4-chloro-5-iodo-2-methylphenyl ethyl carbonate synthesis

Yield:930298-26-3 83%

Reaction Conditions:

Stage #1: carbonic acid 5-amino 4-chloro-2-methyl-phenyl ester ethyl esterwith hydrogenchloride;acetic acid;sodium nitrite in water at 0 - 5; for 0.5 h;
Stage #2: with iodine;potassium iodide in water at 20; for 1.5 h;

Steps:

27.4

Carbonic acid 5-Amino 4-chloro-2-methyl-phenyl ester ethyl ester (5.48 g) was dissolved in acetic acid (45 m) and the mix cooled to 0 ⁰C. 6N HCI (15 ml) was added giving a suspension. To this suspension was added sodium Nitrite solution (1.96 g in 16.6 ml water) drop-wise such that internal temp remained less than 5 ⁰C. When addition was complete mixture was stirred at 0 ⁰C for 30 minutes and then poured into and aqueous solution of potassium iodide (5.5 g) and iodine (1.8 g). Mixture was stirred for 90 mins at ambient temperature. Water (40 ml) was added and mix extracted with dichloromethane (3 times). Combined organics were washed with sodium thiosulphate solution (10% w/v), then sat. NaCI (aq) solution and dried over MgSO₄. Mixture was filtered and filtrate solvents removed in vacuo to afford product as a brown solid. (6.67 g, 83%).

References:

WO2007/34185,2007,A1 Location in patent:Page/Page column 45