Environmentally Benign Synthesis of 2,3-Unsaturated Glycopyranosides in Task-Specific Ionic Liquid

Abstract

A green reaction condition has been developed for the synthesis of 2,3-unsaturated glycopyranosides by the Ferrier rearrangement of glycals using alcohols and thiols in 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([BMIM]ÁOTf) in excellent yield.[BMIM]ÁOTf has been applied as a task specific ionic liquid organo-catalyst. Operational simplicity, environmentally benign reaction condition, use of task specific ionic liquid, short reaction time, high yields are the notable features of this methodology.

Recent Developments in the Ferrier Rearrangement

“…Along similar lines, Schmidt and co‐workers designed glycals with C3‐trichloroacetimidate leaving groups and studied their behavior in Lewis‐acid‐catalyzed glycosylations 93. In fact, when trichloroacetimidate derivative 87 (Table 9) was treated with alcohols in the presence of trimethylsilyl triflate94 the corresponding 2,3‐unsaturated galactosides were obtained in excellent yields 95. The reactions also proved to be highly stereoselective, yielding α‐anomers exclusively.…”

“…Lewis acids have been widely used to effect Ferrier rearrangement with thiols and glycals during the last decade. They include 1‐butyl‐3‐methylimidazolium trifluoromethanesulfonate ([BMIN] · OTf),94 iodine,214 AuCl 3 ,72 InCl 3 ,215 La(NO 3 ) 3 · 6 H 2 O,84 Er(OTf) 3 ,76 NbCl 5 ,71a ZrCl 4 ,156 and Sc(OTf) 3 216. However, the current tendency in Ferrier rearrangement with thiols and glycals seems to be toward the use of heterogeneous or supported catalysts.…”

One-pot resource-efficient synthesis of SnSb powders for composite anodes in sodium-ion batteries

“…Another major goal of conducting environmentally-friendly chemistry is to maximize the efficient use of raw materials and simultaneously to minimize waste. 32,33 Therefore, the synthetic route has to address not only yield and purity of the nal product but also the atom economy.…”

Recent Advances in C-Glycoside Chemistry: Application, Synthesis and Reactions

“…Os C-glicosídeos estão envolvidos em diversos papéis importantes nos organismos vivos, tais como fonte de energia, na etapa de crescimento da planta atuando na regulação e estimulante muscular cardíaco. 1 Dentre as diferentes classes de carboidratos um grande destaque é dado para os glicais, 2 os quais são largamente utilizados na síntese dos mais diversos tipos de O-glicosídeos, [3][4][5][6][7][8][9][10] C-glicosídeos, [11][12][13][14][15][16][17][18] Sglicosídeos, [19][20][21][22][23][24][25][26][27] N-glicosídeos [28][29][30][31][32][33][34][35] e vários tipos de oligossacarídeos (Figura 1); 36 além de serem utilizados como blocos de construção para síntese de 2-desoxi-hexoses e 2-desoxi-2amino-hexoses e na síntese de produtos naturais oticamente ativos. 37…”