3,4-Diaryl-4,5-dihydro-1H-pyrazole compounds having a selected 5- or 6-membered aromatic heterocyclic moiety in the 4-position and an optionally substituted phenyl moiety in the 3-position, such as 4,5-dihydro-3-(4-fluorophenyl)-4-(5-trifluoromethyl-2-pyridinyl)-1H-pyrazo le were prepared as intermediates in the preparation of insecticidal 3,4,N-triaryl-4,5-dihydro-1H-pyrazole-1-carboxamide compounds. The 3,4-diaryl-4,5-dihydro-1H-pyrazole compounds can be prepared from appropriate 1,2-diarylethanone compounds by successive treatments with N,N,N',N'-tetramethyldiaminomethane in dichloromethane in the presence of acetic anhydride (to form a Mannich adduct) and hydrazine in the presence of a catalytic amount of trifluoroacetic acid.
含有选择的5-或6-成员芳香杂环基团的3,4-二芳基-4,5-二氢-1H-
吡唑烷化合物,在4位具有选择的5-或6-成员芳香杂环基团,在3位具有可选择取代的苯基基团,例如4,5-二氢-3-(4-
氟苯基)-4-(5-三
氟甲基-2-
吡啶基)-1H-
吡唑烷被制备为杀虫3,4,N-三芳基-4,5-二氢-1H-
吡唑烷-1-羧酰胺化合物的中间体。这些3,4-二芳基-4,5-二氢-1H-
吡唑烷化合物可以通过适当的1,2-二芳基乙酮化合物经过连续处理与
二氯甲烷中的N,N,N',N'-四甲基二
氨甲烷在
乙酸酐存在下(形成Mannich加合物)和在
三氟乙酸的催化下与联
氨反应制备。