- Synthesis of new unsaturated enynes, catalysed by copper (I) complexes
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The copper (I) catalysed substitution of allylic chlorides by alk-1-ynes leads to the synthesis of new terpene derivatives. An efficient synthesis of phytone is described.
- Mignani,Chevalier,Grass,Allmang,Morel
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Read Online
- Glycinoprenols: Novel Polyprenols Possessing a Phytyl Residue from the Leaves of Soybean
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Three novel polyprenols, named glycinoprenol-9, -10, and -11, in addition to ficaprenols were isolated from the leaves of soybean, Glycine max Merill.The glycinoprenols were found to possess a phytyl residue, four to six internal (Z)-prenyl residues, and a Z α-terminal residue aligned in that order on the basis of their IR, 1H NMR, 13C NMR, and mass spectral data.The configurations of two chiral centers in the phytyl residue were determined to be all R by a combination of chemical and spectroscopic methods.
- Suga, Takayuki,Ohta, Shinji,Nakai, Akinori,Munesada, Kiyotaka
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Read Online
- SYNTHESIS OF NEW UNSATURATED ESTERS, CATALYZED BY PALLADIUM-PHOSPHINE COMPLEXES
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The palladium-catalyzed addition of allylic chlorides to carbonucleophiles leads to the formation of new terpene derivatives.A facile and economical route of phytone is described.
- Mignani, G.,Grass, F.,Aufrand, M.,Morel, D.
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Read Online
- Oxidative Cleavage of Alkenes by O2with a Non-Heme Manganese Catalyst
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The oxidative cleavage of C═C double bonds with molecular oxygen to produce carbonyl compounds is an important transformation in chemical and pharmaceutical synthesis. In nature, enzymes containing the first-row transition metals, particularly heme and non-heme iron-dependent enzymes, readily activate O2 and oxidatively cleave C═C bonds with exquisite precision under ambient conditions. The reaction remains challenging for synthetic chemists, however. There are only a small number of known synthetic metal catalysts that allow for the oxidative cleavage of alkenes at an atmospheric pressure of O2, with very few known to catalyze the cleavage of nonactivated alkenes. In this work, we describe a light-driven, Mn-catalyzed protocol for the selective oxidation of alkenes to carbonyls under 1 atm of O2. For the first time, aromatic as well as various nonactivated aliphatic alkenes could be oxidized to afford ketones and aldehydes under clean, mild conditions with a first row, biorelevant metal catalyst. Moreover, the protocol shows a very good functional group tolerance. Mechanistic investigation suggests that Mn-oxo species, including an asymmetric, mixed-valent bis(μ-oxo)-Mn(III,IV) complex, are involved in the oxidation, and the solvent methanol participates in O2 activation that leads to the formation of the oxo species.
- Bennett, Elliot L.,Brookfield, Adam,Guan, Renpeng,Huang, Zhiliang,Mcinnes, Eric J. L.,Robertson, Craig M.,Shanmugam, Muralidharan,Xiao, Jianliang
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supporting information
p. 10005 - 10013
(2021/07/19)
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- An Efficient Alternative to the Total Synthesis of Isophytol
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An improved and alternative method for the total synthesis of isophytol from citral via using pseudoionone intermediate was developed and described in this manuscript. This alternative commercially viable approach involves six steps and it represents an alternative method commercially viable over existing published synthetic methods in the literature. This goal was achieved by developing and optimizing an efficient and high yield procedure for the synthesis of a key intermediate i.e. 6,10,14-trimethylpentadectrimethylpentadec-5-en-2-one, by reacting 2-methoxypro-pene with a tertiary alcohol (3,7,11-trimethyldodec-1-ene-3-ol). Isophytol was provided in 58-60% overall yield from citral with >99% purity, evaluated by TLC, GC, and NMR.
