- Macroreticular p-(ω-sulfonic-perfluoroalkylated) polystyrene ion-exchange resins: A new type of selective solid acid catalyst
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Macroreticular p-(ω-sulfonic-perfluoroalkylated) polystyrene (FPS) cation-exchange resins 3 have been synthesized by sequential p-perfluoroalkylation of macroreticular polystyrene (PS) 1 with ω-fluorosulfonylperfluorodiacyl peroxide 2, hydrolysis and acidification; the fluorinated mesoporous resins exhibited higher activity and selectivity than commercial Amberlyst 36 and Nafion NR50 in the cyclization of pseudoionone. The Royal Society of Chemistry 2005.
- Lin, Zhenghuan,Zhao, Chengxue
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- Cyclization of pseudoionone into α-Ionone over heteropolyacid supported on mesoporous silica SBA-15
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Cyclization of pseudoionone into α-ionone was performed over the series heteropolyacid supported on SBA-15 in liquid-phase at 363 and 373 K using a batch reactor. It has been demonstrated that the liquid-phase synthesis of α-ionone by pseudoionone cyclization can be efficiently achieved on heteropolyacid/SBA-15 materials. The high catalytic performance of PW 12/SBA-15 materials is due to their strong Bronsted acidity, high dispersion of active phase and also to absence of steric constraints for pseudoionone cyclization. PW12/SBA-15 catalysts are specially active and selective for this reaction giving predominantly α-ionone, as the main product, with high yield (about 60% at 373 K after 2 h) close to that obtained via the homogeneous synthesis. This catalytic system is more active and efficient in comparison with heteropolyacid supported on commercial silica. In order to achieve comparable amount of α-ionone, as is got for PW 12/SBA-15, belongs to apply five times more of the catalyst based on classical SiO2.
- Rachwalik,Michorczyk,Ogonowski
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Read Online
- ω-Sulfonic-perfluoroalkylated poly(styrene-maleic anhydride)/silica hybridized nanocomposite as a new kind of solid acid catalyst
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A new kind of ω-sulfonic-perfluoroalkylated poly(styrene-maleic anhydride)/silica hybrid nanocomposite FSMA/SiO2 has been synthesized under mild conditions by perfluoroalkylation of styrene-maleic anhydride copolymer (SMA) with ω-fluorosulfonylperfluorodiacyl peroxides (SFAP), and followed in turn by aminolysis using (3-aminopropyl)triethoxysilane (APTES), alkali hydrolysis, gelation with tetraethoxysilane (TEOS) and finally acidification. The hybrid solid acid FSMA/SiO2 with terminal perfluoroalkylsulfonic and carboxyl groups was characterized by FTIR, SEM, TEM, TGA, XPS, EDX, acidimetry and nitrogen sorption technique. Its pore structure, acid strength and acid amount were easily modulated by controlling the gelation and perfluoroalkylation conditions. The catalytic activity and selectivity, as well as reusability of FSMA/SiO2 were tested in three important reactions, namely, cyclization of pseudoionone, condensation of indole and esterification of benzoic acid. Owing to the higher exchange capacity than that of Nafion/SiO2, and the stronger acidity than that of Amberlyst-15, the nanocomposite FSMA/SiO2 showed higher activity and selectivity than these commercial solid acids in the reactions.
- Lin, Zhenghuan,Huang, Limei,Ling, Qidan,Chen, Hong,Zhao, Chengxue
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- Synthesis of ionones on solid Br?nsted acid catalysts: Effect of acid site strength on ionone isomer selectivity
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The effect of Br?nsted acid site strength on the liquid-phase conversion of pseudoionone to ionone isomers (α-, β- and γ-ionone) was studied on resin Amberlyst 35W, silica-supported heteropolyacid (HPAS) and silica-supported triflic acid (TFAS). Catalyst acidity was probed by temperature-programmed desorption of NH3 coupled with infrared spectra of adsorbed pyridine. The initial pseudoionone conversion rate followed the order: TFAS > Amberlyst 35W ≈ HPAS. Synthesis of the three ionone isomers occurred via a common cyclic carbocation intermediate formed from the activation of the pseudoionone molecule on Br?nsted acid sites. Initial ionone mixtures containing a α:β:γ isomer distribution of about 40:20:40 were formed, irrespective of the acid site strength. But the ionone mixture composition changed with the progress of the reaction because γ-ionone was consecutively converted to α-ionone on HPAS and Amberlyst 35W, whereas the stronger acid sites of TFAS converted γ-ionone to β-ionone.
