CN1046125C - Preparation method of dicyclopentadienyl titanium dichloride - Google Patents

Abstract

The invention discloses a preparation method of dicyclopentadienyl titanium dichloride (namely dicyclopentadienyl titanium dichloride), which uses dicyclopentadiene as a raw material and toluene, xylene or ethylbenzene as a solvent, wherein the adding amount of the dicyclopentadienyl titanium dichloride is 100-1000 ml/100 g TiCl₄. The invention solves the problems of low yield, long purification time, environmental pollution and the like, has the advantages of less side reaction, high yield, low production cost, short purification time, less environmental pollution and the like, and is widely suitable for the fields of chemical industry, medicine and the like.

Description

The preparation method of dicyclic pentylene titanium dichloride

The present invention relates to a kind of dicyclic pentylene titanium dichloride and (be commonly called as cyclopentadienyl titanium dichloride, molecular formula: (C ₅H ₅) ₂TiCl ₂) the preparation method.

In the prior art, external " Organometallic Sytheses ", VOl.1, P75, AcademicPress (1965) have reported a kind of synthetic and method of purification.This method be at first dicyclopentadiene at N ₂Protection Pintsch process down is the cyclosiloxane monomer pentadiene, the cyclopentadiene of distillation preparation just is added drop-wise in the there-necked flask of tetrahydrofuran (THF) (perhaps glycol dimethyl ether) solvent that sodium sand is housed, at N ₂Under the atmosphere sodium sand is fully reacted completely, prepare the cyclopentadienyl sodium tetrahydrofuran (THF) of (being called for short luxuriant sodium) (perhaps ethylene glycol monomethyl ether) solution thus, then, be added drop-wise in the flask that dry benzene and titanium tetrachloride are housed and react, the reaction product filtration under diminished pressure, filter cake is utilized apparatus,Soxhlet's, with trichloromethane is that solvent extracts repeatedly, separates out red crystallization after the extraction liquid cooling, filters and also uses the alkane washing precipitation, air drying gets product, and yield is greater than 50%.For purifying, available trichloromethane recrystallization, 289～291 ℃ of the molten points of product use benzene as solvent when this method is synthetic, and yield is on the low side, and benzene is very harmful to human body.Purification is to use trichloromethane as solvent, and apparatus,Soxhlet's is extracting repeatedly, and a collection of production life cycle of purifying is very long, and trichloromethane is volatile, and loss amount is big, and it is higher to make it cost, and has caused the serious environmental pollution.

Domestic, chemical reagent, 1983,5 (6), 363～379 have reported a kind of synthetic and method of purification, and this method is cracked into the cyclosiloxane monomer pentadiene to dicyclopentadiene and prepares the tetrahydrofuran solution of cyclopentadienyl sodium thus and aforementioned external report the same, and different is at N ₂Protection the tetrahydrofuran solution that cyclopentadienyl is received, is added drop-wise to and reacts in the flask that tetrahydrofuran (THF) and titanium tetrachloride are housed down, and reaction product is carried out filtration under diminished pressure, gets filter cake.Be solvent with the filter cake trichloromethane then,, extracting solution at room temperature placed a few hours after-filtration, get red cyclopentadienyl titanium dichloride crystal with apparatus,Soxhlet's extracting repeatedly.Be to improve purity, available chloroform or be that solvent carries out extraction second time with toluene, yield can reach 60%.In this synthetic method, cancelled benzene, all adopted tetrahydrofuran (THF), reduced the pollution of benzene, helped protecting environment environment as solvent as solvent, but because of tetrahydrofuran (THF) as this synthetic solvent, need use LiALH earlier ₄Handle, to remove wherein superoxide and moisture, step is more in distillation (collecting 65～66 ℃ of cuts) then.Tetrahydrofuran (THF) is more expensive and the volatilization loss amount is big, has caused synthetic cost higher.Method of purification is the same with external method of purification, utilizes apparatus,Soxhlet's, uses trichloromethane as extraction agent, trichloromethane is volatile, loss amount is big, the cost for purification height, environmental pollution is serious, this method preparation and the product of purifying, detect with abroad the infrared standard spectrogram of Pfaltz Bauer company is consistent through infrared spectrometer, fusing point is 289 ℃, ultimate analysis: C content 47.81%, H content 4.12%, Ti content 19.20%, Cl content 28.45%.

The objective of the invention is to overcome the defective that prior art exists, use new solvent and extraction agent, to improve product yield, reduce cost, shorten the purification time, improve plant capacity, to avoid environmental pollution, the purity of product is reached more than 99% (weight).

