Reference of 404337-42-4, A common heterocyclic compound, 404337-42-4, name is 5-Chloro-2-iodo-m-xylene, molecular formula is C8H8ClI, 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.
To a 250 mL vessel equipped with a mechanical stirrer, thermometer, distillation head anddropping funnel, solid sodium hydroxide (3.9 g, 0.10 mol, microprills with 0.5- 1 mm diameter) is chargedunder an inert atmosphere.1-Methyl-2-pyrrolidone (NMP, 68 g) is added to the vessel in one portion through the dropping funnel and the reaction mixture cooled to 10 – 15 C while stirring. A solution of malononitrile (NEC-CH2- CEN) (2.27 g, 0.034 mol) in NMP (2.7 g) is added through the dropping funnel over 5 minutes maintainingthe temperature at 10 – 15 C. The reaction mixture is then heated to 100 C and a vacuum (30 mbar) applied, upon which solvent (32 g) is distilled off. The mixture is then heated to 130 C and a stream of nitrogen is passed through.2-lodo-5-chloro-1 ,3-dimethyl-benzene (9.0 g, 95% purity, 0.032 mol) is then added through the dropping funnel over 5 minutes at 130 CC. A mixture containing palladium (II) chloride (0.150 g, solutionin conc. hydrochloric acid, assay 20% Pd, 0.281 mmol), triphenylphosphine (0.186 g, 0.709 mmol) and NMP (13.7 g) is then added through the dropping funnel over a 2-minute period. The temperature is allowed to rise to 130 C and the reaction mixture stirred at this temperature for 80 mm. Conversion is monitored by pulling samples and subsequent HPLC analysis. A second portion of a mixture containing palladium (II) chloride (0.103 g, solution in conc. hydrochloric acid, assay 20% Pd, 0.194 mmol),triphenylphosphine (0.132 g, 0.504 mmol) and NMP (9.76 g) is then added through the dropping funnel over a 2-minute period and the reaction mixture stirred at 130 C for 40 mm.When conversion is complete, a vacuum (20 – 40 mbar) is applied and solvent (38 g) is distilled off. The resulting residue is cooled to 80 C and water (30 g) is added. After cooling to room temperature, the resulting mixture is filtered through a filter paper and the filter cake washed with water (10 g). To thecombined filtrates, hydrochloric acid (9.6 g, assay 32%, 0.084 mol) is added to adjust the pH from 13.3 to 1.3.The resulting mixture is extracted with toluene (50 g). The organic phase is washed with water (2 x 20g) and evaporated to dryness. The resulting solid residue is recrystallized from 1-pentanol (17 g) and the resulting crystals filtered, washed with 1-pentanol (4 g) and dried under vacuum to yield 2-(4-chloro-2,6-dimethyl-phenyl)propanedinitrile (melting point (m.p.) 145 – 147 C).
The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.
Reference:
Patent; SYNGENTA PARTICIPATIONS AG; ZELLER, Martin; FEDOU, Nicolas; (19 pag.)WO2018/15489; (2018); A1;,
Iodide – Wikipedia,
Iodide – an overview | ScienceDirect Topics – ScienceDirect.com