- Díez,Apesteguía,Di Cosimo
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- Continuous preparation method of high-selectivity alpha-ionone
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The invention provides a continuous preparation method of high-selectivity alpha-ionone, pseudoionone is taken as a raw material, alpha-ionone is prepared under the condition of a catalyst system, thecatalyst system comprises a catalyst 1, a catalyst 2 and an auxiliary agent, the catalyst 1 is concentrated sulfuric acid or methanesulfonic acid, and the catalyst 2 is liquid organic carboxylic acid. Pseudoionone, a solvent and a catalyst system are uniformly mixed in a static mixer, then enter a pipeline reactor and react in the pipeline reactor, then the reaction liquid is discharged from an outlet of the pipeline reactor and enters a quenching stirring kettle to be quenched, and the reaction is ended. The synthesis process provided by the invention has the advantages of high catalytic efficiency, short reaction time, high alpha ionone content, continuous application of the catalyst and less three wastes, realizes continuous reaction, greatly saves the reaction time, operation and device cost, meets the requirements of green chemistry, and is suitable for industrial large-scale production.
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Paragraph 0033-0071
(2020/08/06)
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- Photocaged Hydrocarbons, Aldehydes, Ketones, Enones, and Carboxylic Acids and Esters that Release by the Norrish II Cleavage Protocol and Beyond: Controlled Photoinduced Fragrance Release
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Five families of caged fragrance compounds that allow the storage and release of the following small volatile organic molecules are described: terpene hydrocarbons, aldehydes, ketones, Michael-type α,β-unsaturated enones, and carboxylic acids and esters. These caged molecules are released by photoexcitation via carbonyl-directed hydrogen-transfer processes and subsequent C-C bond cleavage (Norrish Type II) or by didenitrogenation of diazirines.
- Griesbeck, Axel G.,Porschen, Bj?rn,Kropf, Christian,Landes, Agnieszka,Hinze, Olga,Huchel, Ursula,Gerke, Thomas
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p. 539 - 553
(2017/01/25)
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- Controlled release of encapsulated bioactive volatiles by rupture of the capsule wall through the light-induced generation of a gas
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The encapsulation of photolabile 2-oxoacetates in core-shell microcapsules allows the light-induced, controlled release of bioactive compounds. On irradiation with UVA light these compounds degrade to generate an overpressure of gas inside the capsules, which expands or breaks the capsule wall. Headspace measurements confirmed the light-induced formation of CO and CO2 and the successful release of the bioactive compound, while optical microscopy demonstrated the formation of gas bubbles, the cleavage of the capsule wall, and the leakage of the oil phase out of the capsule. The efficiency of the delivery system depends on the structure of the 2-oxoacetate, the quantity used with respect to the thickness of the capsule wall, and the intensity of the irradiating UVA light.
- Paret, Nicolas,Trachsel, Alain,Berthier, Damien L.,Herrmann, Andreas
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supporting information
p. 2275 - 2279
(2015/02/19)
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- PRO-FRAGRANCE COMPOUNDS
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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.
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Page/Page column 22
(2014/12/09)
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- Aromatic aldols and 1,5-diketones as optimized fragrance photocages
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Aromatic aldols and 1,5-diketones with abstractable γ-hydrogen atoms are highly photoactive cage molecules for the release of fragrance carbonyl compounds (aldehydes and Michael ketones, respectively). Aldols 3a-d are easily accessible by Mukaiyama addition and are cleaved to form the substrates with high quantum yields under solar radiation. By tuning the properties of the chromophores, a series of δ-damascone cages 5 were developed that can be used for selective and fast (5a,e) or slow (5b,d) release of fragrances under air and solar irradiation. The intermediates of the Norrish II process were observed by laser transient absorption spectroscopy.
