CN102558209A - Bis(pinacolato)diboron production process - Google Patents

Abstract

The invention discloses a bis(pinacolato)diboron production process which is characterized in that boron trichloride is used as a raw material and is aminated with dimethylamine gas in an n-hexane system, the desalinated reaction solution and boron tribromide react at the room temperature, the prepared intermediate and magnesium are coupled in toluene, 1, 2-dichloroethane solution of pinacol is dropped into the desalinated reaction solution, and the target product is prepared via transesterification. The invention has the advantages that: n-hexane is used as a reaction solvent for the first two steps, the conversion rate of reaction is increased, and the ultra low temperature can be avoided; the safety of the process is improved due to use of magnesium; and the yield of the product is increased in transesterification through controlling the reaction temperature.

Description

Join boric acid pinacol ester production technique

Technical field

The present invention relates to join the production technique of boric acid pinacol ester.

Background technology

Joining boric acid pinacol ester, is a kind of medicine intermediate, its English another name: bis (pinacolato) diboron; Molecular formula is C12H24B2O4, and the production technique security of existing boric acid pinacol ester is not high, and reaction conversion ratio is low; Product yield is low, causes the wasting of resources.Therefore, should provide a kind of new technical scheme to address the above problem.

Summary of the invention

The objective of the invention is:, the production technique of the couplet boric acid pinacol ester that a kind of process safety is high, reaction conversion ratio is high, product yield is high is provided to above-mentioned deficiency.

For realizing above-mentioned purpose, the technical scheme that the present invention adopts is:

Join boric acid pinacol ester production technique, comprise the steps:

(1) will be equipped with earlier that to add 1900-2100 parts by volume mass concentrations in the four-hole bottle of mechanical stirring, TM, device for absorbing tail gas and prolong be 97-99% normal hexane; And stir, feed the boron trichloride gas of 180-210 mass parts, under 10-15 ℃, condition of normal pressure; Feed the n n dimetylaniline gas of 470-490 mass parts; Carry out amination reaction, suction filtration is removed the salt of separating out then, and filtrating joins in the four-hole bottle again;

(2) in above-mentioned filtrating, drip the boron tribromide of 210-230 mass parts in the time at 55-65min; Under the normal temperature and pressure, reaction 4.5-5.5h is after reaction is accomplished; On four-hole bottle, load onto rectifying volumn; At 68-70 ℃, distillation earlier obtains normal hexane under the condition of normal pressure, reduces pressure-0.09-0.1MPa again, is cooled to 60-65 ℃ and distills out midbody;

(3) get a four-hole bottle again; In four-hole bottle, add 2900-3100 parts by volume mass concentrations and be 97-99% toluene, the MAGNESIUM METAL 99 of 29-32 mass parts is divided put in the four-hole bottle for 3 times then, be warming up to 110-112 ℃ of backflows under the normal pressure; The midbody that obtains at last in the step (2) is added drop-wise in 30-60min in the four-hole bottle of this step; GC detects, and reduces temperature to 100-110 ℃, after the raw material complete reaction; Suction filtration desalination under protection of nitrogen gas, filtrating joins in this four-hole bottle again;

(4) with 290-310 mass parts tetramethyl ethylene ketone solution be dissolved in 480-520 parts by volume mass concentrations be 97-99% 1, in the 2-ethylene dichloride, in 50-65min, be added drop-wise to then in the employed four-hole bottle of step (3); Stir, normal pressure is warming up to 80-90 ℃ of backflows and carries out transesterification reaction, and the n n dimetylaniline gas of generation absorbs with 18-22% hydrochloric acid; GC monitoring raw material reaction is complete; Suction filtration obtains product, reclaims toluene and 1, the 2-ethylene dichloride after the filtrating rectifying.

Four above-mentioned steps, its reaction equation is following successively:

Advantage of the present invention is: select for use normal hexane as preceding two step reaction solvents, improved reaction conversion ratio, avoided utmost point coldcondition simultaneously; In the linked reaction of step (3), use MAGNESIUM METAL 99, the security that has improved technology.

