SYNTHESIS AND THERMAL TRANSFORMATIONS OF SULFONYL-SUBSTITUTED 3,3,4AND 3,3,5-TRIPHENYL-3 H-PYRAZOLES |
| 4 | |
| 2013 |
| scientific article | 547.513 + 547.776 | ||
| 123-129 | (phenylethynyl)sulfone, diphenyldiazomethane, 1,3-dipolar cycloaddition, sulfonyl-substituted pyrazoles, thermolysis, cyclopropene, X-ray analysis (XRA). |
| Methyl- and p -tolyl(phenylethynyl)sulfones react with diphenyldiazomethane forming a double-component mixture of 1,3-dipolar cycloaddition products – sulfonyl-substituted 3 Н -pyrazoles on and against the Auwers rule in the ratio of 1:1.5 and 1.3:1, respectively. Under heating at reflux in toluene for 2 h, the products of the addition on the Auwers rule isomerize into corresponding 4 Н -pyrazoles. The products of the addition against the Auwers rule yield 1 Н -pyrazoles with admixture of the sulfonyl-substituted cyclopropenes under the same conditions. |
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