1120-72-5Relevant articles and documents
Optical Rotatory Dispersion Studies. 134. Absolute Configuration and Circular Dichroism Spectrum of (R)-Cyclopentanone. Demonstration of a Conformational Isotope Effect
Sundararaman, P.,Barth, Guenter,Djerassi, Carl
, p. 5004 - 5007 (1981)
The absolute configuration of (R)-cyclopentanone is established through synthesis using as the key step chiral epoxidation with the Sharpless reagent.Its circular dichroism (CD) spectrum is unusual in that it exhibits a bisignate Cotton effect being negative at 310 and positive at 275 nm.From the interpretation on the variable-temperature CD measurements, the unexpected conclusion is reached that the twist conformation with the deuterium in the quasi-equatorial position is energetically preferred by ca. 10 +/- 2 cal/mol.Evidently, even at room temperature, the contribution toward the spectrum resulting from the conformational isotope effect is of the same or larger amplitude but opposite sign compared to the difference between the partial octant contributions of an α-quasi-equatorial and α-quasi-axial deuterium substituent.
Synthesis of cycloalkanones from dienes and allylamines through C-H and C-C bond activation catalyzed by a rhodium(I) complex
Lee, Dae-Yon,Kim, In-Jung,Jun, Chul-Ho
, p. 3031 - 3033 (2002)
Formaldehyde in disguise: The allylic amine 1 is used as a masked form of formaldehyde in the rhodium-catalyzed cyclization of dienes 2. The reaction provides access to various cycloalkanones 3 through chelation-assisted C-H- and C-C-bond activation.
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Dreiding,Hartman
, p. 1216 (1956)
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Girard,C. et al.
, p. 3329 - 3332 (1974)
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Chemo- and regioselective conversion of epoxides to carbonyl compounds in 5 M lithium perchlorate-diethyl ether medium
Sudha,Malola Narasimhan,Geetha Saraswathy,Sankararaman
, p. 1877 - 1879 (1996)
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Brown,H.C.,Negishi,E.
, p. 5477 - 5478 (1967)
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Huang,S.L. et al.
, p. 297 - 299 (1978)
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The alkylation of silyl enol ethers with SN1-unreactive iodides in the presence of silver trifluoroacetate
Jefford, Charles W.,Sledeski, Adam W.,Lelandais, Patrick,Boukouvalas, John
, p. 1855 - 1858 (1992)
Silyl enol ethers can be effectively alkylated with primary n-alkyl iodides in the presence of silver trifluoro-acetate to give monoalkyl ketones.
Conversion of furfural into cyclopentanone over Ni-Cu bimetallic catalysts
Yang, Yanliang,Du, Zhongtian,Huang, Yizheng,Lu, Fang,Wang, Feng,Gao, Jin,Xu, Jie
, p. 1932 - 1940 (2013)
The conversion of furfural into cyclopentanone over Ni-Cu bimetallic catalysts was studied under hydrogen atmosphere. Furfuryl alcohol, 4-hydroxy-2-cyclopentenone and 2-cyclopentenone were verified as three key intermediates. Rearrangement of the furan ring was independent of hydrogenation, starting from furfuryl alcohol rather than furfural. The opening and closure of the furan ring were closely related to the attack of a H2O molecule on the 5-position of furfuryl alcohol. Prior hydrogenation of the aldehyde group accounted for the different reactivity of furfural and furfuryl alcohol. The high selectivity of cyclopentanone was ascribed to the presence of 2-cyclopentenone.
Synthesis of (1-S) and (1-R) cis 2-methylcyclopentanols through lipase mediated resolution
Reinhold,Rosati
, p. 1187 - 1190 (1994)
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Efficient and selective hydrogenation of biomass-derived furfural to cyclopentanone using Ru catalysts
Fang, Ruiqi,Liu, Hongli,Luque, Rafael,Li, Yingwei
, p. 4183 - 4188 (2015)
The selective hydrogenation of furfural into cyclopentanone is an attractive transformation to advance in the sustainable synthesis of important chemicals from biomass. A supported Ru nanoparticle catalyst on an acidic MOF material (Ru/MIL-101) was designed for the highly active and selective conversion of furfural to cyclopentanone in aqueous media. Complete conversion of furfural with a selectivity higher than 96% was achieved within 2.5 h at 160 °C and 4.0 MPa H2 pressure.
