116499-64-0Relevant articles and documents
Microwave assisted bi-functional activation of β-bromo-tert-alcohols
Kannan, Nandini,Rangaswamy, Manjunatha Javagal,Kemapaiah, Bettadaiah Bheemanakere
, p. 1405 - 1410 (2015)
Microwave-assisted dehydration-oxidation of β-bromo-tert-alcohols to afford 2,3-unsaturated ketones in good yield is reported. The reaction of substrates with DMSO in 1:1 ratio (w/v) is promoted by ZnS in a solvent-free condition. A concurrent bi-functional activation of trans-vicinal bromo- and hydroxyl groups with ZnS is elucidated. This is a new observation under microwave and applies to β-bromo-tert-alcohols derived from 1,4-disubstitued-1-cyclohexenes. It is very useful in the synthesis of 2,3-unsaturated ketones derived from monoterpenes which are valuable flavour compounds. [Figure not available: see fulltext.]
A 38 kDa allylic alcohol dehydrogenase from the cultured cells of Nicotiana tabacum
Hirata, Toshifumi,Tamura, Yoshitaka,Yokobatake, Naoyuki,Shimoda, Kei,Ashida, Yoshiyuki
, p. 297 - 303 (2000)
An NADP+-dependent alcohol dehydrogenase (allyl-ADH) was isolated from the cultured cells of Nicotiana tabacum. The allyl-ADH was found to be efficient for the dehydrogenation of secondary allylic alcohols rather than saturated secondary alcohols and it was specific for the S-stereoisomer of the alcohols. The enzyme catalyzed the reversible reaction whereby the carbonyl group of enones is reduced to the corresponding allylic alcohol or vice versa. Two possible primary structures of the allyl-ADH were deduced by the sequence analyses of full-length cDNAs (ally-ADH1 and ally-ADH2), which were cloned by the PCR method. These analyses indicated that the allyl-ADHs are composed of 343 amino acids-having the molecular weights 38 083 and 37 994, respectively, and they showed approximately 70% homology to the NADP+-dependent oxidoreductases belonging to a plant ζ-crystallin family. (C) 2000 Elsevier Science Ltd.
Stereoselective reduction of (R)-(-)-carvone with sodium dithionite in the presence of cyclomaltoheptaose (β-cyclodextrin) and its heptakis(2,6-di-O-methyl) derivative
Fornasier,Marcuzzi,Parmagnani,Tonellato
, p. 245 - 249 (1991)
The authors have studied the competition between l,4 and l,2-reduction of the conjugated enone (r)-(-)-carvone in the presence of cyclomaltoheptaose and its heptakis derivative using sodium dithionite as a reducing agent in aqueous sodium hydrogen carbonate with or without benzene. The spectrum of products namely the ketones and the alcohols expected from the non-selective reduction of an organic compound is shown.
Heteropoly acid catalysis for the isomerization of biomass-derived limonene oxide and kinetic separation of the trans-isomer in green solvents
Cotta, Rafaela F.,Martins, Rafael A.,Pereira, Matheus M.,da Silva Rocha, Kelly A.,Kozhevnikova, Elena F.,Kozhevnikov, Ivan V.,Gusevskaya, Elena V.
, (2019)
Terpenes are an abundant class of natural products, which is important for flavor and fragrance industry. Many acid catalyzed reactions used for upgrading terpenes still involve mineral acids as homogeneous catalysts and/or toxic solvents. Heteropoly acids represent a well-established eco-friendly alternative to conventional acid catalysts. As these reactions are usually performed in the liquid phase, solvents play a critical role for the process sustainability. In the present work, we developed a catalytic route to valuable fragrance ingredients, dihydrocarvone and carvenone, from limonene oxide by its isomerization using silica-supported tungstophosphoric acid as a heterogeneous catalyst and dialkylcarbonates as green solvents. The reaction pathway can be switched between dihydrocarvone and carvenone (obtained in 90% yield each) simply by changing the reaction temperature. In addition, we developed an efficient method for kinetic separation of trans-limonene oxide from commercial cis/trans-limonene oxide mixture and stereoselective synthesis of trans-dihydrocarvone.
Klabunovskii et al.
