M. Palucki, Zhihao Lin, Yong-kui Sun
Jan 15, 2005
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0
Influential Citations
11
Citations
Journal
Organic Process Research & Development
Abstract
2-Chloro-N,N-dimethylamino trimethinium chloride salt (CDT-chloride) is a key intermediate in the synthesis of Etoricoxib, a selective COX-2 inhibitor developed by Merck & Co., Inc. The formation of CDT-chloride from a mixture of chloroacetic acid and POCl3 in DMF was monitored by in situ IR and in situ NIR. The buildup of transient intermediates, starting material disappearance, and product/byproduct formation were effectively followed during the course of the reaction using both techniques. The observations confirmed the intermediacy of both chloroacetyl chloride and a Vilsmeier type reagent as well as document the evolution of carbon dioxide.