35394-09-3Relevant articles and documents
Asymmetric synthesis of O-protected acyloins using enoate reductases: Stereochemical control through protecting group modification
Winkler, Christoph K.,Stueckler, Clemens,Mueller, Nicole J.,Pressnitz, Desiree,Faber, Kurt
supporting information; experimental part, p. 6354 - 6358 (2011/02/24)
O-Protected cyclic acyloins were obtained in nonracemic form through asymmetric bioreduction of α,β-unsaturated alkoxy ketones by using 11 different enoate reductases from the "Old Yellow Enzyme" family. The stereochemical outcome of the biotransformation could be switched by variation of the O-protecting group or by the ring size of the substrate, which allows access to both stereoisomers in up to >97 % ee Whereas α-alkoxy enones were readily accepted as substrates, β-analogs were not converted. Overall, α-alkoxy enones represent a novel type of substrate for flavin-dependent ene-reductases. Copyright
Indirect electrochemical oxidation of cyclic ketones: Influence of ring size, mediator and supporting electrolyte on the result of the reaction
Barba, Fructuoso,Elinson, Michail N.,Escudero, Jose,Feducovich, Sergey K.
, p. 4427 - 4436 (2007/10/03)
The result of the indirect electrochemical oxidation of cyclic ketones in methanol in an undivided cell in the presence of sodium halides depends on the ring size of ketone and the type of mediator. Selectivity of the reaction in some cases and current efficiency are increased by addition of supporting electrolyte - sodium hydroxide. Formation of cyclic 2,2-dimethoxycycloalkanols and the electrochemically induced Favorskii rearrangement with the formation of methyl cycloalkencarboxylates containing in the ring one carbon atom less than starting ketone are the main ways of the indirect electrochemical oxidation of cyclic ketones.
Aldol additions of pinacolone lithium enolate with ketones: Reactivities governed predominantly by field effects
Das, Goutam,Thornton, Edward R.
, p. 1302 - 1312 (2007/10/02)
The relative reactivities of representative α- and β-heterosubstituted acyclic, cyclic (five- and six-membered), and aromatic ketones with the lithium enolate of pinacolone in diethyl ether at -78 °C were determined. The order of reactivities of monosubst
Generation and Cycloaddition of Cyclopentenylium-2-olate from 2-Chlorocyclopentanone under Alcoholysis Conditions
Froehlisch, Baldur,Joachimi, Roland
, p. 1951 - 1960 (2007/10/02)
2-Chlorocyclopentanone (1a) is solvolysed in basic methanol or 2,2,2-trifluoroethanol to form 2-methoxy- or 2-(2,2,2-trifluoroethoxy)cyclopentanone, respectively (1c,1d).No Favorskii rearrangement is observed.An enolization-ionization mechanism via the oxallyl intermediate 3 is proposed.In competition with the attack by trifluoroethanol the reactive intermediate undergoes cycloadditions with 1,3-butadiene and isoprene to form the bicyclononenones 6a, b.Cyclopentadiene, spiro-hepta-4,6-diene, 6,6-dimethylfulvene, furan, 2-methylfuran, and 2,5-dimethylfuran give the tricycles 7a-f, where the anti stereoisomer (7α) predominates.Products with only one carbon-carbon bound formed (8-11) were observed with isoprene, spiro-hepta-4,6-diene, spironona-1,3-diene, and 2-methylfuran, indicating a two step mechanism of the oxallyl attack by way of the zitterionic intermediates 16a- d.
ERZEUGUNG UND CYCLOADDITION VON ALLYLIUMIONEN AUS α-HALOGENKETONEN UNTER SOLVOLYSE-BEDINGUNGEN
Foehlisch, Baldur,Gottstein, Wolfgang,Kaiser, Roland,Wanner, Iris
, p. 3005 - 3009 (2007/10/02)
Some α-haloketones react with furan in methanolic solution in the presence of base to form the 3-oxo-8-oxabicyclooct-6-enes (11), the products derived from a cycloaddition of an allylium intermediate (5 or 6).
