121-86-8Relevant articles and documents
A practical synthesis of 2,4-dichloro-3-methyl-6-nitrophenol
Ran,Pittman Jr.
, p. 2785 - 2795 (1993)
2,4-Dichloro-3-methyl-6-nitrophenol 2 was prepared by KOH/H2O hydrolysis of a product mixture obtained from chlorination of p-nitrotoluene in the presence of a phase transfer catalyst. A 95-99% yield of 2 based on 2,3,6-trichloro-4-nitrotoluene, 4 (major chlorination product) was achieved in >95% purity.
Novel preparation method of mosapride
-
Paragraph 0033-0036, (2021/08/07)
The invention discloses a novel preparation method of mosapride.Cheap 2-chlorotoluene is used as an initial raw material is subjected to nitration, nucleophilic substitution, free radical bromination, chlorination, alkylation, nitro reduction and oxidative amidation to synthesize mosapride. According to the scheme, raw materials are easy to obtain, dangerous processes and highly toxic reagents are avoided, the method is green and environment-friendly, oxidation amidation is adopted, selectivity is achieved, formation of aromatic amide by-products is avoided, and the yield is high.
O-chlorotoluene catalytic nitration method by using microwaves for assisting zeolite
-
Paragraph 0024-0045, (2018/11/03)
The invention discloses an o-chlorotoluene catalytic nitration method by using microwaves for assisting zeolite. The method comprises the following steps of adding solvents into a container; sequentially adding o-chlorotoluene, acetic anhydride, nitrosonitric acid, modified zeolite molecular sieve catalysts and silicon dioxide loaded perfluorinated sulfonic acid resin; performing microwave temperature rise for 4 to 12min; performing heat insulation for 8 to 10min; terminating the reaction. The microwave technology is applied to the o-chlorotoluene nitration process; the reaction progress is greatly accelerated; meanwhile, silicon dioxide is used for loading perfluorinated sulfonic acid resin; the perfluorinated sulfonic acid resin is dispersed into SiO2 networks or pore passages; the effective surface area is greatly increased, so that the acid positions of the perfluorinated sulfonic acid resin are sufficiently exposed, so that the potential of the resin catalyst is achieved; the conversion rate and the yield are improved; in addition, the modified zeolite molecular sieve catalyst Bibeta provides acid centers and pore passage structures; the shape selection catalyst effect is provided; the reaction selectivity is improved; the yield is as high as 80.9 percent; the selectivity of the 2-chloro-4-nitrotoluene is as high as 84.1 percent. The method has the advantages that the operation is easy; the energy is saved; the efficiency is high; the control is easy; the method belongs to a green and environmental-friendly o-chlorotoluene nitration method.