Yield:109418-89-5 39%

Reaction Conditions:

with hydrogenchloride;zinc(II) chloride in water at 50; for 21 h;Blanc Chloromethylation Reaction;

Steps:

1.a.1

A mixture of 2-chlorothioanisole (200 g, 1.26 mol, 1.00 eg.), paraformaldehyde (126 g, 4.20 mol, 3.33 eg.), ZnCl₂ (75.6 g, 0.55 mol, 0.44 eg.) and hydrochloric acid (630 ml, 37% in H₂O) was stirred at 50⁰C for 21 h. The organic phase was removed, washed with water and distilled, which removed unconverted 2- chlorothioanisole (82.4 g, 0.52 mol, 41%). The remaining distillation bottoms consisted for the most part of 3-chloro-4-methylthiobenzyl chloride (123.6 g, purity 83.2% (HPLC), 0.50 mol , yield 39%) and were used directly in the next step. It was also shown that it is possible to increase the purity of this substance further by distillation of 3 -chloro-4-methylthiobenzyl chloride (purity: 98.3 a% (GC)).

References:

WO2007/96034,2007,A1 Location in patent:Page/Page column 10-11