Ring opening base-catalysed nucleophilic

On the other hand, reaction of the sulfonyl chloride 397 with excess morpholine, pyrrolidine and piperidine (three equivalents) afforded a mixture of the sulfonamides 400 and 401. The succinimidosulfonamide 401 was formed by simultaneous nucleophilic substitution at sulfur and Michael addition of the amine to the activated alkenic double bond. The pure maleimidosulfonamide 400 could be prepared by column chromatography of the mixture. The reaction of N- p-chlorosulfonylphenyl) maleimide 397 with excess dimethylamine or diethylamine in methanol as solvent resulted in the formation of ring-opened products. For instance, in the reaction with diethylamine, the methyl ester 402 was formed by base-catalysed nucleophilic ring-opening by the solvent (methanol) this ring... 

A review of the metal-catalysed ring opening of achiral epoxides by achiral carbon-, sulfur-, nitrogen- and halogen-containing nucleophiles and kinetic resolution of racemic epoxides has been published.24 The review also discusses the reactions of chiral bases with epoxides that give allylic alcohols. 

Acid-catalysed ring-opening of 20a,21-epoxypregnanes (72) gave both the 20o,21- (73) artd 20, 21-diols (74), by non-selective attack of water. Base-catalysed hydrolysis, in contrast, gave only the 20a,21-diol, by nucleophilic attack of OH at C-21. The 20o,21-diol also resulted from epoxide opening by either dimethyl... 

The ring opening reactions of pyrylium salts has been extended to include aldehydes as carbon nucleophiles the product of this base-catalysed sequence is a... 

Nucleophilic bimolecular ring-opening of ethylene oxide by the hydride anion has been investigated theoretically. Molecular orbital calculations of the interaction energy (a combination of coulomb, exchange, delocalization, and polarization interaction terms) were carried out. The kinetics and stereochemistry of base-catalysed polymerization of epoxides have been studied using optically active epoxide monomers. 

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