Embodiment

Embodiment 1

Join boric acid pinacol ester production technique, comprise the steps:

(1) will be equipped with earlier that to add 1900 parts by volume mass concentrations in the four-hole bottle of mechanical stirring, TM, device for absorbing tail gas and prolong be 97% normal hexane; And stir, feed the boron trichloride gas of 180 mass parts, under 10 ℃, condition of normal pressure; Feed the n n dimetylaniline gas of 470 mass parts; Carry out amination reaction, suction filtration is removed the salt of separating out then, and filtrating joins in the four-hole bottle again;

(2) in 55min, in above-mentioned filtrating, drip the boron tribromide of 210 mass parts, under the normal temperature and pressure, reaction 4.5h; Reaction is loaded onto rectifying volumn, at 68 ℃ after accomplishing on four-hole bottle; Distillation earlier obtains normal hexane under the condition of normal pressure, reduces pressure-0.09MPa, is cooled to 60 ℃ again and distill out midbody;

(3) get a four-hole bottle again, adding 2900 parts by volume mass concentrations are 97% toluene in four-hole bottle, 29 parts of MAGNESIUM METAL 99s are divided put in the four-hole bottle for 3 times then; Be warming up to 110 ℃ of backflows under the normal pressure, the midbody that obtains at last in the step (2) is added drop-wise in 30min in the four-hole bottle of this step, GC detects; Reduce temperature to 100 ℃; After the raw material complete reaction, suction filtration desalination under protection of nitrogen gas, filtrating joins in this four-hole bottle again;

(4) with 290 mass parts tetramethyl ethylene ketone solution be dissolved in 480 parts by volume mass concentrations be 97% 1, in the 2-ethylene dichloride, in 50min, be added drop-wise to then in the employed four-hole bottle of step (3); Stir, normal pressure is warming up to 80 ℃ of backflows and carries out transesterification reaction, and the n n dimetylaniline gas of generation absorbs with 18% hydrochloric acid; GC monitoring raw material reaction is complete; Suction filtration obtains product, reclaims toluene and 1, the 2-ethylene dichloride after the filtrating rectifying.

Embodiment 2

Join boric acid pinacol ester production technique, comprise the steps:

(1) will be equipped with earlier that to add 2000 parts by volume mass concentrations in the four-hole bottle of mechanical stirring, TM, device for absorbing tail gas and prolong be 98% normal hexane; And stir, feed the boron trichloride gas of 200 mass parts, under 12 ℃, condition of normal pressure; Feed the n n dimetylaniline gas of 480 mass parts; Carry out amination reaction, suction filtration is removed the salt of separating out then, and filtrating joins in the four-hole bottle again;

(2) in above-mentioned filtrating, drip the boron tribromide of 220 mass parts in the time at 60min; Under the normal temperature and pressure, reaction 5h is after reaction is accomplished; On four-hole bottle, load onto rectifying volumn; At 69 ℃, distillation earlier obtains normal hexane under the condition of normal pressure, reduces pressure-0.095MPa, is cooled to 62 ℃ again and distill out midbody;

(3) get a four-hole bottle again, in four-hole bottle, add 3000 parts by volume mass concentrations and be 98% toluene, the MAGNESIUM METAL 99 of 30 mass parts is divided put in the four-hole bottle for 3 times then; Be warming up to 111 ℃ of backflows under the normal pressure, the midbody that obtains at last in the step (2) is added drop-wise in 45min in the four-hole bottle of this step, GC detects; Reduce temperature to 105 ℃; After the raw material complete reaction, suction filtration desalination under protection of nitrogen gas, filtrating joins in this four-hole bottle again;

(4) with 300 mass parts tetramethyl ethylene ketone solution be dissolved in 500 parts by volume mass concentrations be 98% 1, in the 2-ethylene dichloride, in 55min, be added drop-wise to then in the employed four-hole bottle of step (3); Stir, normal pressure is warming up to 85 ℃ of backflows and carries out transesterification reaction, and the n n dimetylaniline gas of generation absorbs with 20% hydrochloric acid; GC monitoring raw material reaction is complete; Suction filtration obtains product, reclaims toluene and 1, the 2-ethylene dichloride after the filtrating rectifying.