- Griesbeck, Axel G.,Hinze, Olga,Goerner, Helmut,Huchel, Ursula,Kropf, Christian,Sundermeier, Uta,Gerke, Thomas
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experimental part
p. 587 - 592
(2012/06/30)
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- Gold-mediated synthesis of α-ionone
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A simple and convenient synthesis of α-ionone, an important component of flowers and fragrances, is reported. The key step in the formation of the α,β-unsaturated ketone moiety involves an NHC-AuI catalyzed Meyer-Schuster-like rearrangement of readily prepared propargylic esters. The complex [{Au(IPr)}2(μ-OH)][BF4] proved to be the most efficient catalyst leading to α-ionone in 70% yield from a propargylic benzoate. This optimized procedure represents a valuable and attractive alternative to classical methods leading to α,β- unsaturated ketones, such as the Wittig or aldol reactions.
- Merlini, Valentina,Gaillard, Sylvain,Porta, Alessio,Zanoni, Giuseppe,Vidari, Giovanni,Nolan, Steven P.
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scheme or table
p. 1124 - 1127
(2011/03/22)
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- A simple and versatile re-catalyzed meyer-schuster rearrangement of propargylic alcohols to α,β-unsaturated carbonyl compounds
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The development of a general catalytic procedure for the rapid and efficient 1,3-rearrangement of free secondary and tertiary propargylic alcohols to the corresponding α,β-unsaturated carbonyl compounds using available [ReOCl3(OPPh3)-(SMe2)] complex, was reported. The reaction was carried out under neutral environmental conditions with no racemization of potentially enolizable stereocenters with virtually complete E stereoselectivity. The reaction under dimethoxyethane, proceeded at the lower rate than in THF, but with reduced by-products and the yield obtained were highly significant. The reaction was reported to increase constantly at the expense of the (Z)-isomer 2b, where the double bong isomerization was attributed to a catalytic effect of the rhenium complex. The resulted new version of Meyer-Schuster rearrangement will find enormous application in organic synthesis to develop one-pot multistep reaction sequences.
- Stefanoni, Massimo,Luparia, Marco,Porta, Alessio,Zanoni, Giuseppe,Vidari, Giovanni
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body text
p. 3940 - 3944
(2009/12/03)
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- Process for the preparation of ionones and vitamin A, vitamin A derivatives, carotenes and carotenoids
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The present invention relates to a process for the preparation of β-ionones and/or α-ionones of the formulae II and III by acid catalyzed ring-closing of ψ-ionones of the formula I wherein R1 to R7 are independently selected from hydrogen and C1-C4-alkyl, R8 is selected from hydrogen and C1-C4-alkyl and the hydroxyl group, R9 and R10 are independently selected from hydrogen and C1-C4-alkyl or R9 and R10 form together the oxygen of a carbonyl group, whereby if R9 and R10 form together the oxygen of a carbonyl group no α-isomer is formed comprising: a) reacting a ψ-ionone according to formula I in presence of a concentrated Br?nsted-acid having a pKs 3, and an organic solvent that is substantially immiscible with the concentrated acid and with an diluted aqueous solution of said acid; b) hydrolysis of the reaction product obtained in step a) by addition of water; and phase separation into an organic phase comprising the β-ionone and/or the α-ionone of the formulae II and III and into an aqueous diluted acid phase; wherein water is added in the hydrolysis step b) in an amount to achieve an acid concentration in said aqueous diluted acid phase of 45 to 65 wt-%, that also can be easily integrated in a process for the preparation of vitamin A, a vitamin A derivative, a carotene or a carotenoid.
