Ruhemann, Siegfried et al. published their research in Journal of the Chemical Society, Transactions in 1912 | CAS: 39163-39-8

Ethyl 2-oxo-2-(2-oxocyclopentyl)acetate (cas: 39163-39-8) belongs to esters. Esters perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Polyesters are important plastics, with monomers linked by ester moieties. Many esters have the potential for conformational isomerism, but they tend to adopt an s-cis (or Z) conformation rather than the s-trans (or E) alternative, due to a combination of hyperconjugation and dipole minimization effects. The preference for the Z conformation is influenced by the nature of the substituents and solvent, if present. Lactones with small rings are restricted to the s-trans (i.e. E) conformation due to their cyclic structure.Product Details of 39163-39-8

Studies on Cyclic Ketones. I was written by Ruhemann, Siegfried. And the article was included in Journal of the Chemical Society, Transactions in 1912.Product Details of 39163-39-8 This article mentions the following:

(CO2Et)2, NaOEt, and cyclopentanone, in Et2O, gave ethyl cyclopentanone-2,5-dioxalate (I), deep yellow plates, m. 114-5°, and ethyl cyclopentanone-2-oxalate, yellow, b15 152-3°; needles, m. 26-7°. Both esters give deep red colors with FeCl3. (I) gives a salt containing 2 mols. PhNHNH2; colorless crystals. Cyclopentanone 2,5-dioxalic acid, yellow needles, m. 210° (decompose). (CO2Et)2, NaOEt, and 1-methyl-cyclopentane-3-one form only ethyl 1-methylcyclopentane-3-one-4-oxalate, pale yellow oil, b14 150°. Ethyl 1,3-dimethyl-Δ3-cyclohexene-5-one-6-oxalate (II), yellow needles, m. 132-3°. Acid, yellow prisms, m. 178° (decompose). Ethyl 1-hydrindone-2-oxalate (III), colorless needles, m. 74-5°. Salt with 1 PhNHNH2, colorless crystals; unstable. Acid, faintly yellow needles, m. 214° (decompose). 5,6-Methylenedioxy-1-hydrindone-β-oxalic acid, using C6H6 as solvent and hydrolyzing the ester, which could not be purified, yellow needles, m. 260° (decompose). (III), heated in EtOH with PhNHNH2.HCl and a little HCl, gave ethyl 1-phenyl-4,5-indenopyrazole-3-carboxylate (IV), pale yellow needles, m. 117-8°. Acid, needles, m. 250-1° (decompose); also prepared direct from the acid of (III). Silver salt, curdy, not attacked by light. Ethyl 4,5-indenopyrazole-3-carboxylate, colorless prisms, m. 174°. Acid, very slightly soluble, m. 310° (decompose). α-Hydrindone, NaOEt, and PhC îŒ?CCO2Et yielded 6-phenyl-2,3-indeno-4-pyrone (V), needles, with 1 H2O, m. 169° (for this reaction cf. C. A., 2, 1830, 3062). Chloroplatinate, plates. p-ONC6H4NMe2 acts on 1,3-dimethyl-Δ3-cyclohexene-5-one and succinylosuccinic ester as an oxidizing agent, instead of condensing with these. An additional double bond is introduced into the cyclic ketone and the base is reduced to Me2NC6H4N2OC6H4NMe2. In the experiment, the researchers used many compounds, for example, Ethyl 2-oxo-2-(2-oxocyclopentyl)acetate (cas: 39163-39-8Product Details of 39163-39-8).

Ethyl 2-oxo-2-(2-oxocyclopentyl)acetate (cas: 39163-39-8) belongs to esters. Esters perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Polyesters are important plastics, with monomers linked by ester moieties. Many esters have the potential for conformational isomerism, but they tend to adopt an s-cis (or Z) conformation rather than the s-trans (or E) alternative, due to a combination of hyperconjugation and dipole minimization effects. The preference for the Z conformation is influenced by the nature of the substituents and solvent, if present. Lactones with small rings are restricted to the s-trans (i.e. E) conformation due to their cyclic structure.Product Details of 39163-39-8

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics