Iodine → 1,2-Di-p-tolylethane

Participants

Reaction Steps

200 ml of anhydrous tetrahydrofuran (THF), 3.35 g (0.138 mol) of Mg turnings and a crystal of I2 were placed in a 500-ml three-necked round-bottomed flask equipped with a 100-ml dropping funnel, thermometer and reflux condenser. Then a solution of 35.15 g (0.25 mol) of α-chloro-p-xylene in 50 ml of anhydrous THF was added drop by drop. Heating was required to start the reaction, then self-heating was observed. After 3 hours, all of the Mg had dissolved. The reaction mixture was kept under reflux for 3 hours, then left to rest for one night. All the THF was evaporated at reduced pressure and the residue was treated with a mixture of 150 ml of hexane and 150 ml of 10% HCl. The organic phase was separated, washed with aqueous NaCl (3 times) and dried over Na2SO4. After evaporating the solvent, white crystals were isolated, and these were dried under vacuum at 70° C. 24.3 g of 1,2-di-p-tolylethane was obtained (yield: 92.4%).

Provenance & Evidence