5441-04-3Relevant academic research and scientific papers
A general method for synthesis of cis-dicarbonyl epoxides through DBU/LiBr-cocatalyzed cyclization of α,β-dicarbonyl peroxides
Zong, Zhenzhen,Bai, Xiaohui,Lu, Shenglin,Li, Zhiping
supporting information, p. 3827 - 3831 (2016/08/02)
A general method for synthesis of cis-dicarbonyl epoxides is developed. The highly diastereoselective cyclization of α,β-dicarbonyl peroxides is achieved by DBU/LiBr cocatalysis. The coordination of lithium ion with two carbonyl groups is proposed for the
Malodour reducing composition and uses thereof
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, (2009/10/30)
The invention relates to a malodour reducing composition comprising: A) at least one phenylglycidate of formula (1): wherein: - R1 is a C1-C4 branched or linear alkyl group, - R2 is hydrogen or methyl, and - R3 is hydrogen, a C1-C4 branched or linear alkyl group or a methoxy group, and B) at least one 1,2 diketone of formula (2) or (3): wherein: - R4, R5 and R7 may be independently, a C1-C5 linear or branched alkyl or alkenyl group; - R6 is a (C1-C5) alkylidene; - R4 and R5 may also form a C4-C7 saturated or unsaturated alicyclic or heterocyclic ring structure, optionally substituted by (C1-C4) alkyl groups; - R6 and R7 may also form a C4-C7 unsaturated, alicyclic or heterocyclic ring structure optionally substituted by (C1-C4) alkyl groups; the weight ratio of glycidate A to 1,2 diketone B being from 1:99 to 99:1. The invention also relates to the fragrance compositions and consumer products containing this malodour reducing composition.
Design, synthesis, and evaluation of postulated transient intermediate and substrate analogues as inhibitors of 4-hydroxyphenylpyruvate dioxygenase
Lin, Yun-Loung,Huang, Jian-Lin,Wu, Chung-Shieh,Liu, Hung-Ge,Yang, Ding-Yah
, p. 1709 - 1713 (2007/10/03)
An epoxybenzoquinone, 4-hydroxyphenoxypropionic acid, and 2-hydroxy-3-phenyl-3-butenoic acid derivatives have been designed, synthesized, and evaluated for in vitro inhibition activity against 4-hydroxyphenylpyruvate dioxygenase (4-HPPD) from pig liver by the spectrophotometric enol-borate method. The biological data demonstrated that neither epoxybenzoquinone ester nor 2-hydroxy-3-phenyl-3-butenoic acid is an inhibitor of 4-HPPD. The most potent 4-HPPD inhibitor tested was 3-hydroxy-4-phenyl-2(5H)-furanone with an IC50 value of 0.5 μM, which may serve as a lead compound for further design of more potent 4-HPPD inhibitors.
A facile preparation of indium enolates and their Reformatsky-and Darzens-type reactions
Hirashita, Tsunehisa,Kinoshita, Kenji,Yamamura, Hatsuo,Kawai, Masao,Araki, Shuki
, p. 825 - 828 (2007/10/03)
Indium enolates were readily prepared by transmetalation of lithium enolates with indium trichloride, and were subsequently reacted with aldehydes to give β-hydroxy esters in high yields. Indium α-bromo enolates were also prepared and reacted with carbonyl compounds to give Darzens-type α,β-epoxy carbonyl products. The Royal Society of Chemistry 2000.
Asymmetric induction in Darzens condensation by means of (-)-8-phenylmenthyl and (-)-menthyl auxiliaries
Takagi, Ryukichi,Kimura, Jyunji,Shinohara, Yoshihiro,Ohba, Yuko,Takezono, Kyoko,Hiraga, Yoshikazu,Kojima, Satoshi,Ohkata, Katsuo
, p. 689 - 698 (2007/10/03)
Asymmetric Darzens condensation of benzaldehyde and various ketones has been investigated. The condensation of acetophenone, propiophenone and symmetric ketones with (-)-8-phenylmenthyl halogenoacetates 3a,b afforded the corresponding glycidic esters cis-12, cis-13 and 15-19 in 77-96% de, respectively, as the major products. Aza-Darzens condensation between N-benzylideneaniline and 3a occurred to give the trans-aziridine 21 as the major isomer in >85% de. The stereochemistry of the major diastereoisomers of cis-12 and 18 was confirmed by their conversion into the known optically active diols 22 and 24. The configuration of the major product of cis-12 was determined to be 2R,3R and that of 18 to be 2R. The geometric and disastereofacial selectivities were understandable in terms of the open-chain or non-chelated antiperiplanar transition state model in the initial aldol-type reaction.
