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Showing papers in "Journal of Organic Chemistry in 1974"








Journal ArticleDOI
TL;DR: In this article, the use of C nmr spectra for the determination of configurations of oximes is described, and the problems of quantitative analysis of syn-anti mixtures of oxime by cmr, because of differential T_1 and Overhauser effects, are considered.
Abstract: The use of ^(13)C nmr (cmr) spectra for the determination of configurations of oximes is described. The problems of quantitative analysis of syn-anti mixtures of oximes by cmr, because of differential T_1 and Overhauser effects, are considered. Chemical shifts for the cmr resonances of a number of aldehydes and ketones are reported.

210 citations


Journal ArticleDOI
TL;DR: The effects of substitution, lanthanide-shift reagents, solvent changes, and tautomerism were investigated in this article, where it was concluded that chemical shifts are of limited value to ascertain the positions of tautomers.
Abstract: The effects of substitution, lanthanide-shift reagents, solvent changes, and tautomerism were investigated on the ^(13)C chemical shifts of pyrrole, pyrazole, imidazole, s- and v-triazole, and tetrazole. It was concluded that ^(13)C chemical shifts are of limited value to ascertain the positions of tautomeric equilibrium for rapidly interconverting azole tautomers.

174 citations




Journal ArticleDOI
TL;DR: In this article, a Losung von wasserfreiem Fe(III)-chlorid in Acetanhydrid werden Ather (I) uber die Zwischenstufen (III) zu den Acetaten (IV) bzw.
Abstract: Durch eine Losung von wasserfreiem Fe(III)-chlorid in Acetanhydrid werden Ather (I) uber die Zwischenstufen (III) zu den Acetaten (IV) bzw. (V) gespalten.


Journal ArticleDOI
TL;DR: Pyrolysis of several structurally different amino acids in a column at 500 C showed differences in the mechanisms and final products, and alpha amino acids with alpha alkyl substituents appear to stabilize the developing negative charge formed by partial heterolytic cleavage of the alpha carbon - NH3 bond.
Abstract: Pyrolysis of several structurally different amino acids in a column at 500 C showed differences in the mechanisms and final products. The aliphatic protein amino acids decompose mainly by simple decarboxylation and condensation reactions, while the beta amino acids undergo deamination to unsaturated acids. Alpha amino acids with alpha alkyl substituents undergo an unusual intramolecular SN1 reaction with the formation of an intermediate alpha lactone which decomposes to yield a ketone. The alpha alkyl substituents appear to stabilize the developing negative charge formed by partial heterolytic cleavage of the alpha carbon - NH3 bond. The gamma and delta amino acids give 2-pyrrolidinone and 2-piperidone respectively, while the epsilon acids yield mixed products.