4- Iodo-l-methylpyrazole-5 -carboxylic

The cyclocondensation of 4-iodo-l-methylpyrazole-5-carboxylic acid with PhC=CCu under similar conditions is over in 1.5 h. Thus, the cyclization of the... 

The cyclocondensation of 4-iodo-l-methylpyrazole-5-carboxylic acid with PhC CCu under similar conditions is over in 1.5 h. Thus, the cyclization of the 4-phenylethynyl-l-methylpyrazole-5-carboxylic acids and the cyclocondensation of the iodine acid with PhC CCu give the same products pyranopyrazoles. However, the formation rate of the first reaction is much higher. 

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