Clean process for preparing a chloroformyl-substituted benzene by oxidation of a tail gas hydrogen chloride from a chlorination reaction and a chloroacylation reaction and recycling of the resulting oxidation product chlorine gas into the chlorination reaction. The present invention provides a clean process for preparing a polymer-grade chloroformyl-substituted benzene.

Provided is a method of producing an acid halide solution that is useful in production of a polymerizable liquid-crystal compound. The method of producing an acid halide solution includes: a first step of reacting a specific dicarboxylic acid compound with a halogenating agent in a water-immiscible organic solvent in the presence of at least 1.1 equivalents and not more than 3.0 equivalents of an activator relative to the dicarboxylic acid compound to obtain a reaction liquid including a solution that contains an acid halide compound and an oily liquid that is immiscible with the solution containing the acid halide compound; and a second step of removing the oily liquid from the reaction liquid obtained in the first step to obtain a purified liquid containing the acid halide compound.

Provided is a method of producing an acid halide solution that is useful in production of a polymerizable liquid-crystal compound. The method of producing an acid halide solution includes: a first step of reacting a specific dicarboxylic acid compound with a halogenating agent in a water-immiscible organic solvent in the presence of at least 1.1 equivalents and not more than 3.0 equivalents of an activator relative to the dicarboxylic acid compound to obtain a reaction liquid including a solution that contains an acid halide compound and an oily liquid that is immiscible with the solution containing the acid halide compound; and a second step of removing the oily liquid from the reaction liquid obtained in the first step to obtain a purified liquid containing the acid halide compound.

The present disclosure provides a method of removing iodine (I.sub.2) and iodine-containing species from processes for producing trifluoroiodomethane (CF.sub.3I). The present disclosure further provides another method of removing iodine and iodine-containing species from trifluoroacetyl iodide (TFAI).

The present disclosure provides a method of removing iodine (I.sub.2) and iodine-containing species from processes for producing trifluoroiodomethane (CF.sub.3I). The present disclosure further provides another method of removing iodine and iodine-containing species from trifluoroacetyl iodide (TFAI).

The present disclosure provides a method of removing iodine (I.sub.2) and iodine-containing species from processes for producing trifluoroiodomethane (CF.sub.3I). The present disclosure further provides another method of removing iodine and iodine-containing species from trifluoroacetyl iodide (TFAI).

The present disclosure generally relates to processes for converting acrylate esters or a derivative thereof to difluoropropionic acid or a derivative thereof. This process is generally performed using fluorine gas in a hydrofluorocarbon solvent. In particular, a continuous process for fluorinating a double bond is disclosed, the process comprising forming a reaction stream comprising a compound of formula 1 or formula 5 dissolved in a hydrofluorocarbon or fluorocarbon solvent, ##STR00001##
wherein R.sub.1 is hydroxy, alkoxy, chloro, or OC(O)CH?CH.sub.2; the reaction stream flowing through a continuous fluorination reactor at a flow rate of from about 0.2 mL/minute to about 2 mL/minute and fluorine gas flows through the continuous fluorination reactor at a gas flow rate of from about 0.2 mmol/minute to about 2 mmol/minute; whereby reaction of the compound of formula 1 or formula 5 with the fluorine gas forms a compound of formula 2 or formula 6 ##STR00002##
wherein R.sub.2 is hydroxy, alkoxy, chloro, or OC(O)CHFCH.sub.2F.

The present disclosure generally relates to processes for converting acrylate esters or a derivative thereof to difluoropropionic acid or a derivative thereof. This process is generally performed using fluorine gas in a hydrofluorocarbon solvent. In particular, a continuous process for fluorinating a double bond is disclosed, the process comprising forming a reaction stream comprising a compound of formula 1 or formula 5 dissolved in a hydrofluorocarbon or fluorocarbon solvent, ##STR00001##
wherein R.sub.1 is hydroxy, alkoxy, chloro, or OC(O)CH?CH.sub.2; the reaction stream flowing through a continuous fluorination reactor at a flow rate of from about 0.2 mL/minute to about 2 mL/minute and fluorine gas flows through the continuous fluorination reactor at a gas flow rate of from about 0.2 mmol/minute to about 2 mmol/minute; whereby reaction of the compound of formula 1 or formula 5 with the fluorine gas forms a compound of formula 2 or formula 6 ##STR00002##
wherein R.sub.2 is hydroxy, alkoxy, chloro, or OC(O)CHFCH.sub.2F.

Impurities such as sulfur dioxide (SO.sub.2) are removed from trifluoroacetyl chloride (TFAC) through distillation, adsorption, or a combination thereof, and/or including the formation of an azeotrope or azeotrope-like composition including effective amounts of sulfur dioxide (SO.sub.2) and trifluoroacetyl chloride (TFAC). The trifluoroacetyl chloride (TFAC) thus purified may then be used in the manufacture of trifluoroiodomethane (CF.sub.3I). Also disclosed are azeotropes and azeotrope like compositions of sulfur dioxide (SO.sub.2) and trifluoroacetyl chloride (TFAC).

Impurities such as sulfur dioxide (SO.sub.2) are removed from trifluoroacetyl chloride (TFAC) through distillation, adsorption, or a combination thereof, and/or including the formation of an azeotrope or azeotrope-like composition including effective amounts of sulfur dioxide (SO.sub.2) and trifluoroacetyl chloride (TFAC). The trifluoroacetyl chloride (TFAC) thus purified may then be used in the manufacture of trifluoroiodomethane (CF.sub.3I). Also disclosed are azeotropes and azeotrope like compositions of sulfur dioxide (SO.sub.2) and trifluoroacetyl chloride (TFAC).