CN115894540A - Preparation method of lithium tri-sec-butyl borohydride - Google Patents
Preparation method of lithium tri-sec-butyl borohydride Download PDFInfo
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- CN115894540A CN115894540A CN202211577000.9A CN202211577000A CN115894540A CN 115894540 A CN115894540 A CN 115894540A CN 202211577000 A CN202211577000 A CN 202211577000A CN 115894540 A CN115894540 A CN 115894540A
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- 238000002360 preparation method Methods 0.000 title claims abstract description 42
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 title claims abstract description 20
- 229910052744 lithium Inorganic materials 0.000 title claims abstract description 20
- -1 lithium aluminum hydride Chemical compound 0.000 claims abstract description 83
- IMNIMPAHZVJRPE-UHFFFAOYSA-N triethylenediamine Chemical compound C1CN2CCN1CC2 IMNIMPAHZVJRPE-UHFFFAOYSA-N 0.000 claims abstract description 52
- 150000001875 compounds Chemical class 0.000 claims abstract description 50
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims abstract description 49
- 239000003054 catalyst Substances 0.000 claims abstract description 31
- YUPAWYWJNZDARM-UHFFFAOYSA-N tri(butan-2-yl)borane Chemical compound CCC(C)B(C(C)CC)C(C)CC YUPAWYWJNZDARM-UHFFFAOYSA-N 0.000 claims abstract description 30
- 238000003756 stirring Methods 0.000 claims abstract description 22
- HLVFKOKELQSXIQ-UHFFFAOYSA-N 1-bromo-2-methylpropane Chemical compound CC(C)CBr HLVFKOKELQSXIQ-UHFFFAOYSA-N 0.000 claims abstract description 20
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 18
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N EtOH Substances CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 17
- 239000012280 lithium aluminium hydride Substances 0.000 claims abstract description 17
- WTEOIRVLGSZEPR-UHFFFAOYSA-N boron trifluoride Chemical compound FB(F)F WTEOIRVLGSZEPR-UHFFFAOYSA-N 0.000 claims abstract description 16
- 239000002904 solvent Substances 0.000 claims abstract description 15
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 9
- 229910015900 BF3 Inorganic materials 0.000 claims abstract description 8
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims abstract description 8
- 238000006243 chemical reaction Methods 0.000 claims abstract description 8
- 238000001914 filtration Methods 0.000 claims abstract description 6
- AEPKPAHKDYZWRU-UHFFFAOYSA-N lithium;tri(butan-2-yl)borane Chemical compound [Li].CCC(C)B(C(C)CC)C(C)CC AEPKPAHKDYZWRU-UHFFFAOYSA-N 0.000 claims abstract description 5
- 238000000034 method Methods 0.000 claims abstract description 5
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 claims description 48
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 claims description 24
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 claims description 9
- 235000011114 ammonium hydroxide Nutrition 0.000 claims description 9
- 238000010438 heat treatment Methods 0.000 claims description 9
- 239000007789 gas Substances 0.000 claims description 5
- 239000002994 raw material Substances 0.000 claims description 4
- 238000004821 distillation Methods 0.000 claims description 3
- 239000006228 supernatant Substances 0.000 abstract description 10
- 239000000126 substance Substances 0.000 abstract description 9
- 238000002156 mixing Methods 0.000 abstract description 5
- 239000000243 solution Substances 0.000 description 43
- 150000002240 furans Chemical class 0.000 description 28
- PXKLMJQFEQBVLD-UHFFFAOYSA-N bisphenol F Chemical compound C1=CC(O)=CC=C1CC1=CC=C(O)C=C1 PXKLMJQFEQBVLD-UHFFFAOYSA-N 0.000 description 12
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 description 9
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 description 9
- 239000000203 mixture Substances 0.000 description 9
- 238000005406 washing Methods 0.000 description 9
- LILXDMFJXYAKMK-UHFFFAOYSA-N 2-bromo-1,1-diethoxyethane Chemical compound CCOC(CBr)OCC LILXDMFJXYAKMK-UHFFFAOYSA-N 0.000 description 7
- 230000003197 catalytic effect Effects 0.000 description 6
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 description 6
- 238000010521 absorption reaction Methods 0.000 description 4
- 238000004440 column chromatography Methods 0.000 description 4
- 238000001816 cooling Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 239000011259 mixed solution Substances 0.000 description 4
- 239000002244 precipitate Substances 0.000 description 4
- WSLDOOZREJYCGB-UHFFFAOYSA-N 1,2-Dichloroethane Chemical compound ClCCCl WSLDOOZREJYCGB-UHFFFAOYSA-N 0.000 description 3
- 239000006227 byproduct Substances 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 3
- 238000002329 infrared spectrum Methods 0.000 description 3
- 229920000137 polyphosphoric acid Polymers 0.000 description 3
- 229910000027 potassium carbonate Inorganic materials 0.000 description 3
- 239000000376 reactant Substances 0.000 description 3
- 238000002390 rotary evaporation Methods 0.000 description 3
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 2
- 238000012512 characterization method Methods 0.000 description 2
- 239000003638 chemical reducing agent Substances 0.000 description 2
- 150000004678 hydrides Chemical class 0.000 description 2
- 150000002576 ketones Chemical class 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 239000012074 organic phase Substances 0.000 description 2