, (1972)
Selective carvone hydrogenation to dihydrocarvone over titania supported gold catalyst
Demidova,Suslov,Simakova,Simakova,Volcho,Salakhutdinov,Murzin
, p. 189 - 194 (2015)
Selective hydrogenation of natural carvone to industrially valuable dihydrocarvone was carried out at 100°C under hydrogen pressure over a 1.9wt.% Au/TiO2 catalyst. The gold catalyst has demonstrated high activity as well as stereo- and chemoselectivity in conjugated C=C double bond hydrogenation with predominant formation of trans-dihydrocarvone. The catalytic activity and trans-to cis-isomers ratio were shown to strongly depend on the solvent. In a range of C1 - C3 alcohol solvents both catalytic activity and trans-to cis-dihydrocarvone ratio increased following the order: 2-propanol a nearly complete carvone conversion (90%) after 13h in the case of methanol, with the trans-to cis-dihydrocarvone ratio being about 1.8. Based on the transition state theory a quantitative description of trans-to cis-dihydrocarvone ratio variations in different solvents was made.
REGIOSPECIFIC RDUCTION OF UNSATURATED CONJUGATED KETONES WITH SODIUM DITHIONITE UNDER PHASE TRANSFER CATALYSIS
Camps, Francisco,Coll, Jose,Guitart, Josefa
, p. 4603 - 4610 (1986)
Selective double bond reduction of unsaturated conjugated ketones has been achieved in excellent yields by use of sodium dithionite in a two phase benzene-water system with Adogen as phase transfer catalyst.However, this reduction was unsatisfactory for hydrophilic ketones; in this case, competitive reactions led to the predominant formation of water soluble sulfur derivatives, similar to those obtained in the reaction of unsaturated conjugated ketones with sodium dithionite in aqueous dimethylformamide.
ULTRASONICALLY IMPROVED REDUCTIVE PROPERTIES OF AN AQUEOUS Zn-NiCl2 SYSTEM - 2. REGIOSELECTIVITY IN THE REDUCTION OF (-)-CARVONE
Petrier, Christian,Luche, Jean-Louis
, p. 2351 - 2352 (1987)
While the previously described reductive system Zn-NiCl2 leads to the non-selective hydrogenation of the two olefinic bonds of (-)-carvone 1, the two selective hydrogenation products (+)-dihydrocarvone 2 and carvotaneacetone 3 are obtained in good yield with the same reagent under modified experimental conditions.
Novel concurrent redox cascades of (R)- and (S)-carvones enables access to carvo-lactones with distinct regio- and enantioselectivity
Iqbal, Naseem,Stewart, Jon D.,Macheroux, Peter,Rudroff, Florian,Mihovilovic, Marko D.
, p. 7389 - 7394 (2018)
Within this study, we investigated a one-pot enzymatic redox cascade composed of different enoate reductases (5 EREDs from diverse bacterial origins) and various Baeyer-Villiger monooxygenases (4 BVMOs) with complementary regioselectivity that enabled access to six out of eight carvo-lactone stereoisomers starting from readily available natural carvones. Applicability of this two-step cascade was demonstrated by preparative scale experiments yielding up to 76% of the desired chiral carvolactone.
C3 and C6 Modification-Specific OYE Biotransformations of Synthetic Carvones and Sequential BVMO Chemoenzymatic Synthesis of Chiral Caprolactones
Issa, Issa S.,Toogood, Helen S.,Johannissen, Linus O.,Raftery, James,Scrutton, Nigel S.,Gardiner, John M.
, p. 2983 - 2988 (2019)
The scope for biocatalytic modification of non-native carvone derivatives for speciality intermediates has hitherto been limited. Additionally, caprolactones are important feedstocks with diverse applications in the polymer industry and new non-native terpenone-derived biocatalytic caprolactone syntheses are thus of potential value for industrial biocatalytic materials applications. Biocatalytic reduction of synthetic analogues of R-(?)-carvone with additional substituents at C3 or C6, or both C3 and C6, using three types of OYEs (OYE2, PETNR and OYE3) shows significant impact of both regio-substitution and the substrate diastereomer. Bioreduction of (?)-carvone derivatives substituted with a Me and/or OH group at C6 is highly dependent on the diastereomer of the substrate. Derivatives bearing C6 substituents larger than methyl moieties are not substrates. Computer docking studies of PETNR with both (6S)-Me and (6R)-Me substituted (?)-carvone provides a model consistent with the outcomes of bioconversion. The products of bioreduction were efficiently biotransformed by the Baeyer–Villiger monooxygenase (BVase) CHMO_Phi1 to afford novel trisubstituted lactones with complete regioselectivity to provide a new biocatalytic entry to these chiral caprolactones. This provides both new non-native polymerization feedstock chemicals, but also with enhanced efficiency and selectivity over native (+)-dihydrocarvone Baeyer–Villigerase expansion. Optimum enzymatic reactions were scaled up to 60–100 mg, demonstrating the utility for preparative biocatalytic synthesis of both new synthetic scaffold-modified dihydrocarvones and efficient biocatalytic entry to new chiral caprolactones, which are potential single-isomer chiral polymer feedstocks.