In order to achieve the above object; the present invention has adopted following technical scheme: earlier with dicyclopentadiene cracking system cyclopentadiene; in tetrahydrofuran solution, produce cyclopentadienyl sodium then with the sodium sand reaction; the gained mixed solution is handled by the following method: (1) uses toluene; one of dimethylbenzene or ethylbenzene or its mixture as solvent; by 100 100～1000 milliliters of solvents of gram titanium tetrachlorides; solvent and titanium tetrachloride are placed reactor; in nitrogen protection; under stirring and the cooling conditions; slowly add the cyclopentadienyl sodium solution by metering; reacted under the room temperature 1～3 hour; reclaim solvent; adopt low-temperature reduced-pressure to steam to doing to the greatest extent; (2) use N then; dinethylformamide; N; a kind of or its mixed solution of N-N,N-DIMETHYLACETAMIDE is made extraction agent; use 100～300 milliliters of extraction agents by 10 gram dicyclic pentylene titanium dichlorides; extraction agent is added in the reactor; stir, dicyclic pentylene titanium dichloride is fully dissolved, filtration under diminished pressure; again filtrate heating and underpressure distillation are done to most; cooling with alkane or aromatic hydrocarbons washing, is filtered; the trichloromethane crystallization gets red dicyclic pentylene titanium dichloride.

In aforesaid operating process, must add solvent and extraction agent by described measures range, promptly its add-on is not too high or too low.The amount of solvent is very little the time, and its side reaction is many, and heat effect is big, and temperature of reaction is wayward; Solvent adds when too much, and its side reaction also can increase, and the yield of dicyclic pentylene titanium dichloride product is reduced.When the consumption of extraction agent is crossed when low, incomplete to the dissolving of product, yield is reduced; There is no need to use too much extraction agent, consumption too much not only can cause unnecessary waste, also can make the aftertreatment quantitative change big, has increased the load of aftertreatment.

The present invention's technical scheme preferably can be: in preparation dicyclic pentylene titanium dichloride process, the adding mode of cyclopentadienyl sodium solution is slowly to drip, because the thermal discharge of reaction is big, adopt the slow dropping can controls reaction speed, avoid the temperature rise of reaction system too high, adopt slow dropping mode, be aided with water quench (the available where necessary refrigerated water of bigger device) simultaneously, temperature that can the stopping reaction system, and at room temperature reacted 1～3 hour, reach good technical effect.

The present invention's technical scheme preferably also can be: extraction agent gradation used in the purification process adds, generally can divide 2～3 addings as one sees fit, because the dicyclic pentylene titanium dichloride in the extraction agent gradation dissolution reactor of same amount is than once dissolving is more complete, better effects if is beneficial to the yield that improves product.

Compared with prior art, the present invention has following tangible advantage:

1, yield height: replace benzene with toluene, dimethylbenzene or ethylbenzene as solvent when synthetic, than replacing benzene with tetrahydrofuran (THF), energy is controls reaction speed effectively, reduce side reaction, improve the yield of cyclopentadienyl titanium dichloride, its yield is up to more than 70%, and the employing prior art, the yield of cyclopentadienyl titanium dichloride only reaches 50%～60%;

2, cost is low: the toluene boiling point is high 30～40 ℃ than benzene and tetrahydrofuran (THF), and when distillation was reclaimed, loss amount was little, is convenient to recycle, and has reduced synthetic cost, and its cost only is about half of prior art;

3, the purification time is short: use N during purification, dinethylformamide or N, the N-N,N-DIMETHYLACETAMIDE is as extraction agent, because of they are big to the solubleness of cyclopentadienyl titanium dichloride more than trichloromethane to the solubleness of cyclopentadienyl titanium dichloride, and selectivity will be got well, and therefore, does not need to extract repeatedly with apparatus,Soxhlet's, shorten the purification time, reduced purification step.The purification time of product of the present invention is generally in 5 hours, and required purification time of existing technology is all more than 12 hours;

4, environmental pollution is few: N, and dinethylformamide and N,N-dimethylacetamide moderate boiling point, volatilization, loss amount is little, and when having reduced cost for purification, environmental pollution also significantly reduces.

Below the present invention is described in further detail by specific embodiment.

Embodiment 1

100～180ml tetrahydrofuran (THF) and 5.8 gram sodium sands are housed in a 500ml four-hole boiling flask, this four-hole boiling flask is installed in the thermostatic water-circulator bath device, fill with cold water, load onto logical N ₂Device, agitator, reflux condensing tube, dropping funnel.At N ₂Protection is stirred down, slowly splashes into the 20～30ml cyclopentadiene and the 20～40ml tetrahydrofuran (THF) mixed solution that are newly distilled by Pintsch process; after dripping off, reacted 2～3 hours down, obtain cyclopentadienyl sodium (being commonly called as luxuriant sodium) solution thus at 30～40 ℃; this solution is red; then, under nitrogen protection, in the 1000ml reaction flask; add 25～250ml dry toluene and 25 gram titanium tetrachlorides; the cyclopentadienyl sodium solution for preparing is slowly splashed in this reaction flask, and the cold water cooling is stirred.Add in stirring at room reaction 1～3 hour.Reclaim solvent, adopt low-temperature reduced-pressure to steam to doing to the greatest extent.With 250～750ml N, dinethylformamide joins in the container at twice, fully dissolves contained cyclopentadienyl titanium dichloride, and filtration under diminished pressure is collected filtrate.Utilize the thermostatic water-circulator bath device, heating is under the decompression (condition of high vacuum degree), decompression steams N, dinethylformamide, cooling adds 50～100ml cyclohexane cleaning product, pour B then into, filtration under diminished pressure is used the trichloromethane crystallization then, and vacuum-drying gets product cyclopentadienyl titanium dichloride 22.04 grams, yield is 70.20%, and infrared spectrometer detects its infrared spectrogram and abroad Pfaltz﹠Bauer company infrared spectra standard spectrogram is consistent.DT-30 type differential thermal analyzer carries out differential thermal analysis, absorption peak occurs at 289.5 ℃, and this absorbs honeybee is (C ₅H ₅) ₂TiCl ₂Due to the fusion strong endothermic, so fusing point is 289.5 ℃, liquid chromatogram measuring purity is 99.43%, and ultimate analysis C is 47.83%, H is 4.09%, and Ti is 19.21%, Cl be 28.42% and theoretical value C be 48.28%, H is 4.05%, and Ti is 19.24%, and Cl is 28.28% approaching.The purification time of this example is 4.8 hours.