- 239000003208 petroleum Substances 0.000 description 2
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 description 2
- 238000010992 reflux Methods 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 238000000967 suction filtration Methods 0.000 description 2
- 239000010936 titanium Substances 0.000 description 2
- 229910052719 titanium Inorganic materials 0.000 description 2
- 238000005160 1H NMR spectroscopy Methods 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 238000005033 Fourier transform infrared spectroscopy Methods 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 238000005481 NMR spectroscopy Methods 0.000 description 1
- CZPWVGJYEJSRLH-UHFFFAOYSA-N Pyrimidine Chemical compound C1=CN=CN=C1 CZPWVGJYEJSRLH-UHFFFAOYSA-N 0.000 description 1
- 150000008360 acrylonitriles Chemical class 0.000 description 1
- AZDRQVAHHNSJOQ-UHFFFAOYSA-N alumane Chemical compound [AlH3] AZDRQVAHHNSJOQ-UHFFFAOYSA-N 0.000 description 1
- 125000003277 amino group Chemical group 0.000 description 1
- QGZKDVFQNNGYKY-UHFFFAOYSA-N ammonia Natural products N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 1
- XKMRRTOUMJRJIA-UHFFFAOYSA-N ammonia nh3 Chemical compound N.N XKMRRTOUMJRJIA-UHFFFAOYSA-N 0.000 description 1
- 239000003242 anti bacterial agent Substances 0.000 description 1
- 150000001728 carbonyl compounds Chemical class 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 150000005690 diesters Chemical class 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 150000002085 enols Chemical class 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000013067 intermediate product Substances 0.000 description 1
- 150000004694 iodide salts Chemical class 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 125000002950 monocyclic group Chemical group 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 125000001997 phenyl group Chemical group [H]C1=C([H])C([H])=C(*)C([H])=C1[H] 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
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- C07—ORGANIC CHEMISTRY
- C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
- C07F5/00—Compounds containing elements of Groups 3 or 13 of the Periodic Table
- C07F5/02—Boron compounds
- C07F5/027—Organoboranes and organoborohydrides
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- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
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- A01N55/00—Biocides, pest repellants or attractants, or plant growth regulators, containing organic compounds containing elements other than carbon, hydrogen, halogen, oxygen, nitrogen and sulfur
- A01N55/08—Biocides, pest repellants or attractants, or plant growth regulators, containing organic compounds containing elements other than carbon, hydrogen, halogen, oxygen, nitrogen and sulfur containing boron
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/55—Design of synthesis routes, e.g. reducing the use of auxiliary or protecting groups
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Abstract
The invention discloses a preparation method of lithium tri-sec-butyl borohydride; belongs to the field of inorganic chemical industry; the method comprises the following steps: mixing bromoisobutane with anhydrous ether to prepare bromoisobutane ether solution; adding magnesium powder, boron trifluoride and anhydrous ether into a container, uniformly stirring, slowly adding bromoisobutane ether solution, stirring for reaction, standing, taking supernatant, and distilling to obtain tri-sec-butylboron; dissolving tri-sec-butylboron in a solvent to obtain a tri-sec-butylboron solution, adding a catalyst, slowly adding a lithium aluminum hydride solution under the conditions of nitrogen protection and ice bath, uniformly stirring, and filtering to obtain a tri-sec-butylboron lithium solution; the catalyst comprises at least one of triethylene diamine and a novel diazacyclo compound; the novel diazacyclo compound is prepared from 2-amino-1-benzo [1,3] dioxo-5-ethanol; according to the preparation method, the lithium tri-sec-butylborohydride with higher yield can be obtained.
Description
Technical Field
The invention belongs to the field of inorganic chemical industry, and particularly relates to a preparation method of lithium tri-sec-butyl borohydride.
Background
Lithium tri-sec-butyl borohydride is a novel hydride reducing agent and has the characteristics of strong reducing capability and high regioselectivity and stereoselectivity. The lithium tri-sec-butyl borohydride tetrahydrofuran solution is a novel hydride reducing agent sold abroad, and has the advantages of high reducing capacity, strong regioselectivity and stereoselectivity and the like, and the reducing condition is very mild. The compound is used for asymmetric selective reduction of ketone to obtain alcohol, can also be used for 1,4 enol conjugate addition reduction to obtain ketone or alcohol, is used for selectively reducing conjugated double bonds and iodides of exocyclic acrylonitrile derivatives, is an effective meso-eliminating reagent in the opioid substitution N-non-opioid reaction of diester, dehalogenated monocyclic pyrimidine, rearranged 5-trimethylsilyl carbaldehyde and deprotected N-methoxycarbonyl, can effectively reduce conjugated carbonyl compounds under low temperature conditions, and has wide application in the field of antibacterial agents.
