CN102617274B - Method for preparing 2-chlorine-3,3,3-trifluoropropene - Google Patents

Abstract

The invention discloses a method for preparing 2-chlorine-3,3,3-trifluoropropene. The method includes the two steps: (a) performing nucleophilic substitution reaction of 1,1,2,3-trifluoropropene and fluorinated reagents to obtain 1,1,2-trichlorine-3-fluoropropene; and (b) performing gas phase fluorination reaction of the 1,1,2-trichlorine-3-fluoropropene and hydrogen fluoride to obtain the 2-chlorine-3,3,3-trifluoropropene. The method for preparing the 2-chlorine-3,3,3-trifluoropropene has the advantages of moderate reaction conditions and high conversion rate and selectivity, and is mainly used for preparing the 2-chlorine-3,3,3-trifluoropropene.

Description

A kind of preparation method of 2-chloro-3,3,3 ,-trifluoropropene

Technical field

The present invention relates to a kind of preparation method of 2-chloro-3,3,3 ,-trifluoropropene, relating in particular to 1,1,2,3-tetrachloro propylene is the preparation method of raw material through nucleophilic substitution, the synthetic 2-chloro-3,3,3 ,-trifluoropropene of gas phase fluorination two steps.

Background technology

2-chloro-3,3,3 ,-trifluoropropene (HCFC-1233xf) is the raw material of synthetic 2,3,3,3-tetrafluoeopropene (HFO-1234yf).HFO-1234yf, the latent value of its ozone depletion is zero, the latent value of Greenhouse effect is 4, has good environmental performance.Be considered to the ideal substitute of HFC-134a.

Chinese patent CN101874009A discloses the method for HCFC-1233xf of preparation a kind of, the method is with 1,1,2,3-tetrachloro propylene is raw material, gas phase fluorination synthesizes HCFC-1233xf, for fear of 1,1,2, when 3-tetrachloro propylene high-temperature, easily generate polymkeric substance or de-HCl and generate alkynes, the method is 1,1, and 2, in 3-tetrachloro propylene, add a small amount of Resorcinol, quadrol, Diisopropylamine etc. and improve 1 as stablizer, the stability of 1,2,3-tetrachloro propylene, and the method temperature of reaction is higher, it is 200 DEG C～330 DEG C.

Summary of the invention

Technical problem to be solved of the present invention is to overcome the deficiency existing in background technology, provides one to avoid the preparation method of the 2-chloro-3,3,3 ,-trifluoropropene of 1,1,2,3-tetrachloro propylene autohemagglutination or de-HCl.

In order to realize object of the present invention, the present invention is with 1,1,2,3-tetrachloro propylene for raw material, and through the preparation method of nucleophilic substitution, the synthetic 2-chloro-3,3,3 ,-trifluoropropene of gas phase fluorination two steps, reaction process is as follows:

The preparation method who the invention provides a kind of 2-chloro-3,3,3 ,-trifluoropropene, comprises the following steps:

(a) 1,1,2,3-tetrachloro propylene and fluorination reagent generation nucleophilic substitution reaction obtain the chloro-3-fluorine of 1,1,2-tri-propylene;

(b) under catalyzer exists, 1,1,2-tri-chloro-3-fluorine propylene and hydrogen fluoride generation gas phase fluorination obtain 2-chloro-3,3,3 ,-trifluoropropene.

Fluorination reagent described in step of the present invention (a) is alkaline metal fluoride cpd, basic metal is fluoridized hydrogen salt, tertiary amine hydrofluoride, fluoridize quaternary amine or fluoridize quaternary amine hydrofluoride, wherein alkaline metal fluoride cpd is Sodium Fluoride, Potassium monofluoride or cesium fluoride, it is sodium bifluoride that basic metal is fluoridized hydrogen salt, potassium hydrogen fluoride, hydrogen fluoride caesium or bifluoride hydrogen potassium, the general formula of tertiary amine hydrogen fluoride salts is: tertiary amine nHF, 0 < n≤3.0 in formula, tertiary amine is triethylamine, Tri-n-Propylamine, diisopropylethylamine, tri-n-amyl amine, tri-n-butylamine, pyridine or 2-picoline, fluoridizing quaternary amine is tetrabutyl ammonium fluoride, Methanaminium, N,N,N-trimethyl-, fluoride, tetrapropyl Neutral ammonium fluoride, ethyl-trimethyl Neutral ammonium fluoride or benzyl tributyl Neutral ammonium fluoride, quaternary amine hydrofluoride is tetrapropyl Neutral ammonium fluoride two hydrofluorides, tetrabutyl ammonium fluoride two hydrofluorides, but be not limited to above lifted compound.