- Yerramreddy, Thirupathi R.,Yiannikouris, Alexandros
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p. 996 - 999
(2022/02/17)
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- Synthesis method and method for synthesizing plant alcohol, isoplant alcohol and geranyl geraniol by using intermediate farnesylacetone (by machine translation)
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The invention relates to a synthesis method of intermediate farnesyl acetone and a method for synthesizing vitamin E, vitamin K1, vitamin K2 side chain isovegetable alcohol, plant alcohol and geranyl geraniol by using farnesyl acetone, and concretely relates to hydrogenation of 5 - farnesyl -2 - acetone and farnesyl acetone through three Grignard reaction to obtain plant ketone. The farnesyl acetone reacts with the vinyl chloride Grignard reagent to obtain geranyl linalool, the aromatic leaf-based geraniol is rearranged under acid catalysis, or farnesyl acetone is directly reacted with the hydroxyl-protected 2 - chloroethanol Grignard reagent to obtain geraniol. The plant alcohol is reacted with the vinyl chloride Grignard reagent to obtain the plant alcohol, and the plant alcohol is directly reacted with the hydroxyl-protected 2 - chloroethanol Grignard reagent to obtain the plant alcohol. The method has the advantages of cheap and easily available starting materials, short synthetic process steps, low product cost and the like. (by machine translation)
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Paragraph 0061; 0084-0085
(2020/07/21)
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- SYNTHESIS OF ALKYL 2-ACETYL-5,9,13-TRIMETHYLTETRADECA-4,8,12-TRIENOATES AND DERIVATIVES BY A NON-CONTINUOUS PRODUCTION PROCESS
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The present invention relates to the manufacturing of a process of alkyl 2- acetyl-5,9,13-trimethyltetradeca-4,8,12-trienoates and alkyl 2-acetyl-9,13-di- methyl-5-methylenetetradeca-8,12-dienoate as well as 6,10,14-trimethylpenta- deca-5,9,13-trien-2-one and 10,14-dimethyl-6-methylenepentadeca-9,13-dien-2-5 one and 6,10,14-trimethylpentadecan-2-one.
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Page/Page column 13-17
(2019/07/13)
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- Method for preparing unsaturated ketone
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The invention discloses a method for preparing unsaturated ketone. According to the method, an unsaturated alcohol and 2-alkoxy propylene are adopted as raw materials, an acid resin in a fixed bed aremodified, a Saucy-Marbet reaction is carried out, and unsaturated ketone is synthesized with high selectivity and high yields. According to the method, the modified acid resin is adopted as a catalyst, the problem that a common acid resin is poor in catalysis effect is solved; in addition, a fixed bed reactor is adopted to catalyze reactions, separation of the catalyst from reaction products before and after reactions can be achieved, equipment corrosion and adverse influence of a great amount of acids upon later industrial aftertreatment can be avoided, and the method is an economic and efficient synthesis method.
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Paragraph 0042-0050
(2019/04/04)
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- Preparation method for high-purity tocopherol succinate salt
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The invention relates to the field of organic synthesis, specifically to a preparation method for tocopherol succinate salt. The preparation method for the tocopherol succinate salt provided by the invention comprises the following steps: hydrogenating dl-alpha-tocopherol in the presence of a precious metal catalyst, subjecting a hydrogenated product and succinic anhydride to an esterification reaction in the presence of alkali so as to prepare a tocopherol succinate intermediate; and subjecting the tocopherol succinate intermediate to salt-forming. The preparation method for the tocopherol succinate salt provided by the invention can effectively improve the purity of a target product, can effectively reduce the content of a single impurity, and can prepare a calcium salt product with a purity capable of reaching 99.9% or above.
