1. A preparation method for synthesizing isopropyl chloride by reacting isopropanol with phosgene is characterized by comprising the following specific steps:

s1: adding a proper amount of solid phosgene into a flask, adding a proper amount of dichloromethane into the flask, stirring and dissolving, and cooling the solution to-3 to-1 ℃;

s2: adding a proper amount of dimethylformamide into the cooled solution, keeping the temperature between 3 ℃ and-1 ℃, and continuously stirring for 20-30 min to obtain a phosgene solution;

s3: mixing a proper amount of isopropanol with dichloromethane, and stirring to obtain a mixed solution;

s4: adding phosgene solution into a reaction kettle, starting stirring, then arranging a dropping funnel above the reaction kettle, pouring the mixed solution obtained in the step S3 into the dropping funnel, opening a valve of the dropping funnel, controlling the liquid leakage speed, and adding the mixed solution into the reaction kettle under the condition of intense stirring for reaction;

s5: and after the reaction is finished, introducing nitrogen into the reaction kettle, driving phosgene and hydrogen chloride away, destroying phosgene, and sampling and analyzing to obtain a product.

2. The method for preparing isopropyl chloride by reacting isopropanol with phosgene as claimed in claim 1, wherein: in step S1, the weight ratio of the phosgene solid to the methylene chloride is 1: 3.

3. the method for preparing isopropyl chloride by reacting isopropanol with phosgene as claimed in claim 1, wherein: in the step S2, the adding amount of the dimethylformamide is 1-5% of the weight of the added solid phosgene.

4. The method for preparing isopropyl chloride by reacting isopropanol with phosgene as claimed in claim 1, wherein: in step S3, the weight ratio of isopropanol to dichloromethane is 1: 4, the weight of the isopropanol is 1/2 of the weight of the solid phosgene.

5. The method for preparing isopropyl chloride by reacting isopropanol with phosgene as claimed in claim 1, wherein: in step S4, the stirring speed is 800-1200 r/S.

6. The method for preparing isopropyl chloride by reacting isopropanol with phosgene as claimed in claim 1, wherein: in step S4, after phosgene solution is added into the reaction kettle, the temperature of the reaction kettle is adjusted to slowly rise to 30-35 ℃, then the mixed solution is dripped into the reaction kettle, and the reaction is carried out while the temperature is kept unchanged.

Background

Isopropyl chloride, also known as isopropanoyl carbonyl, is a colorless transparent liquid, generally exists in 1.0mol/L isopropyl chloride toluene solution, nD1.485, relative density 0.892, and has irritation. Isopropyl chloride is mainly used as an initiator during the polymerization of polyvinyl chloride resin, and also can be used as a pesticide intermediate, an ore flotation agent and the like; is also an intermediate of the fungicide diethofencarb; it can also be used as an initiator for radical polymerization, such as the initiation of vinyl chloride polymerization.

The traditional preparation method of isopropyl chloride comprises the steps of adding isopropanol into a phosgene introducing kettle, starting stirring, introducing phosgene through a phosgene flowmeter, wherein the phosgene has too high reaction activity, leakage and explosive accidents are easy to occur in the using, transporting and storing processes, and great harm is caused to people and the environment, so the danger coefficient of the mode is high; meanwhile, the reaction rate of the traditional synthesis process is low, and the preparation efficiency is influenced.

Disclosure of Invention

The invention aims to provide a preparation method for synthesizing isopropyl chloride by reacting isopropanol with phosgene, so as to solve the problems in the background technology.

In order to achieve the purpose, the invention provides the following technical scheme: a preparation method for synthesizing isopropyl chloride by reacting isopropanol with phosgene comprises the following specific steps:

s1: adding a proper amount of solid phosgene into a flask, adding a proper amount of dichloromethane into the flask, stirring and dissolving, and cooling the solution to-3 to-1 ℃;

s2: adding a proper amount of dimethylformamide into the cooled solution, keeping the temperature between 3 ℃ and-1 ℃, and continuously stirring for 20-30 min to obtain a phosgene solution;

s3: mixing a proper amount of isopropanol with dichloromethane, and stirring to obtain a mixed solution;

s4: adding phosgene solution into a reaction kettle, starting stirring, then arranging a dropping funnel above the reaction kettle, pouring the mixed solution obtained in the step S3 into the dropping funnel, opening a valve of the dropping funnel, controlling the liquid leakage speed, and adding the mixed solution into the reaction kettle under the condition of intense stirring for reaction;

s5: and after the reaction is finished, introducing nitrogen into the reaction kettle, driving phosgene and hydrogen chloride away, destroying phosgene, and sampling and analyzing to obtain a product.