(R)-(-)-carvone and (1R, 4R)-trans-(+)-dihydrocarvone from Poiretia latifolia vogel
Porto, Carla,Stu?ker, Caroline Z.,Mallmann, Anderson S.,Simionatto, Euclesio,Flach, Adriana,Do Canto-Dorow, Tais,Da Silva, Ubiratan F.,Dalcol, Ionara I.,Morel, Ademir F.
, p. 782 - 786 (2010)
The essential oils of Poiretia latifolia Vogel, native and cultivated leaves (Samples A and B, respectively) and native flowers (sample C), were obtained by hydrodistillation and analyzed by GC, GC/MS and chiral phase gas chromatography (CPGC). Twenty-four compounds were identified, representing 99.25, 99.26 and 99.23percent of the oils, respectively. The major constituents of the oils were the monoterpenes (S)-(-)-limonene (16.05, 27.60, 15.60percent, respectively), (1R, 4R)-trans-(+)-dihydrocarvone (18.05, 0.66 and 77.80percent, respectively) and (R)-(-)-carvone (61.05, 64.20 and 4.50percent, respectively). The essential oils were evaluated against some strains of Gram (+) and Gram (-) bacteria, and yeast, but displayed only modest antimicrobial activity.
Selective Catalytic Synthesis of 1,2- and 8,9-Cyclic Limonene Carbonates as Versatile Building Blocks for Novel Hydroxyurethanes
Maltby, Katarzyna A.,Hutchby, Marc,Plucinski, Pawel,Davidson, Matthew G.,Hintermair, Ulrich
, p. 7405 - 7415 (2020)
The selective catalytic synthesis of limonene-derived monofunctional cyclic carbonates and their subsequent functionalisation via thiol–ene addition and amine ring-opening is reported. A phosphotungstate polyoxometalate catalyst used for limonene epoxidation in the 1,2-position is shown to also be active in cyclic carbonate synthesis, allowing a two-step, one-pot synthesis without intermittent epoxide isolation. When used in conjunction with a classical halide catalyst, the polyoxometalate increased the rate of carbonation in a synergistic double-activation of both substrates. The cis isomer is shown to be responsible for incomplete conversion and by-product formation in commercial mixtures of 1,2-limomene oxide. Carbonation of 8,9-limonene epoxide furnished the 8,9-limonene carbonate for the first time. Both cyclic carbonates underwent thiol–ene addition reactions to yield linked di-monocarbonates, which can be used in linear non-isocyanate polyurethanes synthesis, as shown by their facile ring-opening with N-hexylamine. Thus, the selective catalytic route to monofunctional limonene carbonates gives straightforward access to monomers for novel bio-based polymers.
Acidity and Catalytic Activity of Iron(II) Sulfate Heat-treated at High Temperatures
Arata, Kazushi,Hino, Makoto
, p. 535 - 536 (1980)
Acidity and catalytic activity of FeSO4 calcined at 500-900 deg C were studied.The product obtained by calcination at 700 deg C showed maximum acidity at Ho1.5 and activity for isomerization of d-limonene oxide, polymerization of isobutyl vinyl ether and dehydration of 2-propanol.When calcined at 750 deg C the product showed no acidity or activity.
Synthesis and Biochemical Evaluation of Nicotinamide Derivatives as NADH Analogue Coenzymes in Ene Reductase
Falcone, Natashya,She, Zhe,Syed, Jebreil,Lough, Alan,Kraatz, Heinz-Bernhard
, p. 838 - 845 (2019/02/07)
Nicotinamide and pyridine-containing conjugates have attracted a lot of attention in research as they have found use in a wide range of applications including as redox flow batteries and calcium channel blockers, in biocatalysis, and in metabolism. The interesting redox character of the compounds’ pyridine/dihydropyridine system allows them to possess very similar characteristics to the natural chiral redox agents NAD+/NADH, even mimicking their functions. There has been considerable interest in designing and synthesizing NAD+/NADH mimetics with similar redox properties. In this research, three nicotinamide conjugates were designed, synthesized, and characterized. Molecular structures obtained through X-ray crystallography were obtained for two of the conjugates, thereby providing more detail on the bonding and structure of the compounds. The compounds were then further evaluated for biochemical properties, and it was found that one of the conjugates possessed similar functions and characteristics to the natural NADH. This compound was evaluated in the active enzyme, enoate reductase; like NADH, it was shown to help reduce the C=C double bond of three substrates and even outperformed the natural coenzyme. Kinetic data are reported.