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Paragraph 0050; 0051; 0052; 0053
(2018/09/11)
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- PROCESS FOR THE MANUFACTURE OF 6,10,14-TRIMETHYLPENTADECAN-2-ONE
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The present invention is directed to a process for the manufacture of 6,10,14- trimethylpentadecan-2-one ("C18-ketone") comprising the step of hydrogenating a mixture of (5E, 9E)-farnesylacetone and (5Z, 9E)- farnesylacetone with hydrogen in the presence of a catalyst, whereby the catalyst is capable of preferentially hydrogenating carbon-carbon double bonds over carbon-oxygen double bonds. Preferably the catalyst comprises a metal selected from the group consisting of palladium, platinum, rhodium, iridium and nickel and mixtures thereof.
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Page/Page column 11-12
(2017/07/08)
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- PROCESS FOR THE MANUFACTURE OF 6,10,14-TRIMETHYLPENTADECAN-2-ONE, ISOPHYTOL AND ALPHA-TOCOPHEROL
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The present invention is directed to a process for the manufacture of 6,10,14-trimethylpentadecan-2-one ( C18-ketone ) comprising the step of hydrogenating a mixture of (3E,5E,9E)-3,4-dehydrofarnesylacetone and (3Z,5E,9E)-3,4-dehydrofarnesylacetone with hydrogen in the presence of a catalyst, whereby the catalyst is capable of preferentially hydrogenating carbon-carbon double bonds over carbon-oxygen double bonds. Preferably the catalyst comprises a metal selected from the group consisting of palladium, platinum, rhodium, iridium and nickel and mixtures thereof. A process for the preparation of (2E,6E)-farnesal by selective oxidation of (2E,6E)-farnesol and a process for the manufacture of a mixture of (3E,5E,9E)-3,4-dehydrofarnesylacetone and (3Z,5E,9E)-3,4-dehydrofarnesylacetone from (2E,6E)-farnesal is also disclosed.
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Page/Page column 10; 12
(2017/07/01)
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- METHOD OF PRODUCING FARNESYL ACETONE
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The present invention relates to a process for preparing farnesyl acetone.
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Paragraph 0155; 0156
(2017/04/11)
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- A method for synthesizing basking shark alkane
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The invention discloses a novel method for chemically synthesizing pristane on the basis of a starting material isophytol. By the method, pristane is obtained by oxidizing isophytol and performing epoxidation, lewis acid open-loop reaction, sulfonylation, halogenation and reduction. Compared with a conventional synthesis method, the method has the advantages that the raw material is low in cost, high-pressure hydrogenation reaction is avoided, the problem of methyl transfer or cyclization isomerization caused by dehydration reaction in the conventional synthesis method is solved, and the method is suitable for the industrial production of pristane.
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Paragraph 0034-0038; 0053-0055; 0066-0068
(2020/05/05)
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- A method for synthesizing basking shark alkane
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The present invention discloses a novel method for chemically synthesizing pristane with isophytol as a starting material. Isophytol is used, and pristane is prepared through oxidation, a methyl Grignard reaction, sulfonylation, halogenation and reduction. The method in the present invention, as compared with the conventional synthesizing method, adopts cheap raw materials, avoids high pressure hydrogenation reactions, and solves the problems of methyl migration caused by a dehydration reaction or isomerization caused by cyclization in the conventional synthesizing method. The method of the present invention is suitable for industrial production of pristane.
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Paragraph 0034; 0038; 0055; 0064-0066
(2017/08/23)
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- PROCESS OF ASYMMETRIC HYDROGENATION OF KETALS AND ACETALS
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The present invention relates to a process of the asymmetric hydrogenation of a ketal of an unsaturated ketone or an acetal of an unsaturated aldehyde by molecular hydrogen in the presence of at least one chiral iridium complex. This process yields chiral compounds in a very efficient way and is very advantageous in that the amount of iridium complex can be remarkably reduced.
