Trifluoroacetaldehyde N-tosylhydrazone used as a precursor for the in situ generation of CF3CHN2 by treatment with weak bases in safe concentration underwent [3+2] cycloaddition to electron deficient alkenes in the presence of N,N-diisopropylethylamine to give 5-(trifluoromethyl)pyrazolines in high yields. The reaction proceeded under mild conditions, tolerated a wide range of the substituents, and gave products promising
三
氟乙醛N-
甲苯磺酰腙用作通过安全浓度的弱碱处理原位生成CF 3 CHN 2的前体,在
N,N-二异丙基乙胺存在下与缺电子烯烃进行[3+2]环加成,得到5- (三
氟甲基)
吡唑啉的产率很高。该反应在温和的条件下进行,可耐受多种取代基,并产生了有希望用于药物设计的产品。精心设计的程序避免了与使用CF 3 CHN 2相关的缺点,如挥发性、毒性和爆炸危险。