Reference of 314084-61-2, These common heterocyclic compound, 314084-61-2, name is 2-Bromo-1,3-diethyl-5-methylbenzene, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.
a) Under a nitrogen atmosphere and at normal pressure, 7 g of malonic acid dinitrile dissolved in 3.5 ml of 1-methyl-2-pyrrolidone are added dropwise in the course of 30 minutes, at from 20 to 30C, to a mechanically stirred mixture of 12 g of sodium hydroxide (pellets) in 150 ml of dimethyl sulfoxide. Evacuation to from 10 to 30 mbar is carried out, and 79.1 g of solvent are distilled off at from 80 to 100C. After establishing normal pressure, 24 g (content 94.9%) of 2-bromo-1, 3-diethyl-5-methylbenzene are added, and the reaction mixture is heated to 130C. At that temperature, a mixture of 0.13 g of TRIPHENYLPHOSPHINE, 0.1 g of a commercially available palladium (II) chloride solution in concentrated hydrochloric acid (20% Pd content corresponding to 0.035 g of palladium (li) chloride in 0.071 g of concentrated hydrochloric acid) and 9.6 g of 1-methyl-2-pyrrolidone is added. The reaction mixture is stirred for from 2 to 3 hours at from 125 to 140C. A further 59.5 g of solvent are distilled off at from 20 to 60 mbar. 1.5 g of Hyflo and 75 ml of water are added to the residue which has been cooled to 50C. The reaction mixture is stirred vigorously for 10 minutes and then clarified by filtration over Hyflo. The filter is then washed with 50 ml of water. 23.3 g of 32% hydrochloric acid are added to the filtrate in the course of from 60 to 80 minutes, at from 20 to 25C, during the course of which the product crystallises out and the pH value falls to from 4.0 to 4.5. Suction filtration is carried out, followed by washing with 100 ml of water (divided into 2 portions). The product is dried in a vacuum drying cabinet for 16 hours at from 100 to 250 mbar. 20.6 g (content 97.9% ; yield 95. 1%) of 2- (2, 6-diethyl-4-methylphenyl) malonic acid dinitrile are obtained.
The synthetic route of 314084-61-2 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; SYNGENTA PARTICIPATIONS AG; WO2004/50607; (2004); A1;,
Bromide – Wikipedia,
bromide – Wiktionary