The prior art, for example, publication number CN 107446003A discloses a preparation method of lithium tri-sec-butylborohydride, which comprises the following steps: a step of preparing tri-sec-butylboron, a step of preparing reactants, and a step of preparing tri-sec-butylborohydride; and triethylene diamine is added in the preparation process and can be used for generating TED-AlH with aluminum hydride 3 The white precipitate was removed from the system to avoid the reaction proceeding to the second step, and lithium tri-sec-butylborohydride was obtained.
Disclosure of Invention
The invention aims to provide a preparation method of lithium tri-sec-butyl borohydride with high yield.
The technical scheme adopted by the invention for realizing the purpose is as follows:
a preparation method of lithium tri-sec-butyl borohydride comprises the following steps:
(1) Preparation of tri-sec-butylboron: placing bromoisobutane and anhydrous ether in a container, and uniformly stirring to obtain bromoisobutane ether solution; adding magnesium powder, boron trifluoride and anhydrous ether into a container, uniformly stirring, slowly adding the bromoisobutane ether solution, stirring for reaction, standing, taking supernatant, and distilling to obtain tri-sec-butylboron;
(2) Preparing lithium tri-sec-butyl borohydride: dissolving tri-sec-butylboron in a solvent to obtain a tri-sec-butylboron solution, adding a catalyst, slowly adding a lithium aluminum hydride solution under the conditions of nitrogen protection and ice bath, uniformly stirring, and filtering to obtain a tri-sec-butylborohydride lithium solution;
the catalyst in the step (2) comprises at least one of triethylene diamine and a novel diazacyclo compound;
the novel diazacyclo compound is prepared from 2-amino-1-benzo [1,3] dioxo-5-ethanol and ammonia water.
The invention adopts a novel diazacyclo compound as a catalyst for preparing the lithium tri-sec-butylborohydride, has certain catalytic activity, and can obtain the lithium tri-sec-butylborohydride with a certain yield.
In some embodiments of the present invention, in step (1), by weight, 20 to 40 parts of bromoisobutane, 550 to 750 parts of anhydrous ether, 3.5 to 7.5 parts of magnesium powder, and 6 to 12 parts of boron trifluoride are used.
It should be noted that, in some embodiments of the present invention, the catalyst includes triethylene diamine and a novel diazacyclo compound, wherein the weight ratio of the triethylene diamine to the novel diazacyclo compound is 1:0.5 to 1. Triethylene diamine and the novel diazacyclo compound are used together, and have specific proportion and content, so that the triethylene diamine and the novel diazacyclo compound have better catalytic activity, the generation of byproducts of reactants in a system can be avoided, and the lithium tri-sec-butyl borohydride with higher yield is obtained.
In some embodiments of the present invention, the standing time in step (1) is 8 to 14h.
It should be noted that, in some embodiments of the present invention, in step (1), the distillation step is: distilling at 35 to 45 ℃ for 4 to 8 hours, and then heating to 85 to 95 ℃ for distilling for 2 to 5 hours.
It should be noted that, in some embodiments of the present invention, in the step (2), the solvent includes tetrahydrofuran.
In some embodiments of the invention, in the step (2), by weight, 15 to 25 parts of tri-sec-butylboron, 75 to 150 parts of solvent, 8 to 15 parts of catalyst and 3 to 7 parts of lithium aluminum hydride are used.
It is noted that in some embodiments of the invention, the yield of lithium tri-sec-butylborohydride is greater than 84%.
In some embodiments of the present invention, the preparation method of the novel diazacyclo compound is: adding a catalyst into a reactor, heating to 350-450 ℃, adding 2-amino-1-benzo [1,3] dioxo-5-ethanol and ammonia water, and controlling the airspeed of the raw material gas to prepare the novel diazacyclo compound.
In some embodiments of the present invention, in the preparation method of the novel diazacyclo compound, the ratio of 2-amino-1-benzo [1,3] dioxo-5-ethanol to ammonia water is 1 to 5g:1mL.
