216084-90-1

Upstream product

• 64-18-6 formic acid 
• 97693-26-0 2-hydrazino-1-methyl-6-oxo-4-phenyl-1,6-dihydropyrimidine-5-carbonitrile 
• 122-51-0 orthoformic acid triethyl ester 
• 95534-78-4 1-methyl-2-(methylthio)-6-oxo-4-phenyl-1,6-dihydropyrimidine-5-carbonitrile 
• 97693-21-5 2-methylsulfanyl-6-oxo-4-phenyl-1,6-dihydropyrimidine-5-carbonitrile 

Relevant academic research and scientific papers

Reaction of pyrimidinonethione derivatives: Synthesis of N-methyl-2-hydrizinopyrimidine-4-one, thiazolo[3,4-b] N-methylpyrimidinone; 2-(1-pyrazolonyl) N-methylpyrimidine-4-one and 2-hydrazino-N-methyl pyrimidine-4-one derivatives

6-Aryl-5-cyano-4-pyrimidinone-2-thion derivatives 1a-c reacted with methyl iodide (1:2) to give the corresponding 2-S,N-dimethyl pyrimidine-4-one derivatives 2a-c. Compounds 2a-c were in turn, reacted with hydrazine hydrate to give the sulfur free reaction products 3a-c. These reaction products were taken as the starting materials for the synthesis of several new heterocyclic derivatives. Reaction of 3a-c with acetic anhydride and formic acid gave pyrimido triazines 4a-c and 7a-c, respectively. Their reactions with active methylene containing reagents gave the corresponding 2-(1-pyrazonyl)-N-methyl pyrimidine derivatives 9a-c and 10a-c, respectively. Their reactions with aromatic aldehydes afforded the corresponding 2-hydrazono pyrimidine derivatives 11a-c. The structure of these reactions products were established based on both elemental analysis and spectral data studies.

Synthesis and Dimroth rearrangement of 6-cyano-1,2,4-triazolo-[4,3-a]pyrimidin-5- and 7-ones. A novel alkylation with orthoesters and a new participation of the cyano group in the rearrangement

The cyclization products of 5-cyano-2-hydrazino-6-phenyl-3,4-dihydropyrimidin-4-one (6) with one carbon inserting agents have been confirmed to be of the 1,2,4-triazolo[4,3-a]pyrimidin-5(8H)-ones type and not the respective 7-ones, by comparing their alkylated derivatives 10a, 11a, 27 and 28 with the product from the cyclization of the 3-methyl and 3-benzyl derivatives of 6. A novel alkylation process was found when triethyl orthoformate was used as a cyclizing agent. Dimroth rearrangement of 8, 14, 15, 24, 34 and 36 with 2% ethanolic KOH gave the respective triazolo[1,5-a]pyrimidinone 13, 18, 19, 25, 38 and 40, respectively. Using 10% ethanolic KOH led to a novel participation of the cyano group in the rearrangement whereby 8a gave 7-imino-5-phenyl-1,2,4-triazolo[1,5-a]pyrimidine 22.