2780-89-4Relevant articles and documents
Process for the preparation of ε-caprolactam
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Page column 11,12, (2008/06/13)
Process for the preparation of ε-caprolactam, in which in a step (a) a compound with the general formula: O=CH—(CH2)4—C(O)—R??(1) in which R is —OH, —NH2or O—R′, in which R′ is an organic group with 1 to 10 carbon atoms, is contacted with ammonia and hydrogen in a suitable solvent at elevated pressure in the presence of a hydrogenation catalyst to a mixture of primary amino compounds and ε-caprolactam, followed by a separate second step (b) in which the primary amino compounds are reacted to ε-caprolactam, wherein the solvent in step (a) is an aqueous medium, including water, the yield to ε-caprolactam in step (a) is more than 10%, calculated on the initial molar amount of the compound according to formula (1), that ε-caprolactam is separated from the aqueous mixture obtained in step (a) by extraction and that the aqueous mixture resulting from the extraction, containing the primary amino compounds, is used in step (b).
HYDROLYSIS OF ESTERS OF N-RETINYLIDENEAMINO ACIDS
Karpenko, E. P.,Mitsner, B. I.,Zvonkova, E. N.,Evstigneeva, R. P.
, p. 1669 - 1673 (2007/10/02)
The hydrolysis rate of the ester bond in the molecules of methyl esters of the N-retinylidene derivatives of aliphatic amino acids depends on their chain lengths.The higher reaction rates for the derivatives of γ-aminobutyric and δ-aminovaleric acids are explained by intramolecular catalysis.