It should be noted that in some embodiments of the present invention, in the preparation method of the novel diazacyclo compound, the catalyst is at least one of a titanium silicalite, a copper or nickel metal supported HZSM-5 catalyst; the adding amount of the catalyst is 25 to 50cm 3 。
In some embodiments of the invention, in the preparation method of the novel diazacyclo compound, the space velocity of the raw material gas is 0.25 to 4.5h -1 。
The invention adopts a novel diazacyclo compound as a catalyst for preparing lithium tri-sec-butylborohydride, and the novel diazacyclo compound has certain catalytic activity; triethylene diamine and the novel diazacyclo compound are used together, and have specific proportion and content, the triethylene diamine and the novel diazacyclo compound can have better catalytic activity, the generation of byproducts of reactants in a system can also be avoided, and then the lithium tri-sec-butyl borohydride with higher yield is obtained. Therefore, the invention provides a preparation method of lithium tri-sec-butyl borohydride with high yield.
Drawings
FIG. 1 is an IR spectrum of 2-amino-1-benzo [1,3] dioxo-5-ethanol and a novel diazacyclo compound of example 3;
FIG. 2 shows the furan derivatives of example 6 1 H nuclear magnetic resonance spectroscopy.
Detailed Description
The present invention is described in further detail below with reference to specific embodiments, which are given for the purpose of illustration only and are not intended to limit the scope of the invention. The examples provided below serve as a guide for further modifications by a person skilled in the art and do not constitute a limitation of the invention in any way.
It should be noted that in some embodiments of the present invention, the preparation process of tri-sec-butylboron is: putting 20 to 40 parts of bromoisobutane and 10 to 30 parts of anhydrous ether into a container, and uniformly stirring to prepare a bromoisobutane ether solution; adding 3.5 to 7.5 parts of magnesium powder, 6 to 12 parts of boron trifluoride and 520 to 720 parts of anhydrous ether into a three-neck flask, stirring uniformly, slowly dropwise adding the bromoisobutane ether solution, stirring for reaction for 2 to 4 hours, standing at room temperature for 8 to 14h, taking a supernatant, washing a precipitate after pouring out the supernatant by using the anhydrous ether, recovering a washing solution, combining the washing solution with the supernatant, distilling the supernatant at 35 to 45 ℃ for 4 to 8h, and then heating to 85 to 95 ℃ for 2 to 5h to obtain the tri-sec-butylboron.
It should be noted that, in some embodiments of the present invention, the preparation method of lithium tri-sec-butylborohydride is: dissolving 15 to 25 parts of tri-sec-butylboron in 75 to 150 parts of solvent to obtain a tri-sec-butylboron solution, adding 8 to 15 parts of catalyst, slowly adding a lithium aluminum hydride solution (3 to 7 parts of lithium aluminum hydride solution are dissolved in 20 to 70 parts of anhydrous ether) under the conditions of nitrogen protection and ice bath at 0 to 3 ℃, wherein the dropping time of the lithium aluminum hydride solution is 10 to 12h, stirring for 2 to 5h at 0 to 3 ℃ for uniformity, filtering to obtain a lithium tri-sec-butylborohydride solution, and distilling to obtain lithium tri-sec-butylborohydride.
In order to better protect the synthesized intermediate product, namely the tri-sec-butylboron, and further improve the yield of the tri-sec-butylborohydride lithium, the preferable measures adopted further comprise the following steps: adding a furan derivative into a solvent, wherein the molar ratio of the furan derivative to tetrahydrofuran is 0.25-0.55: 1, the furan derivative is combined with tetrahydrofuran to achieve better protection effect on tri-sec-butylboron so as to obtain the tri-sec-butylborohydride lithium with higher yield.
It should be noted that in some embodiments of the present invention, the furan derivatives are prepared from 4,4' -dihydroxydiphenylmethane and bromoacetaldehyde diethyl acetal.
It is further noted that in some embodiments of the present invention, the furan derivatives are prepared as follows:
dissolving 4,4' -dihydroxydiphenylmethane in dimethylformamide, adding potassium carbonate and bromoacetaldehyde diethyl acetal, uniformly mixing, heating to 80-95 ℃, reacting for 8-12h, cooling to room temperature, extracting with dichloromethane, collecting an organic phase, performing rotary evaporation, and performing column chromatography to obtain a substance a; dissolving the substance a in 1, 2-dichloroethane, adding polyphosphoric acid under the protection of nitrogen, uniformly mixing, refluxing for 18 to 24h at 80 to 95 ℃, cooling to room temperature, performing suction filtration, performing rotary evaporation, and performing column chromatography to obtain the furan derivative, wherein the yield is 12.8 to 16.5%.
It is further noted that, in some embodiments of the present invention, in the preparation method of the furan derivative, by weight, 4' -dihydroxydiphenylmethane is 1.5 to 4.5 parts, dimethylformamide is 35 to 60 parts, potassium carbonate is 4 to 10 parts, bromoacetaldehyde diethyl acetal is 3.7 to 8.5 parts, dichloromethane is 200 to 300 parts, substance a is 4 to 8 parts, 1, 2-dichloroethane is 15 to 45 parts, and polyphosphoric acid is 3 to 8 parts.