Muchamedova,Kudrjavceva
, (1968)
Overberger et al.
, p. 620 (1963)
METHOD FOR INTRODUCING SUBSTITUENT INTO alpha,beta-UNSATURATED KETONE AND METHOD FOR SYNTHESIZING PROSTAGLANDIN USING THE SAME
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Paragraph 0044-0046, (2021/11/20)
The present invention provides a method for introducing substituents into the α-position and the β-position of an α,β-unsaturated ketone, which not only can be used for the synthesis of a prostaglandin by a three-component coupling process, but also enables synthesis of a prostaglandin in a high yield by one-pot operation without requiring the use of a large excess amount of any of the three components required for the synthesis or using a highly toxic heavy metal as a catalyst or a solvent that is highly toxic to living bodies, and a method for synthesizing a prostaglandin using the same technical means. The method for introducing substituents into an α,β-unsaturated ketone according to the present invention is a method for introducing substituents into the carbon at the α-position and the carbon at the β-position of an α,β-unsaturated ketone, including: a first step of mixing alkyllithium and trialkylalkenyl tin in which tin atom binds to the vinyl position of the alkenyl group; a second step of mixing the mixture of the first step and dialkylzinc; a third step of mixing the mixture of the second step and an α,β-unsaturated ketone; and a fourth step of mixing the mixture of the third step and a trifluoromethanesulfonate compound.
A robust and stereocomplementary panel of ene-reductase variants for gram-scale asymmetric hydrogenation
Nett, Nathalie,Duewel, Sabine,Schmermund, Luca,Benary, Gerrit E.,Ranaghan, Kara,Mulholland, Adrian,Opperman, Diederik J.,Hoebenreich, Sabrina
, (2021/01/25)
We report an engineered panel of ene-reductases (ERs) from Thermus scotoductus SA-01 (TsER) that combines control over facial selectivity in the reduction of electron deficient C[dbnd]C double bonds with thermostability (up to 70 °C), organic solvent tolerance (up to 40 % v/v) and a broad substrate scope (23 compounds, three new to literature). Substrate acceptance and facial selectivity of 3-methylcyclohexenone was rationalized by crystallisation of TsER C25D/I67T and in silico docking. The TsER variant panel shows excellent enantiomeric excess (ee) and yields during bi-phasic preparative scale synthesis, with isolated yield of up to 93 % for 2R,5S-dihydrocarvone (3.6 g). Turnover frequencies (TOF) of approximately 40 000 h?1 were achieved, which are comparable to rates in hetero- and homogeneous metal catalysed hydrogenations. Preliminary batch reactions also demonstrated the reusability of the reaction system by consecutively removing the organic phase (n-pentane) for product removal and replacing with fresh substrate. Four consecutive batches yielded ca. 27 g L?1 R-levodione from a 45 mL aqueous reaction, containing less than 17 mg (10 μM) enzyme and the reaction only stopping because of acidification. The TsER variant panel provides a robust, highly active and stereocomplementary base for further exploitation as a tool in preparative organic synthesis.
Selective C-C Bond Cleavage of Cycloalkanones by NaNO2/HCl
He, Tianyu,Chen, Dengfeng,Qian, Shencheng,Zheng, Yu,Huang, Shenlin
supporting information, p. 6525 - 6529 (2021/09/02)
A novel selective fragmentation of cycloalkanones by NaNO2/HCl has been established. The C-C bond cleavage reaction proceeds smoothly under mild conditions, selectively affording versatile keto acids or oxime acids. The methodology can streamline the synthesis of valuable chiral molecules and isocoumarins from readily available feedstocks.