185244-97-7

Upstream product

• 21613-46-7 (2E,3E)-4-(4-methoxyphenyl)but-3-en-2-one oxime 
• 68-12-2 N,N-dimethyl-formamide 
• 18797-94-9 N-[(1E)-2-(4-methoxyphenyl)ethenyl]acetamide 

Downstream Products

• 1205671-65-3 [2-chloro-5-(4-methoxyphenyl)-3-pyridyl]methanol 

Relevant academic research and scientific papers

Facile and selective synthesis of chloronicotinaldehydes by the Vilsmeier reaction

Eleven enamides were prepared by adopting different procedures. The various enamides prepared were subjected to Vilsmeier reaction using (i) POCl3/DMF; (ii) diphosgene/DMF; (iii) triphosgene/DMF leading to the formation of various multisubstituted chloronicotinaldehydes. Studies carried out indicate that Vilsmeier reagent concentration and the replacement of POCl3 by diphosgene or triphosgene, provides excellent selectivity and higher yields. Under modified reaction conditions one can get only chloronicotinaldehydes and not the chloropyridines as products. The various advantages in using diphosgene and triphosgene are illustrated. The mechanism of formation of chloronicotinaldehyde was discussed.

A novel route to the synthesis of 3-pyridine carboxaldehydes by Vilsmeier reagent

2-Chloro-5-aryl-3-pyridine carboxaldehydes are obtained by Vilsmeier reaction of 4-aryl-3-buten-2-one oxime. The suspected intermediate N-(2- arylethenyl)acetamides also give the same 2-chloro-5-aryl-3-pyridine carboxaldehydes under identical reaction condition.