61893-77-4Relevant academic research and scientific papers
Reactions of some 2- and 4-O-triflylglycopyranosides with MeLi, t-BuOK, and pyridine
El Nemr, Ahmed,Tsuchiya, Tsutomu
, p. 205 - 214 (2007/10/03)
As an extension of our previous work on secondary triflates of carbohydrates [El Nemr, A.; Tsuchiya, T. Tetrahedron Lett. 1995, 36, 7665-7668. El Nemr, A.; Tsuchiya, T.; Kobayashi, Y. Carbohydr. Res. 1996, 293, 31-59. El Nemr, A.; Tsuchiya, T. Carbohydr. Res. 1997, 301, 77-87. El Nemr, A.; Tsuchiya, T. Carbohydr. Res. 1997, 303, 267-281], the reaction modes of several methyl 2- and 4-O-triflyl-D-glycopyranosides with MeLi (strong base), t-BuOK (moderately strong base), and pyridine (weak base) have been studied. This paper describes the reactions of 3-O-benzyl-4,6-O-benzylidene-2-O-triflyl-D-gluco and -mannopyranosides with MeLi to give mainly the corresponding 2-C-methyl derivatives through α-elimination, with t-BuOK to give either the 2,3-unsaturated compounds through β-elimination or detriflyl 2-ols, and with hot pyridine to give the corresponding 2-pyridinium salts with inversion (except for the 2-O-triflyl-α-D-mannopyranoside (8)). 2,3,6-Tri-O-benzyl-4-O-triflyl-α-D-gluco and -mannopyranosides were also examined similarly.
Design and reactivity of organic functional groups - Preparation and nucleophilic displacement reactions of imidazole-1-sulfonates (imidazylates)
Vatele, Jean-Michel,Hanessian, Stephen
, p. 10557 - 10568 (2007/10/03)
Imidazole-1-sulfonate, a new type of leaving group by remote activation, allows facile S(N)2 substitution reactions at sterically crowded centers with various nucleophiles under mild conditions. It could be easily prepared from alcohols with cheap reagent
DESIGN AND REACTIVITY OF ORGANIC FUNCTIONAL GROUPS: IMIDAZOLYLSULFONATE (IMIDAZYLATE) - AN EFFICIENT AND VERSATILE LEAVING GROUP
Hanessian, Stephen,Vatele, Jean-Michel
, p. 3579 - 3582 (2007/10/02)
The preparation and reactivity of the novel imidazolylsulfonate group is described.