Preferably, in step S1, the weight ratio of the solid phosgene to the dichloromethane is 1: 3.

preferably, in step S2, the amount of dimethylformamide added is 1 to 5% by weight of the added phosgene solid.

Preferably, in step S3, the weight ratio of isopropanol to dichloromethane is 1: 4, the weight of the isopropanol is 1/2 of the weight of the solid phosgene.

Preferably, in step S4, the rotation speed of stirring is 800 to 1200 r/S.

Preferably, in step S4, after the phosgene solution is added to the reaction kettle, the temperature of the reaction kettle is adjusted to be slowly raised to 30 to 35 ℃, the mixed solution is added dropwise, and then the reaction is carried out while maintaining the temperature.

Compared with the prior art, the invention has the beneficial effects that:

the method uses the solid phosgene as a reactant and dichloromethane as a solvent to dissolve the reactant, so that phosgene leakage is effectively avoided, and the safety is high; dimethyl formamide is used as an initiator and is mixed with dissolved solid phosgene, and the solid phosgene can be fully decomposed into phosgene under the low-temperature condition with the aid of the initiator, so that the reaction rate is greatly improved; the isopropanol and the dichloromethane are mixed and introduced into the dropping funnel, so that the reaction speed is convenient to control, the mixture is mixed with the phosgene solution under the condition of violent stirring, the reaction is sufficient and rapid, the operation is simple, the controllability is strong, and the synthesis efficiency is high.

Detailed Description

The invention provides a technical scheme that: a preparation method for synthesizing isopropyl chloride by reacting isopropanol with phosgene comprises the following specific steps:

s1: adding a proper amount of solid phosgene into a flask, adding a proper amount of dichloromethane into the flask, stirring and dissolving, and cooling the solution to-3 to-1 ℃;

s2: adding a proper amount of dimethylformamide into the cooled solution, keeping the temperature between 3 ℃ and-1 ℃, and continuously stirring for 20-30 min to obtain a phosgene solution;

s3: mixing a proper amount of isopropanol with dichloromethane, and stirring to obtain a mixed solution;

s4: adding phosgene solution into a reaction kettle, starting stirring, then arranging a dropping funnel above the reaction kettle, pouring the mixed solution obtained in the step S3 into the dropping funnel, opening a valve of the dropping funnel, controlling the liquid leakage speed, and adding the mixed solution into the reaction kettle under the condition of intense stirring for reaction;

s5: and after the reaction is finished, introducing nitrogen into the reaction kettle, driving phosgene and hydrogen chloride away, destroying phosgene, and sampling and analyzing to obtain a product.

Further, in step S1, the weight ratio of the phosgene solid to the methylene chloride is 1: 3.

further, in step S2, the amount of dimethylformamide added is 1 to 5% by weight of the added phosgene solid.

Further, in step S3, the weight ratio of isopropanol to dichloromethane is 1: 4, the weight of the isopropanol is 1/2 of the weight of the solid phosgene.

Further, in step S4, the rotation speed of stirring is 800-1200 r/S.

Further, in step S4, after the phosgene solution is added to the reaction kettle, the temperature of the reaction kettle is adjusted to slowly rise to 30-35 ℃, the mixed solution is dripped in, and then the reaction is carried out while maintaining the temperature.

The method uses the solid phosgene as a reactant and dichloromethane as a solvent to dissolve the reactant, so that phosgene leakage is effectively avoided, and the safety is high; dimethyl formamide is used as an initiator and is mixed with dissolved solid phosgene, and the solid phosgene can be fully decomposed into phosgene under the low-temperature condition with the aid of the initiator, so that the reaction rate is greatly improved; the isopropanol and the dichloromethane are mixed and introduced into the dropping funnel, so that the reaction speed is convenient to control, the mixture is mixed with the phosgene solution under the condition of violent stirring, the reaction is sufficient and rapid, the operation is simple, the controllability is strong, and the synthesis efficiency is high.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.