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Page/Page column 55; 61
(2014/07/08)
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- USING MIXTURES OF E/Z ISOMERS TO OBTAIN QUANTITATIVELY SPECIFIC PRODUCTS BY COMBINING ASYMMETRIC HYDROGENATION AND ISOMERIZATION
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The present invention relates to a process of manufacturing compound having stereogenic centres from a mixture of E/Z isomers of unsaturated compounds having prochiral double bonds. The hydrogenation product has a specific desired configuration at the stereogenic centres. The process involves an asymmetric hydrogenation and an isomerization step. The process is very advantageous in that it forms the desired chiral product from a mixture of stereoisomers of the starting product in an efficient way.
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Page/Page column 56; 57; 63
(2014/07/08)
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- (6R,10R)-6,10,14-TRIMETYLPENTADECAN-2-ONE PREPARED FROM 6,10,14-TRIMETYLPENTADECA-5,9,13-TRIEN-2-ONE OR 6,10,14-TRIMETYLPENTADECA-5,9-DIEN-2-ONE
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The present invention relates to a process of manufacturing (6R,10R)- 6,10,14-trimetylpentadecan-2-one in a multistep synthesis from a mixture of (5E,9E)-, (5E,9Z)-, (5Z,9E)- and (5Z.9Z)- isomers of 6, 10, 14-trimetylpentadeca- 5,9,13-trien-2-one or 6,10,14-trimetylpentadeca-5,9-dien-2-one. The process is very advantageous in that it forms in an efficient way the desired chiral product from a mixture of stereoisomers of the starting product.
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Page/Page column 43; 44; 45
(2014/07/08)
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- USING MIXTURES OF E/Z ISOMERS TO OBTAIN QUANTITATIVELY SPECIFIC PRODUCTS BY COMBINED ASYMMETRIC HYDROGENATIONS
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The present invention relates to a process of manufacturing compound having stereogenic centres from a mixture of E/Z isomers of unsaturated compounds having prochiral double bonds. The hydrogenation product has a specific desired configuration at the stereogenic centres. The process involves two asymmetric hydrogenation steps. The process is very advantageous in that it forms the desired chiral product from a mixture of stereoisomers of the starting product in an efficient way.
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Page/Page column 47; 48; 54
(2014/07/08)
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- Hydrogenation of ketones having at least a carbon-carbon double bond in the gamma-,delta-position
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The present invention relates in a first aspect to a process for hydrogenation of ketones having at least a carbon-carbon double bond in the γ, δ-position to the keto group by hydrogen in the presence of at least one chiral iridium complex having a specific structure and particularly a specific aromatic ligand. It has been shown that this process leads to a strong increase in preferential formation of a single isomer. The process is particularly suitable for the hydrogenation of γ, δ -unsaturated ketones which can be used as flavours and fragrances or for the preparation of vitamin E and its derivatives or of flavours and fragrances.
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Page/Page column 11-12
(2013/02/28)
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- METHOD FOR PRODUCING OXYGEN-CONTAINING COMPOUND
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[Problem] There is provided a method for producing an oxygen-containing compound safely and with improved reaction efficiency, in which an undesired peroxide is unlikely to be produced, and efficient heat exchange of the ozonization can be achieved. [Mean for solving the Problem] The method comprises an ozonization reaction step of continuously supplying, together with an organic compound, ozone having an oxygen content of less than 10% in a dissolved state in high-pressure carbon dioxide to an ozonization reaction section having a thin tubular shape, and reacting the ozone and the organic compound under conditions that suppress generation of oxygen due to thermal decomposition of the ozone, thereby continuously producing an ozonide; and a decomposition reaction step of continuously supplying the ozonide produced in the ozonization reaction step to a decomposition reaction section having a thin tubular shape, thereby continuously producing an oxygen-containing compound, the decomposition reaction step being provided in a manner continuous with the ozonization reaction step.
