Regioselective Synthesis of Pyrazole Triflones Based on Triflyl Alkyne Cycloadditions
作者:Hiroyuki Kawai、Zhe Yuan、Etsuko Tokunaga、Norio Shibata
DOI:10.1021/ol3025154
日期:2012.10.19
The regioselective synthesis of pyrazole triflones has been achieved by 1,3-dipolar cycloaddition of triflyl alkynes and hydrazonoyl chloride in the presence of Hünig’s base. Pyrazolo[5,1-a]isoquinoline triflones were also regioselectively synthesized for the first time via tandem 1,3-dipolar cycloaddition/oxidative aromatization between triflyl alkynes and C,N-cyclic azomethine imines.
在Hünig碱的存在下,通过三氟乙炔和酰氯的1,3-偶极环加成反应可实现吡唑三氟酮的区域选择性合成。吡唑并[5,1- a ]异喹啉三氟甲磺酸还通过三氟乙炔与C,N-环偶氮甲亚胺之间的串联1,3-偶极环加成/氧化芳构化而首次区域选择性合成。