Ring‐chain tautomeric equilibria in the 1,3,4,6‐tetraketone series 1 have been examined and the identification of the chain‐form 2 and hydroxyfuranone 3 has been accomplished from 1H‐nmr spectra; the relative contribution of the two depends on the structure and also on the solvent. Conversions of 1 into 3(2H)furanones 4 and 5 involving the cyclic tautomer 3 are described.

Derivatives of aminomethylglyoxal, the simplest of the series of aminoalkylglyoxals, have recently been prepared using glycine as starting material (1).We have now prepared, following the same method and starting with L-alanine, @-alanine, and L-tyrosine, the derivatives of the corresponding aminoalkylglyoxals (VIa-e).From the above mentioned amino acids, the N-phthaloylacyl chlorides (Ia-c), the diazoketones (Ha-c), and the bromoketones (IIIa-c) were prepared, from which, following the method of Krohnke and Bomer (2), the glyoxals (VIa-e) were obtained through the reaction stages IV-VI in the form of their N-phthaloyl derivatives.The bisethylenemercaptals and quinoxaline derivatives of these glyoxals were also prepared.a-Phthalimidoethylglyoxal (VIa) derived from L-alanine, and a-(phthalimid0)-@-(p-methoxypheny1)ethylglyoxal (VIc) derived from 0-methyl-L-tyrosine are optically active, showing [a], +8.7" and [a], -1.4" respectively.The N-phthaloylglyoxals (VIa-c) were obtained after filtration through a column of Alto3 and high vacuum distillation as yellow oils; the glyoxals of L-alanine and @-alanine ultimately crystallized.Aclcnmledgment, We are indebted to the Rockefeller Foundation for financial assistance. (IIIa). To a suspension of (-)-l-diazo-3phthalimidobutan-2-one (IIa, 5 9.) prepared following BalenoviO, Cerar, and Fuks (3) in glacial acetic acid (27.5 ml.), 48% hydrobromic acid (5.3 ml.) was added with stirring. After standing for an hour a t room temperature the reaction was complete. The mixture vim then diluted with 300 ml. of water and the crystals were collected. Yield, 6 g. (98.5%) of (-) -1-bro1no-3-phtha1imidobutan-2-one; recrystallization from ether-petroleum ether gave the pure compound, m.p. 66", [a]; -34.7' i 1" (c, 0.14 in acetone). EXPERIMENTAL All melting points are uncorrected. (-)-I -Bromo-3-phlhalimidobutan-2-one

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Notes 5131948. Correlation of the ConJigurations of a-Methyl-p-alanine and Methylsuccinic AcidBy K. BALENOVIC and N. BREGANT CORRELATION of the configurations of (-)-a-methyl-P-alanine (I) and (-)-2-methylbutanol by way of (+)-2-methyl-l-phthalimidobutane, described previously,l indicated the (R)-configuration for this amino-acid.showed that the optical purity of the 2-methyl-l-phthalimidobutane obtained by Raney nickel desulphurisation of (+)-2-methyl-l-phthalimidobutan-3-one ethylene mercaptol depended strongly on the nature of the catalyst, and another method for establishing the configuration of (I) was therefore desirable.CHZNH, rR However, our later experiments

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