In step (a), the mol ratio of fluorination reagent and 1,1,2,3-tetrachloro propylene is 1: 1～10: 1, and the reaction times is 0.5h～10h, and temperature of reaction is 20 DEG C～130 DEG C.Preferred reaction conditions: the mol ratio of fluorination reagent and 1,1,2,3-tetrachloro propylene is 1.5: 1～5: 1, and the reaction times is 1h～5h, and temperature of reaction is 50～120 DEG C.

Step in the present invention (b) is under catalysts for gas phase fluorination exists, gas phase fluorination does not limit catalysts for gas phase fluorination, any known catalysts for gas phase fluorination is all applicable to the present invention, for example: chromic oxide, chromium fluoride, the chromic oxide of fluoridizing, aluminum fluoride, the aluminum oxide of fluoridizing, be carried on the chromic oxide on gac, aluminum fluoride, magnesium fluoride, chromic oxide and the activated carbon supported SbCl that contains various metals (as Zn, Co, Ni, Ge, In etc.) ₅or TiCl ₄deng, the chromium oxide catalyst of preferred fluorinated.

In step (b), the mol ratio of hydrogen fluoride and the chloro-3-fluorine of 1,1,2-tri-propylene is 5: 1～20: 1, and be 2～10 seconds duration of contact, and temperature of reaction is 180～220 DEG C.Preferred reaction conditions is: the mol ratio of hydrogen fluoride and the chloro-3-fluorine of 1,1,2-tri-propylene is 10: 1～15: 1,3～6 seconds duration of contact, 195～210 DEG C of temperature of reaction.

In step (b), gas phase fluorination pressure is little on the impact of reaction, is all very suitable under the condition of normal atmosphere and pressurization.In step (b), not crucial for the type of reactor of fluoridation, can use tubular reactor, fluidized-bed reactor etc.In addition, adiabatic reactor or isothermal reactor also can be used to the present invention.

Preferred version of the present invention comprises the following steps:

(a) 1,1,2,3-tetrachloro propylene reacts and obtains the chloro-3-fluorine of 1,1,2-tri-propylene with triethylamine two hydrofluorides, and temperature of reaction is 110 DEG C, and the reaction times is 2h, and the mol ratio of fluorination reagent and 1,1,2,3-tetrachloro propylene is 3: 1;

(b) 1,1,2-tri-chloro-3-fluorine propylene and hydrogen fluoride generation gas phase fluorination obtain 2-chloro-3,3,3 ,-trifluoropropene, and the mol ratio of hydrogen fluoride and the chloro-3-fluorine of 1,1,2-tri-propylene is 15: 1,5 seconds duration of contact, 200 DEG C of temperature of reaction.

Compared with prior art, the present invention is first by 1,1,2,3-tetrachloro propylene is converted into metastable intermediate 1,1, the chloro-3-fluorine of 2-tri-propylene, and then carry out gas phase fluorination synthetic intermediate 1,1, the chloro-3-fluorine of 2-tri-propylene, thus effectively avoid 1,1,2,3-tetrachloro propylene autohemagglutination or de-HCl, without adding Resorcinol, quadrol or Diisopropylamine stablizer, and the reaction conditions of every step reaction is comparatively gentle, and transformation efficiency and selectivity are higher; And method in documents is by the raw material 1,1,2 in the first step reaction, in 3-tetrachloro propylene, needs to add a small amount of Resorcinol, quadrol, Diisopropylamine etc. and improve 1,1,2 as stablizer, the stability of 3-tetrachloro propylene.

Embodiment

Followingly the present invention is described in further detail to explanation in conjunction with the embodiments, but does not limit the scope of the invention.

Embodiment 1

1,1,2,3-tetrachloro propylene and fluorination reagent generation nucleophilic substitution reaction obtain the chloro-3-fluorine of 1,1,2-tri-propylene, and fluorination reagent is Potassium monofluoride.

