3391-90-0Relevant academic research and scientific papers
Regioselective silver-mediated Kondakov-Darzens olefin acylation
Barczak, Nicholas T.,Jarvo, Elizabeth R.
supporting information; experimental part, p. 12912 - 12916 (2011/12/04)
Enone construction: A silver-mediated olefin acylation reaction is described, in which five-, six-, and -seven-membered rings, tetrasubstituted olefins, bridged bicycles, spirocycles, and benzoxepinones are prepared. Highly selective intermolecular reactions are coupled to a Nazarov cyclization for the effective preparation of cyclopentenones, including the core of modhephene (see scheme). Copyright
Flavor and fragrance compositions
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Page/Page column 5, (2008/06/13)
The present invention provides a flavor and fragrance composition which comprises, as the active ingredient, an optically active (1S)-8-mercaptomenthone having an S-form/R-form mixing ratio for the configuration at the 4-position in the range of from 65:35 to 95:5 by weight, wherein the flavor and fragrance composition is for use in food and beverage, fragrances and cosmetics, pharmaceuticals or oral compositions and the like; a product which is scented with the flavor and fragrance composition; and a method for enhancing or modulating odor of the flavor and fragrance composition by adding the optically active (1S)-8-mercaptomenthone.
Lipase-catalyzed resolution of p-menthan-3-ols monoterpenes: Preparation of the enantiomer-enriched forms of menthol, isopulegol, trans- and cis-piperitol, and cis-isopiperitenol
Serra, Stefano,Brenna, Elisabetta,Fuganti, Claudio,Maggioni, Francesco
, p. 3313 - 3319 (2007/10/03)
A study on the enzymic resolution of the most common p-menthan-3-ol monoterpene isomers is described. Enantioenriched alcohols 1, 5, 10, 11 and 12 are obtained by means of the lipase-mediated kinetic acetylation of the corresponding racemic materials. The stereochemical aspects of the enzymic process have been investigated. We found that the structural features of the starting p-menthan-3-ol as well as the kind of lipase used, impacted strongly on the enantioselectivity of the resolution. The potentialities of this approach for preparative purposes are discussed.
An efficient procedure for the preparation of (E)-α-alkylidenecycloalkanones mediated by a CeCl3·7H2O-NaI system. Novel methodology for the synthesis of (S)-(-)-pulegone
Bartoli, Giuseppe,Bosco, Marcella,Dalpozzo, Renato,Giuliani, Arianna,Marcantoni, Enrico,Mecozzi, Tiziana,Sambri, Letizia,Torregiani, Elisabetta
, p. 9111 - 9114 (2007/10/03)
2-Alkylidenecycloalkanones are powerful synthons used as the key intermediates in many important syntheses. Because of their potential, a general method of preparation from readily available starting materials, under very mild conditions, was considered to be worthwhile. Cerium(III) chloride heptahydrate in combination with sodium iodide in refluxing acetonitrile promotes a regio- and stereoselective β-elimination reaction to (E)-2-alkylidenecycloalkanones in 2-(1-hydroxyalkyl)cycloalkanones. The synthetic value of the present procedure is demonstrated by the synthesis of monoterpene (S)-(-)-pulegone (8) in its optically active form.
A versatile cobalt(II)-Schiff base catalyzed oxidation of organic substrates with dioxygen: Scope and mechanism
Punniyamurthy,Bhatia, Beena,Reddy, M. Madhava,Maikap, Golak C.,Iqbal, Javed
, p. 7649 - 7670 (2007/10/03)
Cobalt(II) complex 1a-f derived from Schiff bases act as efficient catalysts during the oxidation of wide range of organic substrates(e.g. alkenes, alcohols, benzylic compounds and aliphatic hydrocarbons) with dioxygen in the presence of aliphatic aldehydes or ketones or ketoesters. EPR studies on 1a-f complexes suggest that the aliphatic carbonyl compounds promote the formation of a cobalt(II)-superoxo species responsible for the oxidation of organic compounds. These studies also demonstrate the role of ligands on cobalt in controlling the chemoselectivity of these oxidations. A plausible mechanistic rational is also provided for these oxidations.
Regio- and enantio-selective enolisations of cyclic ketones using chiral lithium amide bases
Bambridge, Kimberley,Clark, Barry P.,Simpkins, Nigel S.
, p. 2535 - 2542 (2007/10/02)
Enolisations of 3-methylcyclohexanone 16, and of a trans-fused perhydroisoquinolone derivative 8, using several chiral lithium amide bases have been examined.In reactions involving a single enantiomer of the ketone 8, the use of a chiral base can result in enhancement or reversal of the normal regioselectivity of enolisation to give the enol silane derivatives 9 and 10, depending on the configuration of the base used.Similar matched and mismatched results are observed when (R)-3-methylcyclohexanone, (R)-16, is treated with either enantiomer of the chiral base 3.A new type of kinetic resolution, termed regiodivergent resolution, is observed when enolisation of the racemic ketones 8 or 16 is carried out using the chiral base 3.
Cobalt catalyzed oxidation of secondary alcohols with dioxygen in the presence of 2-methylpropanal
Kalra, Swinder Jeet Singh,Punniyamurthy,Iqbal, Javed
, p. 4847 - 4850 (2007/10/02)
Cobalt schiff base complex 2 catalyses the oxidation of a wide range of secondary alcohols to the corresponding ketones in the presence of dioxygen and 2-methylpropanal.
Cobalt(II) Schiffs base complex catalysed oxidation of alcohols with dioxygen in the presence of ethyl 2-oxocyclopentanecarboxylate
Punniyamurthy,Iqbal, Javed
, p. 4007 - 4010 (2007/10/02)
Cobalt(II) Schiffs base complex 1 catalyses the oxidation of primary and secondary alcohols to aldehydes and ketones respectively, in the presence of dioxygen and ethyl 2-oxocyclopentanecarboxylate 2 at 60-70° C.
Tetramethyl-1-oxaspiro[2.5]octane
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, (2008/06/13)
New 4,4,5,8-tetramethyl-1-oxaspiro[2.5]octane. A process for its preparation starting from 2,2,3,6-tetramethyl-1-cyclohexanone is described. 4,4,5,8-Tetramethyl-1-oxaspiro[2.5]octane is a useful raw material for the preparation of 2,2,3,6-tetramethyl-cyclohexane-carbaldehyde, a key intermediate for the synthetis of valuable fragrance ingredients.
Potassium Chlorochromate on a Solid Support: A Convenient and Mild Reagent for the Oxidation of Alcohols
Carlsen, Per H. J.,Husbyn, Mette,Braenden, Jon E,,Eliason, Robert
, p. 485 - 488 (2007/10/02)
The oxidation of primary and secondary alcohols by potassium chlorochromate supported on alumina or silica gel is reported.The results indicate that the yields in some cases depend on the support medium.Benzylic and secondary alcohols are oxidized in the best yields.The effect of solvent on the reaction is discussed and the conclusion is drawn that the best yields are obtained in non-polar solvents.