Asymmetric Darzens condensation of ketones with α-chloroacetates by means of (-)-8-phenylmenthyl auxiliary
Ohkata, Katsuo,Kimura, Jyunji,Shinohara, Yoshihiro,Takagi, Ryukichi,Hiraga, Yoshikazu
, p. 2411 - 2412 (2007/10/03)
The Darzens condensation of symmetric and unsymmetric ketones with (-)-8-phenylmenthyl α-chloroacetate diastereoselectively affords glycidic esters in 77-94% de; the stereochemistry [(2R,3R) configuration] of the product is understandable in terms of π-π interaction in the open transition state model.
Metal Exchange between an Electrogenerated Organonickel Species and Zinc Halide: Application to an Electrochemical, Nickel-Catalyzed Reformatsky Reaction
Conan, Annie,Sibille, Soline,Perichon, Jacques
, p. 2018 - 2024 (2007/10/02)
The mechanism of the electroreductive coupling of α-chloro esters or α-chloro nitriles with carbonyl compounds by the means of a sacrificial zinc anode and a nickel catalyst was elucidated by electroanalytical techniques.The mechanism involved reduction of a Ni(II) complex to a Ni(0) complex, oxidative addition of the α-chloro ester to the Ni(0) complex, and a Zn(II)/Ni(II) exchange, leading to an organozinc Reformatsky reagent.The electrosynthesis of various β-hydroxy esters, β-hydroxy nitriles, and 2,3-epoxy esters was successfully achieved under extremely mild conditions.
REACTION OF 4-SUBSTITUTED BENZALDEHYDES AND ACETOPHENONES WITH CHLOROACETONITRILE
Svoboda, Jiri,Kocfeldova, Zuzana,Palecek, Jaroslav
, p. 822 - 832 (2007/10/02)
Under conditions of phase-transfer catalysis or in homogeneous solution of potassium tert-butoxide the title compounds give stereoisomeric mixtures of substituted 2,3-epoxy nitriles III and IV.Alkaline hydrolysis of epoxy nitriles IV afforded the corresponding 2-arylpropanals in low yields.On treatment with methanol and potassium carbonate, epoxy nitriles III and IV were converted into epoxy esters in good yields.
The Use of Microorganisms in Organic Synthesis. IV. Microbiological Asymmetric Reduction of Methyl 3-Phenyl 2-Oxobutyrate
Akita, Hiroyuki,Furuichi, Akiya,Koshiji, Hiroko,Horikoshi, Koki,Oishi, Takeshi
, p. 1342 - 1348 (2007/10/02)
The synthesis of optically active α-hydroxy β-methyl esters V by means of microbiological reduction of the corresponding α-keto β-methyl esters IV was carried out.Methyl 3-phenyl-2-oxobutyrate 3 was found to be reduced by a variety of yeasts to the α-hydr
Dianions Derived from α-Halo Acids. The Darzens Condensation Revisited
Johnson, Carl R.,Bade, Thomas R.
, p. 1205 - 1212 (2007/10/02)
The dianions of α-halo carboxylic acids are readily generated by the addition of the acids to 2 equiv of lithium diisopropylamide at low temperatures.When the mixture warms to room temperature dimeric products are formed.When aldehydes and ketones were added to the cooled solutions of the dianions and the reaction mixtures were allowed to warm to room temperature, followed by acid quench, glycidic acids were formed.The glycidic acids, per se, were often too unstable to be isolated and purified but could be analyzed by conversion to their methyl esters withdiazomethane.When the reactions were quenched prematurely, α-chloro-β-hydroxy carboxylic acids were isolated.Homologated aldehydes and ketones were obtained from the glycidic acids by catalytic and thermal decarboxylation methods.