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Page/Page column 24
(2012/01/11)
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- Transport of ethyne in form of alpha-alkynols as ethyne precursors
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The present invention relates to a new method for a safe transport of ethyne in form of α-alkynols as precursors for ethyne. The new method comprises three steps. In a first step the synthesis of the α-alkynol(s) is performed by reacting ethyne with (a) carbonyl compound(s). The second step comprises the transport of the resulting α-alkynol(s) in a safe manner, whereas the safety requirements for this transport are not as high as for ethyne because α-alkynol(s) are normally classified for transportation as hazardous class 3. In the third step the α-alkynol(s) can be cleaved and the ethyne and the carbonyl compound(s) can be obtained in the cleavage reaction and can be separated to yield pure products for further applications.
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Page/Page column 6
(2008/06/13)
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- CLEAVAGE OF ALKYNEDIOLS
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The present invention relates to a process for the manufacture of a mixture of ketones of the formula I and II, wherein R1, R2, R3 and R4 are independently from each other C1-30-alkyl, by reacting an alkynediol of the formula III in the presence of a catalyst at a temperature of at least 500C and/or at a pressure of at most atmospheric pressure. In preferred embodiments of the invention the ketones of the formulae I and II are identical. Preferably the catalyst is a basic catalyst, most preferably selected from the group consisting of aqueous NaOH and aqueous KOH solutions, and KF on alu minium oxide. The alkynediol is most preferably selected from the group consisting of 2,6,9,13- tetramethyl-tetradeca-2, 12-dien-7-yne-6,9-diol, 2,6, 10, 13 , 17,21 -hexamethyl-docos- 11-yne-10,13-diol, 2,6,10,14,17,21,25,29-octamethyl-triacont-15-yne-14,17-diol, 3,7,10,14-tetramethyl-hexadeca-3,13-dien-8-yne-7,10-diol, 3,6-dimethyl-oct-4-yne-3,6-diol and 2,5-dimethyl-hex-3-yne-2,5-diol. Advantegeously the process of the present invention may be used in the processes for the manufacture of dehydrolinalool or dehydroisophytol to recycle at least one of the starting materials.
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Page/Page column 14
(2008/06/13)
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- PROCESS FOR THE PREPARATION OF SATURATED ALIPHATIC KETONES
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Saturated aliphatic ketones, e.g. hexahydropseudoionone, may be prepared by hydrogenating an olefinically unsaturated ketone, e.g. pseudoionone in a continuous fixed-bed mode in the absence of a solvent in the presence of a catalyst comprising a noble metal deposited on a carrier.
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Page/Page column 4-5
(2008/06/13)
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- Hydrogenation on granular palladium-containing catalysts: I. Hydrogenation of tertiary acetylene alcohols
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Commercial granular palladium catalyst (0.5% of Pd on γ-Al 2O3) was modified by treating with zinc acetate (type 1) or successively with zinc acetate and ammonia (type 2). The treatment significantly increased the hydrogenation selectivity for a triple bond into a double bond: to 85.3-93.1% with the type 1 catalyst and to 96.3-97.8% with the type 2 catalyst. A construction of an autoclave with a fixed bed of the granular catalyst is described.
- Tolkacheva,Kislyi,Taits,Semenov
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p. 150 - 152
(2007/10/03)
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- Intermediates for use in the preparation of vitamin E
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Novel intermediate compounds which can be used in the preparation of phytone and Vitamin E and a process for the preparation thereof. A process for the preparation of phytone and Vitamin E from these compounds is also claimed.
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- Process for the preparation of phytone and novel intermediates thereof
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Novel intermediate compounds which can be used in the preparation of phytone and Vitamin E and a process for the preparation thereof. A process for the preparation of phytone from the intermediate compounds is also claimed.
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- Ozonolysis of alkenes and study of reactions of polyfunctional compounds. LIX. New approach to synthesis of isophytol and (E,E)-geranyllinalool, isoprenoid synthons for the α-tocopherol and (E,E)-α-tocotrienol
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A new approach was developed to the synthesis of racemic isophytol and (E,E)-geranyllinalool starting from a product of partial ozonolysis of (E,E,E)-l,5,9-cyclododecatriene.
