Extracurricular laboratory: Synthetic route of 21740-00-1

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.

Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 21740-00-1, name is 5-Bromo-2-iodobenzoic acid, A new synthetic method of this compound is introduced below., COA of Formula: C7H4BrIO2

C. N, N-DIMETHYL-5-BROMO-2-IODOPHENYLACETAMIDE 5-Bromo-2-iodobenzoic acid (100 g, 0.306 mol) is dissolved in THF (350 mL) and cooled in an ice bath. Borane-THF complex (460 mL of 1 M in THF, 0.460 mol) is added dropwise. After addition is complete, the reaction is warmed to room temp and stirred for 14 hours. The mixture is transferred a large ERLENMEYER FLASK (4 L), cooled in an ice bath and carefully quenched with water (250 mL). Evaporation of the THF by rotary evaporator gives a white suspension which is treated with additional water (1 L) and then filtered and dried in a vacuum dessicator over P205 to give 5-bromo-2-iodobenzyl alcohol. The above benzyl alcohol is dissolved in 48% HBr (500 mIL and heated at reflux temperature for 4 hours. The resulting benzyl bromide is isolated as a yellow solid by pouring the cooled mixture into a large volume (1.5 L) of water followed by filtration. The benzyl bromide is dissolved in EtOH (400 mL) and stirred at room temperature. Sodium cyanide (56 g, 1.14 mol) is dissolved in a minimum amount (-100 mL) of water and then added to the ethanolic solution of the benzyl bromide. The reaction is heated to reflux temperature for 3 hours and then cooled to room temperature. Ethanol is removed by rotary evaporator and the residue washed with a large volume (1 L) of water. The resulting 5-bromo-2-iodophenylcetonitrile is isolated by filtration. The above phenylacetonitrile is dissolved in ETOH (350 mL) and treated with NAOH (32 g, 0.8 mol) which had been dissolved in water (200 mL). The reaction is heated at reflux temperature for 14 hours. After cooling to room temperature, ethanol is removed by rotary evaporator and 6 N HCI added until the pH = 1. The solid 5-bromo-2-iodophenylacetic acid that formed is filtered and washed with water (2 x 500 mL). After drying over P205 in a vacuum dessicator, 5-BROMO-2-IODOPHENYLACETIC acid (m. p. 165-169C) (102 g, 0.3 mol) is dissolved in CH2CI2 (450 mL) that contains several drops of DMF. Thionyl chloride (32 mL, 0.450 mol) is added and the reaction heated to reflux temperature overnight. After cooling to room temperature, the reaction mixture is diluted with additional CH2CI2 (500 mL) and washed with water (2 x 250 mL), saturated NAHCO3 (250 mL) and brine (250 mL). The solution is dried (MGS04) and concentrated by rotary evaporator to give 5-bromo-2- iodophenylactetyl chloride as a yellowish oil. Dimethylamine (200 mL of 2 M in THF) is added dropwise to a solution of the above 5-bromo-2-iodophenylacetyl chloride in ET20 (500 mL), cooled in an ice bath. After the addition is complete, EtOAc (350 mL) is added and the solution washed with water (350 mL), brine (250 mL) and dried (MGS04). Evaporation by rotary evaporator and trituration with 1: 1 ET2O/HEXANES GIVES N, N-DIMETHYL-5-BROMO-2-IODOPHENYLACETAMIDE (m. p. 127-129C).

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; NOVARTIS AG; NOVARTIS PHARMA GMBH; WO2004/48314; (2004); A1;,
Iodide – Wikipedia,
Iodide – an overview | ScienceDirect Topics – ScienceDirect.com