在3,5-dibromo-1反应中合成了1-(1,1-Dioxidothietan-3-yl)-1 H-咪唑和1-(1,1-dioxidothietan-3-yl)-1 H-苯并咪唑-(1,1-二氧噻吩-3-基)-1 H -1,2,4-三唑与咪唑和苯并咪唑的钠盐。该反应涉及将唑类添加到就地形成的1,1-二氧化噻吩中,该噻吩充当迈克尔受体。显示了咪唑和苯并咪唑的p K a值对其反应性的影响。
A novel protecting group for NH functionality of heterocycles, a thietane ring, was proposed. It can be readily introduced by alkylation of NH-heterocycles with 2-chloromethylthiirane. Removal of the thietane protecting group is performed via oxidation to thietane 1,1-dioxide with hydrogen peroxide in acetic acid and subsequent treatment with sodium alkoxide.
Dioxothietanylation of Heterocycles 1. N-(1,1-Dioxothietan-3-yl)-1,2,4-triazoles
作者:E. E. Klen、N. N. Makarova、F. A. Khaliullin
DOI:10.1007/s10593-013-1159-7
日期:2013.1
3,5-Substituted 1-(1,1-dioxothietan-3-yl)-1,2,4-triazoles have been prepared by treating NH-1,2,4-tri-azole sodium salts with 3,5-dibromo-1-(1,1-dioxothietan-3-yl)-1,2,4-triazole (a novel dioxothietanylating reagent). The reactions occur regioselectively at the position 2 for 5-bromo-1,2,4-triazoles containing ethoxy-, isopropoxy-, or phenoxy groups at the position 3 and at position 1 for 3-methylsulfanyl-1,2,4-tri-azole. The reaction occurs nonselectively at positions 1 and 2 in the case of 3-methylsulfonyl-1,2,4-tri-azole and 5-bromo-3-(piperidin-1-yl)-1,2,4-triazole, to give the isomeric 3-R-5-R-1- and 5-R-3-R-1-1-(1,1-di-oxothietan-3-yl)-1,2,4-triazoles.