An efficient synthesis of 1-cyanoacetyl-5-halomethyl-4,5-dihydro-1H-pyrazoles in ionic liquid
作者:Dayse N. Moreira、Clarissa P. Frizzo、Kelvis Longhi、Nilo Zanatta、Helio G. Bonacorso、Marcos A. P. Martins
DOI:10.1007/s00706-008-0874-8
日期:2008.9
The synthesis of eleven 1-cyanoacetyl-5-hydroxy-5-halomethyl-4,5-dihydro-1H-pyrazoles from the reaction of 4-alkoxy-3-alken-2-ones f((RC)-C-3(O)C(R-2) = C(R-1)OR, where R-3 = CF3, CCl3, CHCl2, CO2 Et; R-2/R-1 = H/H, H/Me, H/Et, -(CH2)(4)-, Me/H, H/Pr, and R = Me, Et) with cyanoacetohydrazide is reported. The reaction was carried out in the ionic liquid ([bmim][BF4]) and molecular solvents. The results showed that when the ionic liquid was used as reaction medium, the reaction time was drastically decreased and the yield was improved.