The technical scheme of the invention is further described in detail by combining the detailed description and the attached drawings:
example 1:
a preparation method of lithium tri-sec-butyl borohydride comprises the following steps:
(1) Preparing tri-sec-butylboron: according to the weight parts, 25 parts of bromoisobutane and 20 parts of anhydrous ether are placed in a container and uniformly stirred to prepare bromoisobutane ether solution; adding 4.5 parts of magnesium powder, 8.5 parts of boron trifluoride and 580 parts of anhydrous ether into a three-neck flask, uniformly stirring, slowly dropwise adding the bromoisobutane ether solution, stirring for reacting for 3 hours, standing for 12 hours at room temperature, taking supernate, washing the precipitate after pouring out the supernate with the anhydrous ether, recovering the washing liquid, combining the washing liquid with the supernate, distilling the supernate for 6 hours at 40 ℃, heating to 95 ℃ and distilling for 3 hours to obtain tri-sec-butylboron;
(2) Preparing lithium tri-sec-butylborohydride: dissolving 18 parts of tri-sec-butylboron in 100 parts of tetrahydrofuran to obtain a tetrahydrofuran solution of tri-sec-butylboron, adding 9.5 parts of triethylene diamine, slowly adding a lithium aluminum hydride solution (3.5 parts of the lithium aluminum hydride solution are dissolved in 30 parts of anhydrous ether) under the conditions of nitrogen protection and ice bath at 0 ℃, wherein the dropping time of the lithium aluminum hydride solution is 10 hours, stirring for 2 hours in the ice bath at 0 ℃ until the solution is uniform, filtering to obtain a lithium tri-sec-butylborohydride solution, and distilling to obtain the lithium tri-sec-butylboron.
Example 2:
a preparation method of lithium tri-sec-butylborohydride, which is different from the embodiment 1 in that: in the step (1), according to parts by weight, placing 30 parts of bromoisobutane and 30 parts of anhydrous ether in a container, and uniformly stirring to prepare a bromoisobutane ether solution; adding 6 parts of magnesium powder, 7.5 parts of boron trifluoride and 550 parts of anhydrous ether into a three-neck flask, uniformly stirring, slowly dropwise adding the bromoisobutane ether solution, stirring for reacting for 3 hours, standing at room temperature for 12 hours, taking a supernatant, washing a precipitate after the supernatant is poured out by using anhydrous ether, recovering a washing solution, combining the washing solution with the supernatant, distilling the supernatant for 5 hours at 45 ℃, heating to 95 ℃ and distilling for 4 hours to obtain the tri-sec-butylboron.
Example 3:
a preparation method of lithium tri-sec-butylborohydride, which is different from the embodiment 1 in that: in the step (2), the catalyst triethylene diamine is replaced by a novel diazacyclo compound.
Specifically, in this embodiment, the preparation method of the novel diazacyclo compound is as follows: adding 50cm into a fixed bed reactor 3 Titanium silicalite TS-1 (Purchased from Shandong Daqi chemical science and technology Co., ltd.), then heated to 385 ℃, and then 2-amino-1-benzo [1,3] is added]Dioxo-5-ethanol with aqueous ammonia, wherein 2-amino-1-benzo [1,3]]The proportion of the dioxo-5-ethanol to the ammonia water is 2.5g:1mL, and the space velocity of the raw material gas is controlled to be 1.5h -1 And analyzing by using an SP 6890 gas chromatograph (a chromatographic column is a quartz capillary column of SE-30, the column length is 30 m), and processing data by using a GC-2010 chromatographic workstation to prepare the novel diazacyclo compound.
Example 4:
a preparation method of lithium tri-sec-butyl borohydride, which is different from the embodiment 3 in that: in the step (2), 23 parts of tri-sec-butylboron is dissolved in 150 parts of tetrahydrofuran to obtain a tetrahydrofuran solution of tri-sec-butylboron, 8 parts of novel diazacyclo compound is added, under the conditions of nitrogen protection and ice bath at 0 ℃, a lithium aluminum hydride solution (5.5 parts of the lithium aluminum hydride solution are dissolved in 50 parts of anhydrous ether) is slowly added, wherein the dropping time of the lithium aluminum hydride solution is 10.5h, the mixture is stirred in the ice bath at 0 ℃ for 3h until the mixture is uniform, the mixture is filtered to obtain a lithium tri-sec-butylborohydride solution, and the lithium tri-sec-butylborohydride solution is obtained by distillation.
In this example, the preparation of the novel diazacyclo compound was the same as in example 3.
Example 5:
a preparation method of lithium tri-sec-butyl borohydride, which is different from the embodiment 1 in that: in the step (2), a catalyst triethylene diamine is replaced by a mixture of triethylene diamine and a diazacyclo compound, wherein the weight ratio of the triethylene diamine to the diazacyclo compound is 1:0.75.
in this example, the preparation of the diazacyclo compound was the same as in example 3.