Embodiment 3

Join boric acid pinacol ester production technique, comprise the steps:

(1) will be equipped with earlier that to add 2100 parts by volume mass concentrations in the four-hole bottle of mechanical stirring, TM, device for absorbing tail gas and prolong be 99% normal hexane; And stir, feed the boron trichloride gas of 210 mass parts, under 15 ℃, condition of normal pressure; Feed the n n dimetylaniline gas of 490 mass parts; Carry out amination reaction, suction filtration is removed the salt of separating out then, and filtrating joins in the four-hole bottle again;

(2) in 65min, in above-mentioned filtrating, drip the boron tribromide of 230 mass parts, under the normal temperature and pressure, reaction 5.5h; Reaction is loaded onto rectifying volumn, at 70 ℃ after accomplishing on four-hole bottle; Distillation earlier obtains normal hexane under the condition of normal pressure, reduces pressure-0.1MPa, is cooled to 65 ℃ again and distill out midbody;

(3) get a four-hole bottle again, in four-hole bottle, add 3100 parts by volume mass concentrations and be 99% toluene, the MAGNESIUM METAL 99 of 32 mass parts is divided put in the four-hole bottle for 3 times then; Be warming up to 112 ℃ of backflows under the normal pressure, the midbody that obtains at last in the step (2) is added drop-wise in 60min in the four-hole bottle of this step, GC detects; Reduce temperature to 110 ℃; After the raw material complete reaction, suction filtration desalination under protection of nitrogen gas, filtrating joins in this four-hole bottle again;

(4) with 310 mass parts tetramethyl ethylene ketone solution be dissolved in 520 parts by volume mass concentrations be 99% 1, in the 2-ethylene dichloride, in 65min, be added drop-wise to then in the employed four-hole bottle of step 3; Stir, normal pressure is warming up to 90 ℃ of backflows and carries out transesterification reaction, and the n n dimetylaniline gas of generation absorbs with 22% hydrochloric acid; GC monitoring raw material reaction is complete; Suction filtration obtains product, reclaims toluene and 1, the 2-ethylene dichloride after the filtrating rectifying.

Claims (1)

1. join boric acid pinacol ester production technique, it is characterized in that, comprise the steps:

(1) will be equipped with earlier that to add 1900-2100 parts by volume mass concentrations in the four-hole bottle of mechanical stirring, TM, device for absorbing tail gas and prolong be 97-99% normal hexane; And stir, feed the boron trichloride gas of 180-210 mass parts, under 10-15 ℃, condition of normal pressure; Feed the n n dimetylaniline gas of 470-490 mass parts; Carry out amination reaction, suction filtration is removed the salt of separating out then, and filtrating joins in the four-hole bottle again;

(2) in above-mentioned filtrating, drip the boron tribromide of 210-230 mass parts in the time at 55-65min; Under the normal temperature and pressure, reaction 4.5-5.5h is after reaction is accomplished; On four-hole bottle, load onto rectifying volumn; At 68-70 ℃, distillation earlier obtains normal hexane under the condition of normal pressure, reduces pressure-0.09-0.1MPa again, is cooled to 60-65 ℃ and distills out midbody;

(3) get a four-hole bottle again; In four-hole bottle, add 2900-3100 parts by volume mass concentrations and be 97-99% toluene, the MAGNESIUM METAL 99 of 29-32 mass parts is divided put in the four-hole bottle for 3 times then, be warming up to 110-112 ℃ of backflows under the normal pressure; The midbody that obtains at last in the step (2) is added drop-wise in 30-60min in the four-hole bottle of this step; GC detects, and reduces temperature to 100-110 ℃, after the raw material complete reaction; Suction filtration desalination under protection of nitrogen gas, filtrating joins in this four-hole bottle again;

(4) with 290-310 mass parts tetramethyl ethylene ketone solution be dissolved in 480-520 parts by volume mass concentrations be 97-99% 1, in the 2-ethylene dichloride, in 50-65min, be added drop-wise to then in the employed four-hole bottle of step (3); Stir, normal pressure is warming up to 80-90 ℃ of backflows and carries out transesterification reaction, and the n n dimetylaniline gas of generation absorbs with 18-22% hydrochloric acid; GC monitoring raw material reaction is complete; Suction filtration obtains product, reclaims toluene and 1, the 2-ethylene dichloride after the filtrating rectifying.