- Odinokov,Akhmetova,Savchenko,Mallyabaeva,Lobanova
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p. 1099 - 1101
(2007/10/03)
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- A New Method for the Stereochemical Analysis of Acyclic Terpenoid Carbonyl Compounds
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A new method for the determination of the enantiomeric and diastereoisomeric composition of terpenoid carbonyl compounds is presented.Separation of the diastereomeric (+)-L-diisopropyl-tartrate acetals derived from dihydrocitronellal (6), hexahydropseudoionone (3), hexahydrofarnesal (7), and hexahydrofarnesylacetone (4), the C10, C13, C15, and C18 intermediates in various syntheses of naturally occuring tocopherols and vitamin K1, can be achieved by capillary GC on a cyanopropylsilicon-coated glass column under standardized conditions.This technique, presenting a significant improvment over existing methodologies, is considered to be particularly useful for the analysis of highly enriched samples, typically obtained by present-day asymmetric synthesis.With reproducibilities of +/- 0.3 percent, and therefore, safe for routine analysis, the complete stereochemical characterization of terpenoids with 15 and 18 C-atoms bearing two stereogenic centres is performed in a single operation for the first time.
- Knierzinger, Andreas,Walther, Willy,Weber, Beat,Mueller, Robert Karl,Netscher, Thomas
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p. 1087 - 1107
(2007/10/02)
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- 1,3,5-nonatriene derivatives, their preparation and their use
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1,3,5-Nonatriene derivatives of formula: STR1 in which R1 and R2, together with the carbon atom to which they are linked, form a carbonyl group, or each of R1 and R2 denotes alkoxy or R1 and R2 together form an alkylenedioxy radical, which may be made by reaction of a butadiene derivative of formula: STR2 in which R is alkyl or phenyl, with a butanal ketoacetal of 10 formula: STR3 followed by reaction of the product with a halomethyltriphenylphosphonium halide, are useful intermediates e.g. for the production of phytol.
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- Synthesis of Phytone Using Acetylbutyrolactone
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The Grignard reagent (II) from 2-(3'-chloropropyl)-2-methyl-1,3-dioxolane on reaction with methylheptenone (I) gives the tertiary alcohol (III), which on dehydration followed by hydrogenation gives hexahydropseudoionone (V).Repetition of the same sequence of reaction on V and IV gives phytone (VII) in quantitative yield.
- Kulkarni, Sheshgiri N.,Phadke, A. S.
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p. 685 - 686
(2007/10/02)
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- Microbial Oxidation of Isoprenoid Alkanes, Phytane, Norpristane and Farnesane
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Rhodococcus sp.BPM 1613, a pristane oxidizing microorganism, grows on isoprenoid hydrocarbons such as phytane (2,6,10,14-tetramethylhexadecane), norpristane (2,6,10-trimethyl-pentadecane) and farnesane (2,6,10-trimethyldodecane) as the sole carbon source, resulting in accumulation of oxidation products in the culture broth.The oxidation products of phytane, norpristane and farnesane in the respective culture broth were isolated and purified by the use of silica gel column chromatography.Their chemical structures were determined by instrumental analyses such as IR, NMR and mass spectrometry.The oxidation products of phytane were identified as 2,6,10,14-tetramethyl-1-hexadecanol and 2,6,10,14-tetramethylhexadecanoic acid, the product of norpristane as 2,6,10-trimethyl-1-pentadecanol, and that of farnesane as 2,6,10-trimethyl-1-dodecanol.All these oxidation products were either monoalcohols or monocarboxylic acids derived through oxidation of the isopropyl terminus of each alkane.In addition, the relationship between the terminal structure of isoprenoid hydrocarbons and microbial oxidation was explored on the basis of these results.