In the dry there-necked flask of the 50mL that magnetic agitation, thermometer, condensing works are housed, add successively 1,1,2,3-tetrachloro propylene (5.0g, 0.028mol), glycol ether 30mL, under constantly stirring, be heated to 120 DEG C, under constantly stirring, add Potassium monofluoride (4.87g, 0.084mol), Potassium monofluoride and 1 again, 1, the mol ratio of 2,3-tetrachloro propylene is 3, is to react 2h at 120 DEG C in temperature.Reaction product adopts gas chromatographic analysis, and result shows that 1,1,2,3-tetrachloro propylene conversion is that the chloro-3-fluorine of 98%, 1,1,2-tri-Propylene Selectivity is 90%.

Embodiment 2～6

The operating process of embodiment 2～6 is similar to embodiment 1, and difference is used fluorination reagent difference, and reaction result is as shown in table 1.

Table 1

Embodiment	Fluorination reagent	Transformation efficiency (%)	Selectivity (%)
				2	Sodium Fluoride	54	85
3	Cesium fluoride	99	92
				4	Potassium hydrogen fluoride	85	95
5	Bifluoride hydrogen potassium	45	98
				6	Hydrogen fluoride caesium	90	94

Embodiment 7

1,1,2,3-tetrachloro propylene and fluorination reagent generation nucleophilic substitution reaction obtain the chloro-3-fluorine of 1,1,2-tri-propylene, and fluorination reagent is triethylamine two hydrofluorides.

In the dry there-necked flask of the 50mL that magnetic agitation, thermometer, condensing works are housed, add nucleophilic fluorination agent triethylamine two hydrofluoride (NEt ₃2HF) (10.8g, 0.084mol), adds 1,1,2,3-tetrachloro propylene (5.0g, 0.028mol) subsequently, and the mol ratio of triethylamine two hydrofluorides and 1,1,2,3-tetrachloro propylene is 3, is to react 2h at 110 DEG C in temperature of reaction.Reaction product adopts gas chromatographic analysis, and result shows that the transformation efficiency of 1,1,2,3-tetrachloro propylene is that the selectivity of the chloro-3-fluorine of 90%, 1,1,2-tri-propylene is 95%.

Embodiment 8～15

The operating process of embodiment 8～15 is similar to embodiment 7, and difference is mol ratio, temperature of reaction and the reaction times that changes triethylamine two hydrofluorides and 1,1,2,3-tetrachloro propylene, and reaction result is as shown in table 2.

Embodiment 16～22

The operating process of embodiment 16～22 is similar to embodiment 7, and difference is used fluorination reagent difference, and reaction result is as shown in table 3.

Table 2

Table 3

Embodiment	Nucleophilic fluorination reagent	Transformation efficiency (%)	Selectivity (%)
				16	Tri-n-Propylamine two hydrofluorides	85	97
17	Diisopropylethylamine two hydrofluorides	80	98
				18	Tri-n-butylamine two hydrofluorides	95	96
19	Tri-n-amyl amine two hydrofluorides	80	96
				20	Pyridine one hydrofluoride	78	95
21	Pyrazine one hydrofluoride	85	94
				22	2-picoline one hydrofluoride	78	92

Embodiment 23

1,1,2,3-tetrachloro propylene and fluorination reagent generation nucleophilic substitution reaction obtain the chloro-3-fluorine of 1,1,2-tri-propylene, and fluorination reagent is tetrabutyl ammonium fluoride.

In the dry there-necked flask of the 50mL that magnetic agitation, thermometer, condensing works are housed, add nucleophilic fluorination agent tetrabutyl ammonium fluoride ((C ₄h ₉) ₄nF3H ₂o) (21.9g, 0.084mol), water (4.5g, 0.252mol) adds 1,1 subsequently, 2,3-tetrachloro propylene (5.0g, 0.028mol), fluorination reagent and 1, the mol ratio of 1,2,3-tetrachloro propylene is 3, is to react 2h at 100 DEG C in temperature of reaction.Reaction product adopts gas chromatographic analysis, and result shows that the transformation efficiency of 1,1,2,3-tetrachloro propylene is that the selectivity of the chloro-3-fluorine of 98%, 1,1,2-tri-propylene is 94%.

Embodiment 24～29

The operating process of embodiment 24～29 is similar to embodiment 23, and difference is used fluorination reagent difference, and reaction result is as shown in table 4.