Example 6:
a preparation method of lithium tri-sec-butyl borohydride, which is different from the embodiment 1 in that: in the step (2), 18 parts of tri-sec-butylboron is dissolved in 100 parts of mixed solution of furan derivatives and tetrahydrofuran, wherein the weight ratio of the furan derivatives to the tetrahydrofuran is 0.25:1, obtaining a tetrahydrofuran solution of tri-sec-butylboron, adding 9.5 parts of triethylene diamine, slowly adding a lithium aluminum hydride solution (3.5 parts of the lithium aluminum hydride solution in 30 parts of anhydrous ether) under the conditions of nitrogen protection and ice bath at 0 ℃, wherein the dropping time of the lithium aluminum hydride solution is 10 hours, stirring the solution for 2 hours in the ice bath at 0 ℃ until the solution is uniform, filtering the solution to obtain a tri-sec-butylboron lithium solution, and distilling the solution to obtain the tri-sec-butylboron lithium.
Specifically, in this example, the preparation method of the furan derivative is as follows:
dissolving 2.7 parts by weight of 4,4' -dihydroxydiphenylmethane in 45 parts by weight of dimethylformamide, adding 8 parts by weight of potassium carbonate and 2.5 parts by weight of bromoacetaldehyde diethyl acetal, uniformly mixing, heating to 85 ℃, reacting for 10 hours, cooling to room temperature, extracting for 2 times by using 250 parts of dichloromethane, collecting an organic phase, spin-drying the solvent, and performing pure petroleum ether column chromatography to obtain a substance a; dissolving 5.5 parts by weight of the substance a in 30 parts by weight of 1, 2-dichloroethane, adding 7 parts by weight of polyphosphoric acid under the protection of nitrogen, uniformly mixing, refluxing at 85 ℃ for 24 hours, cooling to room temperature, performing suction filtration to remove insoluble substances, performing rotary evaporation to remove the solvent, and performing pure petroleum ether column chromatography to obtain the furan derivative, wherein the yield is 13.5%. The structural formula is as follows:
。
example 7:
a preparation method of lithium tri-sec-butyl borohydride, which is different from the embodiment 6 in that: in the mixed solution of furan derivatives and tetrahydrofuran, the molar ratio of furan derivatives to tetrahydrofuran is 0.55:1.
in this example, the furan derivative was prepared in the same manner as in example 5.
Example 8:
a preparation method of lithium tri-sec-butyl borohydride, which is different from the embodiment 3 in that: in the step (2), 100 parts of tetrahydrofuran is replaced by 100 parts of a mixed solution of furan derivatives and tetrahydrofuran, wherein the molar ratio of the furan derivatives to the tetrahydrofuran is 0.25:1.
example 9:
a preparation method of lithium tri-sec-butylborohydride, which is different from the embodiment 5 in that: in the step (2), in the mixed solution of the furan derivative and tetrahydrofuran, the molar ratio of the furan derivative to tetrahydrofuran is 0.25:1.
example 10:
1. structural characterization of infrared spectrogram
The novel diazacyclo compound prepared in example 3 was infrared characterized using a Fourier transform infrared spectrometer (FTS-135 model).
FIG. 1 shows 2-amino-1-benzo [1,3] in example 3](ii) the infrared spectra of dioxo-5-ethanol and the novel diazacyclo compound; curves a, b are 2-amino-1-benzo [1,3] respectively](ii) an infrared spectrum of dioxo-5-ethanol with the novel diazacyclo compound; as can be seen from FIG. 1, 2-amino-1-benzo [1,3]]Dioxo-5-ethanol at 3360cm -1 The stretching vibration absorption peaks of the hydroxyl and the amino with stronger and wider widths appear on the left and the right; at 3010cm -1 The characteristic absorption peak appearing on the left and right sides is the stretching vibration of a benzene ring; relative to 2-amino-1-benzo [1,3]]Dioxo-5-ethanol, a novel diazacyclo compound at 3365cm -1 The characteristic absorption peaks of the left and right hydroxyl groups and amino groups are obviously weakened and are 1500cm -1 Characteristic absorption peaks of nitrogen-nitrogen single bonds appear on the left and right, which are probably that hydroxyl and amino are subjected to chemical reaction in the reaction process to form a novel diazacyclo compound; it is thus known to use 2-amino-1-benzo [1,3]]Dioxo-5-ethanol and ammonia water to obtain the novel diazacyclo compound.
2. Structural characterization of Compounds
The furan derivatives were tested using a Bruker DR X500 nuclear magnetic resonance apparatus (400 MHz).