- Nakajima, Kenji,Sato, Akio,Takahara, Yoshimasa,Iida, Takeo
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p. 1993 - 2002
(2007/10/02)
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- Process for the preparation of α,δ-diethylenic carbonyl compounds
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α,δ-Diethylenic carbonyl compounds of the formula STR1 are made by an oxy-Cope rearrangement of an acetylenic alcohol of the formula STR2 in the presence of a catalyst based on a metal of Group Ib of the periodic table or palladium. In the formulae (I) and (II), R1, R2, R3 and R4, which may be identical or different, each denote a hydrogen atom or a hydrocarbon radical R2 and R3 being capable together of forming an alkylene radical (--CH2 --)n in which one or more carbon atoms may be substituted by one or more alkyl radicals containing 1 to 4 carbon atoms, n is 3 to 20 inclusively and R5 denotes a hydrogen atom.
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- Synthesis of Phytone and Phytol through Prins Reaction of Norphytene and its Isomer
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Prins reaction on 2,6-dimethyloct-2-ene (IIa) using paraformaldehyde furnishes 2-isopropenyl-5-methylheptanol (IIIa) which on periodate oxidation or ozonolysis followed by Jones' oxidation gives the acid (Va).The latter (Va) upon pyrolysis affords 6-methyl-2-octanone (VIa).Similarly, norphytene isomer (IIb) furnishes phytone (VIb) through IIIb, IVb and Vb.Norphytene (Ib) on Prins reaction gives mainly E-phytol as one of the products.
- Kamath, S. V.,Rangaishenvi, M. V.,Phadke, A. S.,Kulkarni, Sheshgiri N.
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p. 1008 - 1009
(2007/10/02)
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- ORGANIC SYNTHESES WITH SULFONES (PART XXVIII) ;SYNTHESIS OF TERPENOID COMPOUNDS BY WAY OF MICHAEL ADDITION REACTIONS TO CONJUGATED DIENYL SULFONES.
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Michael additions of ethanol and ketones to allyl-dienyl sulfones yielded di-allylic sulfones which were transformed into isoprenoid compounds by either Ramberg-Baecklund reaction or thermolysis.
- Julia, M.,Lave, D.,Mulhauser, M.,Ramirez-Munoz, M.,Uguen, D.
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p. 1783 - 1786
(2007/10/02)
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- Enamines: Part II - A New Synthesis of Norphytene
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A three-step synthesis of norphytene (I) starting from rhodinal (VII) via the key intermediate (III) is described.
- Rangaishenvi, M. V.,Kamath, S. V.,Bapat, B. V.,Hiremath, S. V.,Kulkarni, Sheshgiri N.
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p. 398 - 399
(2007/10/02)
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- 2-HYDROXYMETHYL-4-PHENYLTHIO-1-BUTENE AS A KEY COMPOUND FOR TOTAL SYNTHESIS OF ACYCLIC TERPENOIDS
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A new total synthesis of myrcene, citral, squalane, and isophytol employing 2-hydroxymethyl-4-phenylthio-1-butene as a starting material is described.
- Mandai, Tadakatsu,Yamaguchi, Hirofumi,Nishikawa, Kengo,Kawada, Mikio,Otera, Junzo
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p. 763 - 764
(2007/10/02)
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- Synthesis of Phytol
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Ethyl 3,7,11-trimethyldodecanoate (IV), obtained from geranylacetone (II) by modified Wittig condensation with ethyl diethylphosphonoacetate followed by catalytic hydrogenation, on LAH reduction yields the carbinol (V).V on alkylation through its mesylate with ethyl monosodioacetoacetate and subsequent decarbethoxylation with alkoholic KOH affords 6,10,14-trimethylpentadecan-2-one (VIII).VIII on treatment with vinylmagnesium bromide followed by treatment with PTS in acetic anhydride and glacical acetic acid yields 3,7,11,15-tetramethyl-2(E)-hexadecen-1-ol acetate (X) which on saponification furnishes phytol (I).
- Vig, O. P.,Bari, S. S.,Vig, Rashmi,Dua, D. M.
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p. 453 - 455
(2007/10/02)
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