31 results about "2-methylbenzoic acid" patented technology

The invention discloses a method for preparing lenalidomide. The method uses 3-amino-2-methylbenzoic acid as a starting material to synthesize lenalidomide. The method for preparing lenalidomide of the present invention can effectively prepare lenalidomide, and the process is simple, the synthesis efficiency is high, and the purity of the prepared lenalidomide is high. In addition, the preparation method also has the advantages of easy availability of starting materials, simple process operation, mild reaction conditions, no need for special reaction equipment, and no difficult-to-separate compounds in the preparation process, so it is more suitable for large-scale and industrial production of lenalidomide .

The present invention provides a process for producing 5-iodo-2-methylbenzoic acid through iodination of 2-methylbenzoic acid, the process including, as essential steps, a reaction step of iodinating 2-methylbenzoic acid in the presence of a microporous compound, iodine, an oxidizing agent, and acetic anhydride, and a purification step including sublimation, distillation, crystallization, or a combination of two or more of these. According to the present invention, 5-iodo-2-methylbenzoic acid, which is useful for producing functional chemicals such as drugs, can be produced at high purity and high yield in a simple manner. Since the production process includes a simple reaction step and a simple separation / purification step, the load of purification is mitigated. In addition, the microporous compound such as a zeolite catalyst which has been separated and recovered from the reaction mixture can be repeatedly employed after performing of a simple treatment. Thus, the production process ensures a long service life of catalysts and high efficiency.

Herein disclosed is a method, comprising: forming a dispersion under high shear comprising gas bubbles of an oxidant dispersed in a liquid phase, wherein the bubbles have a mean diameter of less than 1.5 micron; and contacting the dispersion with an oxidation catalyst to produce a product stream, wherein the product stream comprises a substance selected from the group consisting of dicarboxylic acid, benzoic acid, 2-methylbenzoic acid, 3-methylbenzoic acid, 4-methylbenzoic acid, and phthalic anhydride. In some cases, forming the dispersion under high shear comprises introducing the oxidant and the liquid phase into a high shear device comprising at least one rotor and at least one complementarily-shaped stator. Herein also disclosed is a system for producing a substance selected from the group consisting of dicarboxylic acid, benzoic acid, 2-methylbenzoic acid, 3-methylbenzoic acid, 4-methylbenzoic acid, and phthalic anhydride.

The invention discloses a preparation method of 4,5-dihydroxyl-2-methyl benzoic acid and belongs to the fields of fine chemical engineering and medicine intermediates. The preparation method of 4,5-dihydroxyl-2-methyl benzoic acid comprises the following steps: preparing an intermediate III or V by taking 4-methylbenze-1,2-diphenol as a raw material, then preparing an intermediate IV by virtue of the intermediate III or V, then transforming the intermediate IV into an intermediate II, and finally preparing 4,5-dihydroxyl-2-methyl benzoic acid by virtue of the intermediate II. The preparation method of 4,5-dihydroxyl-2-methyl benzoic acid has the advantage that the problems that raw materials are difficult to acquire, byproducts are many, yield is low, cost is high, steps are miscellaneous, safety can not be guaranteed and serious pollution is produced in the prior art are overcome.

The present invention provides a process for producing 5-iodo-2-methylbenzoic acid by iodizing 2-methylbenzoic acid, which comprises, as essential steps, a reaction step in which 2-methylbenzoic acid is iodized in the presence of a microporous compound, iodine, an oxidizing agent, and acetic anhydride and a purification step in which sublimation, distillation, crystallization, or a combination of two or more of these is conducted. By the process, 5-iodo-2-methylbenzoic acid, which is useful in functional chemicals such as medicines, can be easily obtained as a high-purity compound in a high yield. The production steps comprising reaction and separation / purification are simple from the standpoint of process operation and the purification load is small. Furthermore, the microporous compound, e.g., a zeolite catalyst, separated and recovered from the liquid resulting from the reaction can be repeatedly used after a simple treatment. Consequently, the catalyst has a long life and the target compound can be produced by the efficient process.

Provided is a production method for an iodine compound in which iodine is reacted with a substrate in the presence of a porous material having a pore diameter of 500 nm or less or in the presence of the above porous material and an oxidizing agent and a production process for high purity 5-iodo-2-methylbenzoic acid comprising an iodination reaction step carried out by the above-mentioned, a crystal precipitation and separation step in which a product is precipitated by adding water or cooling and then separated and a purification step in which crystal separated is recrystallized using an organic solvent. According to the production method for an iodine compound described above, iodine can be introduced into various substrates at a high selectivity. Since expensive metals and specific reagents do not have to be used, it can readily be carried out in an industrially scale, and the product having a high purity can be obtained. Further, the process comprising the iodination reaction, separation and purification steps described above makes it possible to readily obtain at a high yield, 5-iodo-2-methylbenzoic acid having a high purity which is useful in uses for functional chemical products such as medicines. The process of the present invention comprising iodination reaction, separation and purification steps is characterized by that it is simple in terms of a procedure and that the purification load is smaller, and it is very advantageous in industrially carrying out.

Provided is a production method for an iodine compound in which iodine is reacted with a substrate in the presence of a porous material having a pore diameter of 500 nm or less or in the presence of the above porous material and an oxidizing agent and a production process for high purity 5-iodo-2-methylbenzoic acid comprising an iodination reaction step carried out by the above-mentioned, a crystal precipitation and separation step in which a product is precipitated by adding water or cooling and then separated and a purification step in which crystal separated is recrystallized using an organic solvent. According to the production method for an iodine compound described above, iodine can be introduced into various substrates at a high selectivity. Since expensive metals and specific reagents do not have to be used, it can readily be carried out in an industrially scale, and the product having a high purity can be obtained. Further, the process comprising the iodination reaction, separation and purification steps described above makes it possible to readily obtain at a high yield, 5-iodo-2-methylbenzoic acid having a high purity which is useful in uses for functional chemical products such as medicines. The process of the present invention comprising iodination reaction, separation and purification steps is characterized by that it is simple in terms of a procedure and that the purification load is smaller, and it is very advantageous in industrially carrying out.