Synthesis of Glycosyl Cyanides by the Reaction of 1-5-Phosphorothioates of Carbohydrates with Trimethylsilyl Cyanide
نویسنده
چکیده
A new procedure is described for the synthesis of a,/?-glycosyl cyanides by the reaction of per-O-benzylated S-a-D-glycopyranosyl phosphorothioates with trimethylsilyl cyanide in the presence of Lewis acid. Starting S-glycosyl phosphorothioates are prepared, directly, from O-benzyl protected reducing D-hexopyranoses (gluco-, galacto-, manno-) and alkylammonium salt of phosphorothioic acid under Lewis acid catalysis.
منابع مشابه
Unexpected formation of complex bridged tetrazoles via intramolecular 1,3-dipolar cycloaddition of 1,2-O-cyanoalkylidene derivatives of 3-azido-3-deoxy-D-allose.
An unexpected and interesting intramolecular side reaction occurred during the attempted synthesis of glycosyl cyanides upon treatment of 1-O-acetyl-3-azido-3-deoxyallose derivatives with TMSCN and different Lewis acids. Exo-1,2-O-cyanoalkylidene derivatives formed by neighboring group participation and attack of cyanide underwent, after Lewis-acid mediated isomerization to the endo-isomer, int...
متن کاملPhosphotungstic Acidcatalyzed Strecker Three-Component Reaction of Amino Acids, Aldehydes, and Trimethylsilyl Cyanide
A simple and efficient one-pot, three-component Strecker reaction of protected amino acids, aromatic aldehydes, and trimethylsilyl cyanide has been developed for the synthesis of chiral α-amino nitriles. The reaction was carried out in the presence of catalytic amount of phosphotungstic acid (H3[P(W3O10)4]) as an environmentally friendly cata...
متن کاملp-Toluenesulfonic acid catalyzed rapid and efficient protocol for one-pot synthesis of α-amino nitriles
A simple, rapid and efficient practical method for one-pot synthesis of α-amino nitriles has been achieved by a threecomponent condensation of carbonyl compounds, amines and trimethylsilyl cyanide in the presence of p-toluenesulfonic acid (p-TsOH) as a catalyst at ambient temperature. Operational simplicity, economic consideration, high yield, short reaction time and low toxicity are the key fe...
متن کاملKinetics and mechanism of the racemic addition of trimethylsilyl cyanide to aldehydes catalysed by Lewis bases.
The mechanism by which four Lewis bases, triethylamine, tetrabutylammonium thiocyanate, tetrabutylammonium azide and tetrabutylammonium cyanide, catalyse the addition of trimethylsilyl cyanide to aldehydes is studied by a combination of kinetic and spectroscopic methods. The reactions can exhibit first or second order kinetics corresponding to three different reaction mechanisms. Spectroscopic ...
متن کاملUltrasound-promoted Catalyst-free Synthesis of α-Aminonitriles in 1-Butyl-3-methylimidazolium Bromide ([Bmim]Br) as a Reusable Neutral Ionic Liquid
A catalyst-free one-pot three component methodology for the synthesis of α-aminonitriles under ultrasonic irradiation at room temperature using [Bmim]Br as a neutral reaction medium is described. A broad range of substrates including the aromatic, heteroaromatic and aliphatic aldehydes were condensed with amines (aliphatic and aromatic) and trimethylsilyl cyanide (TMSCN). Using this method, all...
متن کامل