25312-34-9Relevant academic research and scientific papers
The new halolactones and hydroxylactone with trimethylcyclohexene ring obtained through combined chemical and microbial processes
Grabarczyk, Malgorzata,Maczka, Wanda,Winska, Katarzyna,Zarowska, Barbara,Aniol, Miroslaw
, p. 195 - 203 (2014)
The commercially available racemic (±) α-ionone was used as a substrate for the four-step chemical synthesis of three new γ- halolactones. During these processes known α-ionol and new compounds: γ,δ-unsaturated ester ((6E)-5-(2,6,6-trimethylcyclohex-2-en-1-yl) oct-6-en-3-one) (3) and γ,δ-unsaturated acid ((6E)-3-(2,6,6- trimethylcyclohex-2-en-1-yl)hex-4-enoic acid) (4), were obtained as intermediates. γ,δ-Unsaturated acid was used as a substrate for obtaining also new compounds: 5-(1-chloroethyl)-4-(2,6,6-trimethylcyclohex-2-en- 1-yl)dihydrofuran-2(3H)-one (5), 5-(1-bromo)-4-(2,6,6-trimethylcyclohex-2-en-1- yl)dihydrofuran-2(3H)-one (6) and 5-(1-iodo)-4-(2,6,6-trimethylcyclohex-2-en-1- yl)dihydrofuran-2(3H)-one (7). At the last step these halolactones were converted into the hydroxylactone by microorganisms. Several fungal strains (Fusarium species, Syncephalastrum racemosum, Botrytis cinerea) were tested. Most of the selected microorganisms transformed these lactones by hydrolytic dehalogenation into a new 5-(1-hydroxyethyl)-4-(2,6,6-trimethylcyclohex-2-en-1- yl)dihydrofuran-2(3H)-one (8), mainly the (+) stereoisomer. The hydroxylactone obtained during biotransformation has been examined for its antimicrobial activity against bacteria, yeasts and fungi. It was found that this compound exhibits growth inhibition against some tested microorganisms. The structure of all the substrates and products was established on the basis of their spectral data.
Capturing the Monomeric (L)CuH in NHC-Capped Cyclodextrin: Cavity-Controlled Chemoselective Hydrosilylation of α,β-Unsaturated Ketones
Bistri-Aslanoff, Olivia,Derat, Etienne,Leloux, Sébastien,Leyssens, Tom,Ménand, Micka?l,Meijide Suárez, Jorge,Riant, Olivier,Roland, Sylvain,Sollogoub, Matthieu,Xu, Guangcan,Zhang, Pinglu,Zhang, Yongmin
supporting information, p. 7591 - 7597 (2020/03/23)
The encapsulation of copper inside a cyclodextrin capped with an N-heterocyclic carbene (ICyD) allowed both to catch the elusive monomeric (L)CuH and a cavity-controlled chemoselective copper-catalyzed hydrosilylation of α,β-unsaturated ketones. Remarkably, (α-ICyD)CuCl promoted the 1,2-addition exclusively, while (β-ICyD)CuCl produced the fully reduced product. The chemoselectivity is controlled by the size of the cavity and weak interactions between the substrate and internal C?H bonds of the cyclodextrin.
Fungi-mediated biotransformation of the isomeric forms of the apocarotenoids ionone, damascone and theaspirane
Serra, Stefano,De Simeis, Davide
, (2019/01/16)
In this work, we describe a study on the biotransformation of seven natural occurring apocarotenoids by means of eleven selected fungal species. The substrates, namely ionone (α-, β- and γ-isomers), 3,4-dehydroionone, damascone (α- and β-isomers) and theaspirane are relevant flavour and fragrances components. We found that most of the investigated biotransformation reactions afforded oxidized products such as hydroxy- keto- or epoxy-derivatives. On the contrary, the reduction of the keto groups or the reduction of the double bond functional groups were observed only for few substrates, where the reduced products are however formed in minor amount. When starting apocarotenoids are isomers of the same chemical compound (e.g., ionone isomers) their biotransformation can give products very different from each other, depending both on the starting substrate and on the fungal species used. Since the majority of the starting apocarotenoids are often available in natural form and the described products are natural compounds, identified in flavours or fragrances, our biotransformation procedures can be regarded as prospective processes for the preparation of high value olfactory active compounds.
Eco-friendly stereoselective reduction of α,β-unsaturated carbonyl compounds by Er(OTf)3/NaBH4 in 2-MeTHF
Nardi, Monica,Sindona, Giovanni,Costanzo, Paola,Oliverio, Manuela,Procopio, Antonio
, p. 1132 - 1135 (2015/02/19)
An operationally simple and environmentally benign catalytic procedure has been developed to selectively reduce different α,β-unsaturated ketones. The corresponding allylic alcohols are obtained with high chemo- and diastereoselectivity using Er(OTf)3 and NaBH4 in 2-MeTHF. This protocol reduces the amount of catalyst and NaBH4 needed, compared to classical procedures and the stages of extraction/purification are carried out in aqueous solutions avoiding the use of toxic solvents. Taking into account that Er(OTf)3 can be considered even less toxic than table salt and the 'greenness' of 2-MeTHF as a solvent, the system Er(OTf)3/2-MeTHF can be proposed as a cheap, efficient, and environmentally sustainable reduction system for the synthesis of allylic alcohols.