1 H NHM（400MHz，CDCl 3 ）：7.81(d，2H，CH)、7.59(d，2H，CH)、7.25(d，2H，CH)、7.04(d，2H，CH)、6.78(d，2H，CH)、4.09(s，2H，CH 2 ) (ii) a Thus, the furan derivatives were obtained from 4,4' -dihydroxydiphenylmethane and bromoacetaldehyde diethyl acetal, and the hydrogen nuclear magnetic spectrum thereof is shown in fig. 2.
3. Yield of lithium tri-sec-butylborohydride
The yields of lithium tri-sec-butylborohydride obtained in examples 1-8 are shown in Table 1.
TABLE 1 results of yield test of lithium tri-sec-butylborohydride
It can be seen from table 1 that the yield of lithium tri-sec-butylborohydride in example 5 is higher than 92%, and the yield of lithium tri-sec-butylborohydride in comparative examples 1-5 and example 5 is much higher than examples 1-4, which illustrates that the novel diazacyclo compound prepared by using 2-amino-1-benzo [1,3] dioxo-5-ethanol and ammonia water and the novel diazacyclo compound and triethylene diamine are used together as a catalyst, so that the yield of lithium tri-sec-butylborohydride is significantly improved; the yield of lithium tri-sec-butylborohydride in examples 6 to 7 is higher than 84%, the yield of lithium tri-sec-butylborohydride in example 9 is higher than 97%, the yield of lithium tri-sec-butylborohydride in example 6 is higher than example 1, the yield of lithium tri-sec-butylborohydride in example 8 is higher than example 3, and the yield of lithium tri-sec-butylborohydride in example 9 is higher than example 5, which shows that the furan derivatives prepared by using 4,4' -dihydroxydiphenylmethane and bromoacetaldehyde diethyl acetal, and the furan derivatives and tetrahydrofuran are used together as a solvent, and the two can better avoid the generation of byproducts, thereby obtaining the high yield of lithium tri-sec-butylborohydride.
4. Effect of catalyst on lithium tri-sec-butylborohydride yield
1) In the step (2), the catalyst is a mixture of triethylene diamine and a novel diazacyclo compound, and when the weight ratio of the triethylene diamine to the novel diazacyclo compound is 0.75: when the catalyst was added in an amount of 6 parts, 8 parts, 10 parts, 12 parts, 15 parts, and 17 parts by weight in the process for producing lithium tri-sec-butylborohydride (the other steps were the same as in example 1), the amounts were designated as test example a, test example B, test example C, test example D, test example E, and test example F, respectively, and the yield of lithium tri-sec-butylborohydride was measured.
TABLE 2 yield of lithium tri-sec-butylborohydride
As can be seen from Table 2, the yield of lithium tri-sec-butylborohydride in the test examples B-E is 91.5%, and the yield of lithium tri-sec-butylborohydride in the comparative test examples A-F and the test examples B-E is higher than that of the test examples A and F, so that when the mixture of triethylene diamine and the novel diazacyclo compound is added as the catalyst in the preparation process of lithium tri-sec-butylborohydride, the catalyst has better catalytic activity and can obtain lithium tri-sec-butylborohydride with higher yield when the weight parts of the catalyst are 8 to 15 parts.
2) In the step (2), the catalyst is a mixture of triethylene diamine and a novel diazacyclo compound, and when the weight part of the catalyst is 9.5 parts, in the preparation process of lithium tri-sec-butylborohydride (other steps are the same as in example 1), the weight ratio of the triethylene diamine to the novel diazacyclo compound is respectively 1:0.25, 1:0.5, 1:0.75, 1:1. 1:1.25, and respectively marked as test 1, test 2, test 3, test 4 and test 5, and the yield of lithium tri-sec-butylborohydride is determined.
TABLE 3 yield of lithium tri-sec-butylborohydride
As can be seen from table 3, the yield of lithium tri-sec-butylborohydride in the test groups 2 to 4 is 91.7%, the yield of lithium tri-sec-butylborohydride in the test groups 2 to 4 is higher than that in the test groups 1 and 5 in the comparative test examples 1 to 5, which indicates that when a mixture of triethylene diamine and a novel diazacyclo compound is added as a catalyst during the preparation of lithium tri-sec-butylborohydride, the weight ratio of triethylene diamine to the novel diazacyclo compound is 1: when the concentration is 0.5 to 1, the catalyst has better catalytic activity, and lithium tri-sec-butylborohydride with higher yield can be obtained.
5. Effect of solvent on lithium tri-sec-Butylborohydride yield
In the step (1), when the prepared tri-sec-butylboron is dissolved in a solvent which is a mixture of furan derivatives and tetrahydrofuran, the molar ratio of the furan derivatives to the tetrahydrofuran is tested to be 0.15: 1. 0.25:1. 0.35: 1. 0.45: 1. 0.55:1. 0.65:1, and respectively marked as an experimental group K1, an experimental group K2, an experimental group K3, an experimental group K4, an experimental group K5, and an experimental group K6, and the yield of lithium tri-sec-butylborohydride was determined by using example 1 as a control group, wherein other preparation methods of lithium tri-sec-butylborohydride were the same as example 1.
