A naphthalenedicarboxylic acid dichloride production method includes causing a reaction between naphthalenedicarboxylic acid and a chlorinating agent at a reaction temperature of 20 C. or higher and 75 C. or lower in presence of a solvent including tetrahydrofuran. The causing a reaction in the naphthalenedicarboxylic acid dichloride production method is preferably performed in presence of N,N-disubstituted formamide.

A naphthalenedicarboxylic acid dichloride production method includes causing a reaction between naphthalenedicarboxylic acid and a chlorinating agent at a reaction temperature of 20 C. or higher and 75 C. or lower in presence of a solvent including tetrahydrofuran. The causing a reaction in the naphthalenedicarboxylic acid dichloride production method is preferably performed in presence of N,N-disubstituted formamide.

A naphthalenedicarboxylic acid dichloride production method includes causing a reaction between naphthalenedicarboxylic acid and a chlorinating agent at a reaction temperature of 20 C. or higher and 75 C. or lower in presence of a solvent including tetrahydrofuran. The causing a reaction in the naphthalenedicarboxylic acid dichloride production method is preferably performed in presence of N,N-disubstituted formamide.

The disclosure provides a method for synthesizing paraphthaloyl chloride through terephthalic acid chlorination in a reaction mode of a microchannel continuous flow. Compared with an existing technology, this method has characteristics of accurate control of reaction conditions, high phosgene/triphosgene utilization ratio, low catalyst dosage, high TPA conversion ratio within few tens of seconds of reaction time, high TPC yield and the like.

The disclosure provides a method for synthesizing paraphthaloyl chloride through terephthalic acid chlorination in a reaction mode of a microchannel continuous flow. Compared with an existing technology, this method has characteristics of accurate control of reaction conditions, high phosgene/triphosgene utilization ratio, low catalyst dosage, high TPA conversion ratio within few tens of seconds of reaction time, high TPC yield and the like.

The disclosure provides a method for synthesizing paraphthaloyl chloride through terephthalic acid chlorination in a reaction mode of a microchannel continuous flow. Compared with an existing technology, this method has characteristics of accurate control of reaction conditions, high phosgene/triphosgene utilization ratio, low catalyst dosage, high TPA conversion ratio within few tens of seconds of reaction time, high TPC yield and the like.

Provided is a method for industrially advantageously producing a fluorinated hydrocarbon (3). The disclosed method for producing a fluorinated hydrocarbon represented by formula (3) includes bringing into contact, in a hydrocarbon-based solvent, a secondary or tertiary ether compound represented by formula (1) below with an acid fluoride represented by formula (2) in the presence of lithium salt or sodium salt (in the formulae, R.sup.1 and R.sup.2 each represent a C.sub.1-3 alkyl, and R.sup.1 and R.sup.2 may be bonded to each other to form a ring structure; R.sup.3 represents a hydrogen atom, methyl, or ethyl; and R.sup.4 and R.sup.5 each represent methyl or ethyl). ##STR00001##

Provided is a method for industrially advantageously producing a fluorinated hydrocarbon (3). The disclosed method for producing a fluorinated hydrocarbon represented by formula (3) includes bringing into contact, in a hydrocarbon-based solvent, a secondary or tertiary ether compound represented by formula (1) below with an acid fluoride represented by formula (2) in the presence of lithium salt or sodium salt (in the formulae, R.sup.1 and R.sup.2 each represent a C.sub.1-3 alkyl, and R.sup.1 and R.sup.2 may be bonded to each other to form a ring structure; R.sup.3 represents a hydrogen atom, methyl, or ethyl; and R.sup.4 and R.sup.5 each represent methyl or ethyl). ##STR00001##

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.