PRO-FRAGRANCE COMPOUNDS
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Page/Page column 22, (2014/12/09)
A compound of Formula (I) wherein R1 represents a C3 to C20 hydrocarbon group derived from a fragrant alcohol of formula R1OH or from a fragrant aryl aldehyde or ketone of Formula (II), wherein: R2 is, independently, hydrogen atom, hydroxyl group, acetoxy group, -O(C=O)CH(CH3), optionally substituted C1-C6 alkyl group or C1-C6 alkoxy group, wherein any two of R2 may form an optionally substituted 5 or 6 membered ring, and R1 represents a radical derived from a fragrant alcohol of formula R1OH or from a fragrant aldehyde or from a fragrant aryl aldehyde or ketone of formula (II). The compounds are useful for example as a precursor for the prolonged delivery or release of fragrant compounds such as fragrant alcohols or aldehydes.
Selective reduction of dienes/polyenes using sodium borohydride/catalytic ruthenium(III) in various liquid amide aqueous mixtures
Babler, James H.,Ziemke, David W.,Hamer, Robert M.
, p. 1754 - 1757 (2013/04/10)
An efficient method to effect selective reduction of several structurally diverse dienes and an unsymmetrical triene is reported. The reduction is facile at 0 °C in a liquid amide aqueous solution containing sodium borohydride in the presence of 15 mol % ruthenium(III) chloride. The chemoselectivity of the reaction is controlled by proper choice of the liquid amide solvent.
New heterogeneous B(OEt)3-MCM-41 catalyst for preparation of α,β-unsaturated alcohols
Uysal, Burcu,Oksal, Birsen S.
, p. 3893 - 3911 (2015/06/08)
Grafting of boron tri-ethoxide on mesoporous MCM-41 resulted in a highly active catalyst for the Meerwein-Ponndorf-Verley (MPV) reduction and the catalyst denoted as B(OEt)3-MCM-41. Chemoselective reduction of α,β-unsaturated aldehydes and ketones to the corresponding α,β-unsaturated alcohols was achieved by MPV reduction reaction using a new B(OEt)3-MCM-41 catalyst. The prepared new heterogeneous catalyst, B(OEt)3-MCM-41, was characterized in detail by using XRD, 29Si NMR-, 11B NMR-, 13C NMR-, and TEM, N2 adsorption, and ICP-OES. The results demonstrated the successful homogenous distribution of the B(OEt)3 on the MCM-41 support. The heterogeneous B(OEt)3-MCM-41 catalyst, in comparison with the homogeneous B(O i Pr)3 and B(OEt)3 catalysts, displayed similiar catalytic activity in the MPV reduction of α,β-unsaturated aldehydes and ketones with alcohols as reductants. Reduced reaction times and very high selectivities for the unsaturated alcohols were obtained with the heterogenous catalyst compared with the homogeneous catalysts. The B(OEt)3-MCM-41 catalyst was found to be encouraging, as is is recyclable up to six cycles without any significant loss in its catalytic activity.
Comparison of heterogeneous B(OiPr)3-MCM-41 and homogeneous B(OiPr)3, B(OEt)3 catalysts for chemoselective MPV reductions of unsaturated aldehydes and ketones
Uysal, Burcu,Oksal, Birsen S.
experimental part, p. 204 - 216 (2012/10/18)
Boron tri-isopropoxide, B(OiPr)3, was immobilized on mesoporous material, MCM-41, and denoted as "B(OiPr) 3-MCM-41". The prepared new heterogeneous catalyst, B(O iPr)3-MCM-41, was characterized in details by using PXRD, FT-IR-, 11B NMR-, 29Si NMR-, 13C NMR-, TEM, EDX, N2 adsorption and ICP-OES. The results demonstrated the successful homogenous distribution of the B(OiPr)3 on the MCM-41 support. Heterogeneous B(OiPr)3-MCM-41 catalyst in comparison with the homogeneous B(OiPr)3 and B(OEt) 3 catalysts, display similiar catalytic activity in the Meerwein-Ponndorf-Verley (MPV) reduction of unsaturated aldehydes and ketones with alcohols as reductants. Reduced reaction times, higher rate constants and very high selectivities for the unsaturated alcohols were obtained with the heterogenous catalyst than the homogeneous catalysts. In most cases, there were no side products other than the desired alcohol. The B(OiPr) 3-MCM-41 catalyst was found to be encouraging as the catalyst is recyclable up to six cycles without any significant loss in its catalytic activity. This work enriches the family of heterogeneous MPV catalysts for chemoselective reductions of unsaturated aldehydes and ketones.
Bu4N[Fe(CO)3(NO)]-catalyzed hydrosilylation of aldehydes and ketones
Dieskau, Andre P.,Begouin, Jeanne-Marie,Plietker, Bernd
experimental part, p. 5291 - 5296 (2011/11/13)
The nucleophilic Fe complex Bu4N[Fe(CO)3(NO)] (TBAFe) has been used as a highly active catalyst for the mild hydrosilylation of a variety of functionalized aldehydes and ketones using inexpensive PMHS as stoichiometric reductant. The corresponding alcohols were obtained in good-to-excellent yields at low catalyst loadings of only 1 mol-% and reaction temperatures of 30-50 °C.
Applications of lanthanide trichloride hydrates prepared from mischmetall in Luche-type reduction
Lannou, Marie-Isabelle,Hélion, Florence,Namy, Jean-Louis
, p. 2707 - 2710 (2008/02/12)
An inexpensive alloy of light lanthanides, called Mischmetall, has been used in the preparation of a mixture of lanthanide trichloride hydrates. The use of this new type of material is described in Luche-type reductions. Georg Thieme Verlag Stuttgart.