TABLE 4 yield of lithium tri-sec-butylborohydride
As can be seen from table 4, the yield of lithium tri-sec-butylborohydride in experimental groups K2 to K5 is 85.5% higher than that in the control group, and the yield of lithium tri-sec-butylborohydride in experimental groups K2 to K5 is higher than that in experimental groups K1 and K6 in comparison with experimental groups K1 to K6, which indicates that in step (1) of preparing lithium tri-sec-butylborohydride, furan derivatives are prepared by using 4,4' -dihydroxydiphenylmethane and bromoacetaldehyde diethyl acetal, and the furan derivatives and tetrahydrofuran are used together as a solvent, and the molar ratio of the furan derivatives to tetrahydrofuran is 0.25 to 0.55:1, the lithium tri-sec-butylborohydride has better protection effect on tri-sec-butylborohydride so as to obtain lithium tri-sec-butylborohydride with higher yield and purity.
Conventional operations in the operation steps of the present invention are well known to those skilled in the art and will not be described herein.
The embodiments described above are intended to illustrate the technical solutions of the present invention in detail, and it should be understood that the above-mentioned embodiments are only specific embodiments of the present invention, and are not intended to limit the present invention, and any modification, supplement or similar substitution made within the scope of the principles of the present invention should be included in the protection scope of the present invention.
Claims (8)
1. A preparation method of lithium tri-sec-butyl borohydride comprises the following steps:
(1) Preparation of tri-sec-butylboron: placing bromoisobutane and anhydrous ether in a container, and uniformly stirring to obtain bromoisobutane ether solution; adding magnesium powder, boron trifluoride and anhydrous ether into a container, uniformly stirring, slowly adding the bromoisobutane ether solution, stirring for reaction, standing, taking supernate, and distilling to obtain tri-sec-butylboron;
(2) Preparing lithium tri-sec-butyl borohydride: dissolving tri-sec-butylboron in a solvent to obtain a tri-sec-butylboron solution, adding a catalyst, slowly adding a lithium aluminum hydride solution under the conditions of nitrogen protection and ice bath, uniformly stirring, and filtering to obtain a tri-sec-butylboron lithium solution;
the catalyst in the step (2) comprises at least one of triethylene diamine and a novel diazacyclo compound;
the novel diazacyclo compound is prepared from 2-amino-1-benzo [1,3] dioxo-5-ethanol and ammonia water.
2. The preparation method of lithium tri-sec-butylborohydride according to claim 1, which is characterized by comprising the following steps: in the step (1), the weight parts of bromoisobutane are 20 to 40 parts, the weight parts of anhydrous ether are 550 to 750 parts, the weight parts of magnesium powder are 3.5 to 7.5 parts, and the weight parts of boron trifluoride are 6 to 12 parts.
3. The preparation method of lithium tri-sec-butylborohydride according to claim 1, which is characterized by comprising the following steps: in the step (1), the distillation step is as follows: distilling at 35 to 45 ℃ for 4 to 8 hours, and then heating to 85 to 95 ℃ for distilling for 2 to 5 hours.
4. The preparation method of lithium tri-sec-butylborohydride according to claim 1, which is characterized by comprising the following steps: in the step (2), the solvent comprises tetrahydrofuran.
5. The method for preparing lithium tri-sec-butylborohydride according to claim 1, which comprises the following steps: in the step (2), by weight, 15 to 25 parts of tri-sec-butylboron, 75 to 150 parts of solvent, 8 to 15 parts of catalyst and 3 to 7 parts of lithium aluminum hydride.
6. The preparation method of lithium tri-sec-butylborohydride according to claim 1, which is characterized by comprising the following steps: the yield of lithium tri-sec-butylborohydride is higher than 84%.
7. The method for preparing lithium tri-sec-butylborohydride according to claim 1, which comprises the following steps: in the step (2), the catalyst comprises triethylene diamine and a novel diazacyclo compound, wherein the weight ratio of the triethylene diamine to the novel diazacyclo compound is 1:0.5 to 1.
8. The method for preparing lithium tri-sec-butylborohydride according to claim 1, which comprises the following steps: the preparation method of the novel diazacyclo compound comprises the following steps: adding a catalyst into a reactor, heating to 350-450 ℃, adding 2-amino-1-benzo [1,3] dioxo-5-ethanol and ammonia water, and controlling the airspeed of the raw material gas to prepare the novel diazacyclo compound.
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| CN106279227A (en) * | 2016-07-15 | 2017-01-04 | 车荣睿 | The preparation method of lithium triethylborohydride tetrahydrofuran solution |
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