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Lithiation of 1-naphthonitrile provides the 2-lithio derivative exclusively. Reaction of this intermediate with ten different electrophiles produces 2-substituted derivatives in moderate to good yields. 2-Alkyl-1-naphthonitriles are readily lithiated and further alkylated to provide alkyl substituents modified at the α position. The pKavalues for the hydrogen at the 2-position of 1-cyanonaphthalene and 2-methyl-1-cyanonaphthalene have been determined to be 36.3 and 28.5, respectively.

15N nuclear magnetic resonance chemical shifts and one-bond 15N—31P couplings are reported for a series of five N-arylphosphoramidates and four N-arylphosphorimidates. Results are interpreted in terms of an extensively delocalized N lone pair in the phosphoramidates, with pπ–pπdonation into the aromatic ring being dominant over pπ–dπdonation from nitrogen to phosphorus.

The experimental evidence indicates that the Karplus curve, which relates the coupling constant between hydrogens on vicinal carbons and the dihedral angle defined by the hydrogens, is subject to displacement. An upward displacement of 2.2 c.p.s. is required to account for the coupling constants found for the neighboring hydrogens in both 1,3-dioxolane and its 2,2-dimethyl derivative. On this basis, the compounds exist in conformations wherein the cis neighboring hydrogens define dihedral angles of 35° and 41°, respectively.

The 60 Mc/s proton spectra of methyl 2-bromo-3-fluoropropanoate and the 3-bromo-2-fluoro isomer have been analyzed completely with the aid of heteronuclear spin decoupling to illustrate an extension of the double resonance technique to ABCX spin systems. These results provide confirmatory evidence of the magnitude and relative signs of geminal and vicinal proton–proton and proton–fluorine coupling constants.

The effect of solvent on the stereochemical course of deuteration of benzyl methyl sulfoxide has been studied by two methods. In the first, the relative rates of exchange of the diastereotopic methylene protons were found to vary from 14:1 (D2O/NaOD) to 0.5:1 (t-butanol-OD/NaO-t-butyl). Experiments on quenching α-lithiobenzyl methyl sulfoxide with D2O gave the same diastereomers in ratios ranging from 1.7:1 (DMSO) to 0.065:1 (THF). The significance of these findings in relation to previous work on conformational stabilities of α-sulfinyl carbanions is discussed.

The kinetics of the acid‐catalyzed isotope 18O exchange in the nucleophilic addition of H218O to the ketones (I) and (II) show an antiperiplanar effect for the C‐C bond, which is at least 1.9 kcal/mol greater than for the n‐σ* interaction with the C‐H bond.

The ketones (I) are treated with trimethylchlorosilane in the presence of dimethyl sulfoxide and catalytic amounts of tetrabutylammonium bromide, producing the α‐chloro ketones (II).

ACETOACETIC acid is an important and widespread intermediary metabolite, being formed in the oxida-tive degradation of fatty acids and of certain amino-acids. For comparison with acetoacetic acid, we have prepared1the compound ethyl ω-fluoroacetoacetate, FCH2COCH2COOC2H5. From a consideration of its structural similarity to 4-fluorobutyric acid2and of its probable interference with the mechanism of fatty acid metabolism, we predicted that it would produce toxic symptoms.