Table 4

Embodiment	Fluorination reagent	Transformation efficiency (%)	Selectivity (%)
				24	Methanaminium, N,N,N-trimethyl-, fluoride	90	92
25	Tetrapropyl Neutral ammonium fluoride	94	93
				26	Ethyl-trimethyl Neutral ammonium fluoride	85	90
27	Benzyl tributyl Neutral ammonium fluoride	94	92
				28	Tetrabutyl ammonium fluoride two hydrofluorides	80	95
29	Tetrapropyl Neutral ammonium fluoride two hydrofluorides	75	95

Embodiment 30

Be raw material preparing 2-chloro-3,3,3-trifluoropropene by gas-phase fluorination with the chloro-3-fluorine of 1,1,2-tri-propylene.

In the nickel pipe fixed-bed tube reactor that is 38mm at internal diameter, pack 60ml chromium sesquioxide fluorination catalyst into, pass into HF and the chloro-3-fluorine of 1,1,2-tri-propylene reacts, reaction conditions is: HF and 1, the mol ratio of the chloro-3-fluorine of 1,2-tri-propylene is 15,200 DEG C of temperature of reaction, duration of contact 5s, synthesis under normal pressure, after reaction 20h, reaction product is removed after HCl and HF through washing, alkali cleaning, with gas chromatographic analysis 1, the transformation efficiency of the chloro-3-fluorine of 1,2-tri-propylene is 100%, 2-chloro-3, the selectivity of 3,3-trifluoro propene is 95%.

Embodiment 31～36

Embodiment 31～36 is similar to the operation of embodiment 30, and difference is reaction conditions difference, and reaction result is as shown in table 5.

Table 5

The above, be only part embodiment of the present invention, not the present invention done to any pro forma restriction, any simple amendment that every foundation technical spirit of the present invention is done above-described embodiment, equivalent variations and modification, all belong within the scope of technical solution of the present invention.

Claims (4)

1. a preparation method for 2-chloro-3,3,3 ,-trifluoropropene, comprises the following steps:

(a) 1,1,2,3-tetrachloro propylene and fluorination reagent generation nucleophilic substitution reaction obtain 1, the chloro-3-fluorine of 1,2-tri-propylene, wherein said fluorination reagent is that alkaline metal fluoride cpd, basic metal are fluoridized hydrogen salt, tertiary amine hydrofluoride, fluoridize quaternary amine or fluoridized quaternary amine hydrofluoride;

(b) under catalyzer exists, 1,1,2-tri-chloro-3-fluorine propylene and hydrogen fluoride generation gas phase fluorination obtain 2-chloro-3,3,3 ,-trifluoropropene.

2. the preparation method of 2-chloro-3,3,3 ,-trifluoropropene according to claim 1 and 2, it is characterized in that fluorination reagent and 1,1 in step (a), 2, the mol ratio of 3-tetrachloro propylene is 1: 1～10: 1, and the reaction times is 0.5h～10h, and temperature of reaction is 20 DEG C～130 DEG C.

3. the preparation method of 2-chloro-3,3,3 ,-trifluoropropene according to claim 1, the mol ratio that it is characterized in that the middle hydrogen fluoride of step (b) and the chloro-3-fluorine of 1,1,2-tri-propylene is 5: 1～20: 1, be 2 seconds～10 seconds duration of contact, and temperature of reaction is 180 DEG C～220 DEG C.

4. the preparation method of 2-chloro-3,3,3 ,-trifluoropropene according to claim 1, comprises the following steps:

(a) 1,1,2,3-tetrachloro propylene reacts and obtains the chloro-3-fluorine of 1,1,2-tri-propylene with triethylamine two hydrofluorides, and temperature of reaction is 110 DEG C, and the reaction times is 2h, and the mol ratio of fluorination reagent and 1,1,2,3-tetrachloro propylene is 3: 1;

(b) 1,1,2-tri-chloro-3-fluorine propylene and hydrogen fluoride generation gas phase fluorination obtain 2-chloro-3,3,3 ,-trifluoropropene, and the mol ratio of hydrogen fluoride and the chloro-3-fluorine of 1,1,2-tri-propylene is 15: 1,5 seconds duration of contact, 200 DEG C of temperature of reaction.