Collect. Czech. Chem. Commun.
1990, 55, 202-222
https://doi.org/10.1135/cccc19900202
Kinetics and mechanism of solvolysis of N-aryl sulfuric diamides
Jaromír Kaváleka, Ulrika Králíkováb, Vladimír Macháčeka, Miloš Sedláka and Vojeslav Štěrbaa
a Department of Organic Chemistry, Institute of Chemical Technology, 532 10 Pardubice
b Department of Organic Chemistry, Slovak Technical University, 812 37 Bratislava
Abstract
The methanolysis and hydrolysis kinetics have been studied with the following sulfuric diamide derivatives: N-methyl-N-phenyl- (IIIa), N-methyl-N-(4-methoxycarbonylphenyl)- (IIIb), N-(4-methoxycarbonylphenyl)- (IIIc), N-methyl-N-(2-methoxycarbonylphenyl)- (IIId), N-(2-methoxycarbonylphenyl)- (IIIe), and N-methyl-N-(2,4-dibromophenyl)- (IIIf). The solvolyses of the neutral substrates IIIa and IIIb proceed by the addition-elimination mechanism. In the presence of the solvent lyate ions the solvolyses go by the E1cb mechanism. The solvolyses of the conjugated bases of compounds IIIa and IIIb are subject to general acid catalysis, the effects of the ring substituents being opposite to those in the addition-elimination mechanism. The solvolyses of compounds IIId and IIIf exhibit a distinct catalytic effect of neighbouring group; the reaction goes via a reactive intermediate, the transformation of the intermediate into the solvolysis product being subject to general acid and base catalysis.
