摘要:
Provided is a method of preparing and recovering 2-methyl-5-iodobenzoic acid. The method utilizes o-methylbenzoic acid as raw material, iodinating via iodine/potassium persulfate in a mixed acid solvent to obtain a mixture of 2-methyl-5-iodobenzoic acid, 2-methyl-3-iodobenzoic acid, and 2-methyl-3, 5-diiodobenzoic acid; refining to obtain 2-methyl-5-iodobenzoic acid and recoverable mother liquor, the recoverable mother liquor being a mixture of 2-methyl-5-iodobenzoic acid, 2-methyl-3-iodobenzoic acid, and 2-methyl-3, 5-diiodobenzoic acid; conducting catalytic hydrogenation and deiodination to recover o-methylbenzoic acid and iodide ions; and oxidating the iodide ions to recover iodine. The whole process is recycled. The preparation and recovery method has cheap and easily available raw materials, and is easy of operation, has low requirements for equipment, and is suitable for large-scale industrial production.
摘要:
The present invention discloses 5-bromo-2-(±-hydroxypentyl)benzoic acid sodium salt in different crystal forms and the preparation methods thereof, and belongs to the field of pharmaceutical chemistry. Said different crystal forms of 5-bromo-2-(±-hydroxypentyl)benzoic acid sodium salt include: amorphous 5-bromo-2-(±-hydroxypentyl)benzoic acid sodium salt, crystal form A of 5-bromo-2-(±-hydroxypentyl)benzoic acid sodium salt, and crystal form B of 5-bromo-2-(±-hydroxypentyl)benzoic acid sodium salt. The different crystal forms of 5-bromo-2-(±-hydroxypentyl)benzoic acid sodium salt obtained according to the present invention have better stability and water-solubility than the mixed forms of 5-bromo-2-(±-hydroxypentyl)benzoic acid sodium salt, thus is advantageous for pharmaceutical use. Moreover, the different crystal forms of 5-bromo-2-(±-hydroxypentyl)benzoic acid sodium salt possess much better therapeutic effect than 5-bromo-2-(±-hydroxypentyl)benzoic acid potassium salt.
摘要:
Provided is a simple, safe, and industrially practical method for producing a pentafluorosulfanylbenzoic acid. This method includes (A) a providing step of providing a trihalomethyl(pentafluorosulfanylbenzene) represented by general formula (1):
where X is a halogen atom, n is an integer of 1 ≤ n ≤ 3, and the hydrogen atoms on the benzene ring are optionally replaced with a group having an oxygen atom, a group having a nitrogen atom, or a halogen atom; (B1) a step of reacting the trihalomethyl(pentafluorosulfanylbenzene) with a carboxylic acid, water, or a disiloxane represented by general formula (b):
R 3 Si-O-SiR 3 (b)
(where R 3 is an alkyl group) in the presence of an acid other than carboxylic acids to form a pentafluorosulfanylbenzoic halide represented by general formula (2a):
where X and n are as defined above, and the hydrogen atoms on the benzene ring are optionally replaced with the group or atom defined above; and (B2) a step of converting the pentafluorosulfanylbenzoic halide into a pentafluorosulfanylbenzoic acid represented by general formula (2):
where n is as defined above, and the hydrogen atoms on the benzene ring are optionally replaced with the group or atom defined above.
摘要:
Organozinc salts and mixtures thereof, organozinc salt coated particles, methods of preparing organozinc salts and organozinc salt coated particles, and various applications of such coated particles, including applications in rubber, other polymeric materials, and pesticides and/or fungicides are disclosed. As compared to rubber formulations without organozinc salt, formulations with organozinc salts including the present coated particles may have lower Mooney viscosity and lower minimum torque, improved dispersability, a higher modulus at 100% and/or at 300% elongation, a higher tensile strength, better aging resistance, better abrasion resistance, and/or lower heat buildup. Thus, products containing the present coated particles may enjoy similar or better properties than comparative products that include a conventional filler and/or organozinc salts per se, and the present coated particles may result in cost savings for the corresponding product formulations. The need for a silane coupling agent may also be reduced or eliminated.
摘要:
A process for the production of iodine compounds by reacting iodine with a substrate either in the presence of a porous compound having a pore diameter of 500 nm or below or in the presence of such a porous compound and an oxidizing agent; and a process for the production of high-purity 5-iodo-2-methyl- benzoic acid which comprises the iodination step according to the above process, the crystallization/separation step of precipitating the reaction product either by the addition of water or by cooling and separating the precipitated crystalline substance, and the purification step of recrystallizing the crystalline substance from an organic solvent. According to the former process, iodine can be introduced into various substrates with high selectivity without using any expensive metal or any special reagent, so that the process can be easily carried out industrially and can give high-purity products. According to the latter process, 5-iodo-2-methylbenzoic acid useful in the field of functional chemicals such as drugs can be easily produced at high purity and in high yield. The processes are easy and simple and are characterized by small purification load and so on, thus being very advantageous to carry out industrially.