetyl oxide, water adding are furnished with in three mouthfuls of round-bottomed flasks of TM and whisking appliance; Wherein the ratio of bornylene, diacetyl oxide and water is 1: 10～20: 0～10g/ml/ml; With ice bath reaction system is cooled to 0～5 ℃; Slowly add potassium permanganate, controlled temperature is in 10～40 ℃ of scopes, and the mol ratio of potassium permanganate and bornylene is 1: 2.5～3.0; After adding potassium permanganate, change heating in water bath, controlled temperature is at 35～40 ℃, and reaction 4～6h adopts GC to follow the tracks of to detect till do not have a raw material; Reaction solution is transferred in the Erlenmeyer flask, adds an amount of ETHYLE ACETATE and saturated aqueous common salt and stir 5min, after the centrifugal by product MnO that removes generation
2, with the layering of gained oil-water mixture, organic layer through the saturated common salt water washing to neutral, anhydrous Na
2SO
4Drying boils off solvent and obtains thick camphoric anhydride; After absolute ethyl alcohol carries out recrystallization, thick camphoric anhydride is 1: 8～9g/ml with the mass/volume ratio of absolute ethyl alcohol, obtains the camphoric anhydride white crystal.
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