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Page/Page column 7-8
(2008/12/05)
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- Controlled light-induced release of volatile aldehydes and ketones by photofragmentation of 2-oxo-(2-phenyl)acetates
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The light-induced controlled release of fragrances from photolabile 2-oxo-(2-phenyl)acetates via Norrish Type II photofragmentation was evaluated by irradiation of the precursors in different solvents and on cotton in a typical fabric softener application. The desired photooxidation was found to work efficiently in water-based systems, and it tolerates the presence of oxygen. The formation of a certain amount of alcohol besides the desired aldehyde or ketone was attributed to further reaction of the photochemically released carbonyl compound, rather than to ester hydrolysis in an aqueous environment. Schweizerische Chemische Gesellschaft.
- Levrand, Barbara,Herrmann, Andreas
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p. 661 - 664
(2008/03/11)
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- 4,5-Didehydro-9-demethyl-9-halo-5,6-dihydroretinals and their 9-cyclopropyl and 9-isopropyl derivatives - Simple preparation of α-ionone derivatives and pure (all-E)-, (9Z)- and (11Z)-α-retinals
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α-Ionone and several of its chemically modified derivatives have been prepared in high yield in full isomeric purity by a Wadsworth-Emmons procedure using imino-phosphonate anion reagents. Starting from α-ionone, 5-(2′,6′,6′-trimethylcyclo-2′-hexen-1′-yl) -4-penten-2-yn-1-al could be prepared in a high yielding one-pot procedure. The corresponding (9-Cl-, 9-Br- and 9-I-α-ionylidene)acetaldehyde system could be obtained in one step in a quantitative mixture of (9Z) and (all-E) isomers by 1,4-nucleophilic addition reactions. The pure (all-E) and (9Z) isomers could be separated by simple column chromatography. The corresponding [(9Z)- and (all-E)-9-demethyl-9-fluoro-α-ionylidene]acetaldehydes could also be obtained in pure form by simple column chromatography. These α-ionylidene systems could be easily converted either into the (all-E)-4,5-didehydro-9- demethyl-9-halo-5,6-dihydroretinals or the corresponding (9Z) isomers in two steps. Similar mixtures of the corresponding (9Z,11Z)-and (9Z)-nitriles could be obtained by normal chemistry. The (9Z,11Z) isomer is the main component of this mixture, and could be obtained in pure form. Subsequent reduction with DIBAL-H and careful workup gave the pure (9Z,11Z)-9-halo-retinals. These (9Z,11Z) isomers show a similar extreme acid sensitivity to the corresponding 9-halo-β-retinals. α-Retinal and its 9-demethyl, 19,19-ethano and 19,19-dimethyl derivatives have been prepared in the (all-E), (9Z), and (11Z) isomeric forms in a similar manner. The corresponding β-retinal and its 9-demethyl derivative in the various isomeric forms are known. In this paper the 19,19-ethano- and 19,19-dimethyl-β-retinals in the (all-E), (9Z), and (11Z) isomeric forms are also reported. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.
- Wang, Yajie,Lugtenburg, Johan
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p. 3497 - 3510
(2007/10/03)
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- Remarkable reactivity of pyridinium chlorochromate adsorbed on neutral alumina under solvent-free conditions
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Pyridinium chlorochromate adsorbed on neutral alumina (PCC-Al2O3) under solvent-free conditions has been found to oxidize primary aliphatic alcohols to alkyl alkanoates whereas primary benzylic and primary allylic alcohols produce the corresponding aldehydes. Secondary aliphatic and aromatic alcohols produce ketones without isomerization and polymerization of double bonds, overoxidation and other side-reactions.
- Bhar, Sanjay,Chaudhuri, Subrata Kumar
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p. 3493 - 3498
(2007/10/03)
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- Practical Oppenauer (OPP) oxidation of alcohols with a modified aluminum catalyst
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(Matrix presented) Modified aluminum catalyst 2 was found to be highly effective for Oppenauer (OPP) oxidation of alcohols under mild conditions. For example, oxidation of carveol in toluene with t-BuCHO (1.2 equiv) as a hydride acceptor in the presence of 2 (1 mol %) proceeded smoothly at 21°C to give carvone in 94% yield after 1 h. A practical aspect of this system was highlighted by the facile OPP oxidation of terpenoids and steroids with 1.2-3.0 equiv of acetone and 2 (3-5 mol %).
