トシルオキシムからジアジリン合成における液体アンモニアがはたす 2

トシルオキシムからジアジリン合成における液体アンモニアがはたす
２つの役割の検討
Dual role of liquid NH3 in direct construction of
diazirines from tosyloximes
王磊, 橋床泰之, 橋本誠 (北大院農)
3-(Trifluoromethyl)-3-phenyldiazirine (TPD) has emerged as the most effective photoreactive group in
photoaffinity labeling because of its thermal and chemical stability, long activation wavelength, low rate of
rearrangement, high reactivity of the intermediate. Otherwise, the tedious synthetic procedure of TPD
derivatives is a major consideration for researchers. For many decades, preliminary construction of
diaziridine under liquid NH3 and further conversion to TPD in the presence of oxidants are the inevitable
steps for preparation of TPD derivatives (A). During the process, the isolation of diaziridines, preparation
of fresh oxidant, and post-treatment after oxidation were time-consuming and yield-diminishing which
significantly limit the application of TPD derivatives in photoaffinity labeling.
We developed novel direct syntheses of TPD derivatives from corresponding tosyloximes (B).1
Formation of TPD from tosyloxime was achieved in the presence of liquid NH3 at 80 C without any
additives. Comprehensive investigation indicated that liquid NH3 played a dual role for construction of
TPD from tosyloxime. Initially, NH3 molecule attacks tosyloxime to form gem-diamine intermediate. With
the removal of tosyl group and one proton, diaziridine is formed. Next, the NH2- generated from liquid NH3
triggers deprotonation of diaziridine ring following with the formation of TPD along with hydrogen and
NH3. In this procedure, liquid NH3 acts not only the direct regent for construction of diaziridine but also the
precursor of NH2- as a novel species to afford TPD derivatives. For further application, an alternative
method was conducted at room temperature in the presence of LiNH2 as NH2- supplier. The alternative
one-pot methods significantly shorten the synthetic route of TPD derivatives2 in photoaffinity labeling.
Scheme. Construction of TPD derivatives from corresponding tosyloximes.
＜参考文献＞
1）Lei Wang, et al. Org. Lett. 2015, 17, 616–619.
2）Lei Wang, et al. Eur. J. Org. Chem. (accepted).
発表者紹介
氏名
王磊（Wang
所属
農学研究院応用生物科学専攻
学年
DC 2
研究室
生態化学生物学研究室
Lei）

Download Report