Embodiment 2

With dimethylbenzene (contain the neighbour,, contraposition) make solvent, make extraction agent with N,N-dimethylacetamide, its add-on, working method, operational condition be all with example 1, dicyclic pentylene titanium dichloride product 22.11 grams, yield is 70.42%.By aforementioned analysis determining method, its result: 290.3 ℃ of fusing points, purity 99.47%, ultimate analysis C is 48.02%, and H is 4.07%, and Ti is 19.22%, and Cl is 28.39%.

Embodiment 3

Make solvent with ethylbenzene, use N, dinethylformamide and N,N-dimethylacetamide mixture are made extraction agent, and its add-on, working method and operational condition get dicyclic pentylene titanium dichloride product 22.01 grams all with example 1, and yield is 70.10%.By the analysis determining method of example 1, its result: fusing point is 289.9 ℃, and purity is 99.37%.Ultimate analysis C is 48.19%, and H is 4.04%, and Ti is 19.18%, and Cl is 28.30%.

Embodiment 4

Make solvent with toluene and ethyl benzene mixtures, use N, dinethylformamide is made extraction agent, and its add-on, working method and operational condition get dicyclic pentylene titanium dichloride product 22.17 grams all with example 1, and yield is 70.61%.By the analysis determining method of example 1, its result: 290.1 ℃ of fusing points, purity 99.26%.Ultimate analysis C is 48.13%, and H is 4.06%, and Ti is 19.20%, and Cl is 28.22%.

Embodiment 5 (Comparative Examples)

The preparation of the preparation of cyclopentadienyl titanium dichloride and embodiment 1 is all consistent on raw material input amount and synthetic method.But when purifying, without N, dinethylformamide or N, the N-N,N-DIMETHYLACETAMIDE is divided into four parts to the solid of the solution decompression evaporate to dryness gained in the reactor, each portion that moves into, put into apparatus,Soxhlet's, extract repeatedly with the 500ml trichloromethane, united extraction liquid concentrates extracting solution, separate out red crystals, filter and with alkane wash crystallization thing, vacuum, dry must product, yield is greater than 70%.It is extraction agent extracting repeatedly with the trichloromethane that this embodiment utilizes apparatus,Soxhlet's, and the purification spended time was than long 8 hours of embodiment 1 spended time.Infrared spectrogram and Pfaltz﹠amp; Bauer company standard spectrogram unanimity.DT-30 type differential thermal analyzer test fusing point is 290 ℃, and liquid chromatography test content is 99.15%, and ultimate analysis C is 48.11%, and H is 4.07%, and Ti is 19.21%, and Cl is 28.35%.

Claims (3)

1, a kind of preparation method of dicyclic pentylene titanium dichloride, earlier with dicyclopentadiene cracking system cyclopentadiene, in tetrahydrofuran solution, produce cyclopentadienyl sodium then with the sodium sand reaction, mixed solution in solvent with titanium tetrachloride reaction, through purify dicyclic pentylene titanium dichloride, the invention is characterized in:

(1) with one of toluene, dimethylbenzene or ethylbenzene or its mixture as solvent; by 100 100～1000 milliliters of solvents of gram titanium tetrachlorides; solvent and titanium tetrachloride are placed reactor; under nitrogen protection, stirring and cooling conditions; slowly add the cyclopentadienyl sodium solution by metering, reacted under the room temperature 1～3 hour, reclaim solvent; adopt low-temperature reduced-pressure to steam to doing to the greatest extent, then

(2) use N, a kind of or its mixed solution of dinethylformamide, N,N-dimethylacetamide is made extraction agent, use 100～300 milliliters of extraction agents by 10 gram dicyclic pentylene titanium dichlorides, extraction agent is added in the reactor, stir, dicyclic pentylene titanium dichloride is fully dissolved, filtration under diminished pressure is done cooling with filtrate heating and underpressure distillation again to most, with alkane or aromatic hydrocarbons washing, filter, use the trichloromethane crystallization, get red dicyclic pentylene titanium dichloride.

2, preparation method according to claim 1 is characterized in that preparing in the dicyclic pentylene titanium dichloride process, and the adding mode of cyclopentadienyl sodium solution is slowly to drip.

3, preparation method according to claim 1 and 2 is characterized in that the used extraction agent gradation of purification process adds.