- Ooi, Takashi,Otsuka, Hidehito,Miura, Tomoya,Ichikawa, Hayato,Maruoka, Keiji
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p. 2669 - 2672
(2007/10/03)
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- n-Butyltriphenylphosphonium dichromate: an efficient and selective oxidizing agent
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The preparation of n-butyltriphenylphosphonium dichromate is described. This reagent oxidizes alcohols to carbonyl compounds, thiols to disulfides and aromatic amines to azo compounds efficiently. Benzylic and allylic oximes are selectively oxidized to their corresponding carbonyl compounds in the presence of aluminium chloride.
- Baltork, I. Mohammadpoor,Sadeghi, M. M.,Mahmoodi, N.,Kharamesh, B.
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p. 438 - 441
(2007/10/03)
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- Composition containing body activated fragrance for contacting the skin and method of use
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Described is a fragrancing composition having fragrancing components that are not activated until, e.g., application to the skin of a human. The composition is alkaline or (if anhydrous) capable of producing an alkaline pH when in contact with water, prior to application, and includes (1) a vehicle such that when the composition is in contact with water, prior to application, the composition is at an alkaline pH; and (2) at least one potential fragrance that is at least one compound having little or no odor in the alkaline composition but which, e.g., is hydrolyzed in a lower pH environment to produce compounds having a relatively strong aroma. Upon application of the alkaline composition to the skin surface, the strong buffering capacity of the skin (the surface of which has a normal pH of 5.5-7.0) neutralizes alkalinity of the composition (lowers pH) so as to restore normal skin surface pH; the potential fragrance is then hydrolyzed at the lower pH to release the compound having relatively strong aroma. The potential fragrance can be incorporated as a component of a transparent (clear) deodorant stick composition for application to human axillary regions, the fragrance being released after application to the body.
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- Photochemical transformations of terpenoids in the presence of cyclodextrins
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The effect of complexation of terpene compounds with cyclodextrins on photolysis depends on the type of cyclodextrin and on the structure of the initial substrates. In some cases, only a change in the reaction rate is observed; in other cases, the complexation results in allylic rearrangements, hydride and acyl shifts, and cyclization with the formation of four-, five-, and six-membered cycles, whereas only cis-trans isomerization reactions are observed in the absence of complexation.
- Luzina,Tatarova,Korchagina,Salakhutdinov,Barkhash
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p. 183 - 193
(2007/10/03)
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- Epoxy-pyronene: Obtention of cyclocitrals from ionones and precursor of new terpenic compounds
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The selective obtention of epoxy-pyronene from δ-pyronene has been realized using metachloroperbenzoic acid. The isomerization of this epoxidic compound with Lewis and protonic acids and on active alumina has been studied leading to cyclocitrals. Ionones are obtained from epoxy-pyronene by homologation with various C3 units, in the presence of paratoluenesulfonic acid in order to obtain β-cyclocitral in situ. New terpenic compounds with the cyclogeranyl skeleton were obtained from epoxy-pyronene by reduction followed by homologation.
- Marc,Soulet,Serramedan,Delmond
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p. 3381 - 3388
(2007/10/02)
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- NEW DEVELOPMENTS OF THE WHARTON TRANSPOSITION
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The synthetically useful Wharton transposition can be improved by using a more adequate procedure in the critical step of the intermediate α-epoxyhydrazone cleavage.Either for stable hydrazones or unstable ones, the yield of the transposed allylic alcohol is increased by treatment under anhydrous conditions with highly basic reagents (KDA in the former case, NEt3 in the latter).
- Dupuy, C.,Luche, J. L.
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p. 3437 - 3444
(2007/10/02)
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- Nickel-Catalyzed Oxidation of Allylic Alcohols with K2S2O8
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NiSO4-K2S2O8 has been found to be an efficient catalytic system for the selective oxidation of allylic alcohols to the corresponding unsaturated carbonyl compounds in excellent yields.
- Yamazaki, Shigekazu,Yamazaki, Yasuyuki
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p. 1361 - 1364
(2007/10/02)
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- CYCLIZATION OF ACYLIC ISOPRENOIDS. I. MOLECULAR REARRANGEMENT OF GERANYLACETONES AND PSEUDOIONONES IN SUPERACIDS
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Stable carbocations were generated for the first time from geranylacetones and pseudoionones.They are intermediate compounds both of the acid-catalyzed transformations of these substances and of new previously unknown molecular rearrangements.Experimentally supported mechanisms were proposed for the investigated reactions.It was shown that variation of the various factors (the structural characteristics of the initial substrates, the acidity of the medium, the ratio of the acid and the initial substance, the generation temperature, and the thawing temperature of theacidic solution) makes it possible to control the structural and stereochemical selectivity of the electrophilic cyclization of acyclic isoprenoids.
- Gavrilyuk, O. A.,Korchagina, D. V.,Gatilov, Yu. V.,Mamatyuk, V. I.,Osadchii, S. A.,et al.
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p. 411 - 434
(2007/10/02)
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- Isolation of (2Z,4E)-&γ-Ionylideneethanol from Cercospora cruenta, a Fungus Producing (+)-Abscisic Acid
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(2Z,4E)-γ-Ionylideneethanol was separated from the mycelium of Cercospora cruenta, and its structure was confirmed by comparing the spectral data with those of an authentic specimen synthesized from γ-ionone.Gas chromatographic analysis of the extract showed the presence of a trace amount of (2Z,4E)-γ-ionylideneacetic acid.
- Oritani, Takayuki,Niitsu, Munetaka,Kato, Taku,Yamashita, Kyohei
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p. 2819 - 2822
(2007/10/02)
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- Composition of pseudoionone and ionone based on the isomers of citral from the chlorotelomer of isoprene
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It was shown that the synthetic isomers of citral, obtained from the monoadducts of the chlorotelomer of isoprene, only form E-enones during alkaline condensation with acetone.Under the influence of mineral acids the (3E, 5Z)- and (3E, 5E)-6,10-dimethyl-3,5,9-undecatrien-2-ones formed from the Z and E isomers of citral gave a mixture of α-, β-, and γ-ionones, hydroxyionone, and 10-hydroxypseudoionones.The isomeric (3E, 5Z)-(3E, 5E)6,8,8-trimethyl-3,5,9-decatrien-2-ones and (3E, 5E)-5,10-dimethyl-3,5,9-undecatrien-2-one, obtained from the skeletal isomers of citral, do not undergo cyclization under the indicated conditions.The isolated compounds were characterized by (13)C NMR spectroscopy.
- Siirde, K. E.,Erm, A. Yu.,Vyalimyae, T. K.,Lyiveke, I. A.,Leets, K.V.
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p. 2230 - 2235
(2007/10/02)
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- Production of ionones and irones by thermal rearrangement of propargylic alcohols
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Ionones and irones are produced by thermal rearrangement of novel propargylic alcohols, as follows: STR1 wherein R1 is a lower alkyl group, R2 is hydrogen or methyl and the dotted lines in the product formula reflect the existence of a double bond at either one or the other of the positions indicated.
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- Process for the production of unsaturated ketones
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There is disclosed a process for preparing unsaturated ketones especially terpenoid ketones, by subjecting a substituted propargyl alcohol of formula (II) STR1 wherein R is a group containing 1 or 2 substituted or unsubstituted alkyl- or alkylene units containing 4 carbon atoms each to a thermal treatment sufficient to rearrange its structure in order to obtain structurally isomeric unsaturated ketones of formula I STR2 wherein one of the substituents X3 and X4 is hydrogen and the other and Z2 together form a bond. The process can be effected in the presence of an isomerization catalyst, which leads to high percentage of α.β,γ.δ-unsaturated ketones. The ketones of formula I are useful as perfumes and as intermediates for the production of terpenoid compounds.
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