25988-32-3Relevant articles and documents
Reactions of a tungsten-germylyne complex with α,β-unsaturated ketones: Complete cleavage of the W/Ge bond and formation of two types of η3-germoxyallyl tungsten complexes
Fukuda, Tetsuya,Hashimoto, Hisako,Tobita, Hiromi
, p. 80 - 83 (2014)
Germylyne complex Cp(CO)2W/Ge{C(SiMe3)3} (1) reacted with two molecules of RC(O)CH=CH2 (R = Me, Et) to give η3-allyl complexes, in which an oxagermacyclopentene framework was bound to an η3-allyl ligand through an oxygen atom. In the reaction with α-Me-substituted MeC(O)C(Me)=CH2, 1 reacted with only one molecule of the substrate to give another type of η3- allyl complex, in which a five-membered oxagermacyclopentenyl ring was coordinated to the W center in an η3 fashion. Both reactions resulted in unprecedented complete cleavage of a W/Ge triple bond.
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Jacob,P.,Brown,H.C.
, p. 7832 - 7833 (1976)
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Bienvenue,A.,Duchatellier,B.
, p. 833 - 843 (1972)
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Kinetics of the Unimolecular Elimination of Chlorobutanones in the Gas Phase
Chuhani, Gabriel,Hernandez A, Jose A.
, p. 4139 - 4141 (1981)
The gas-phase unimolecular elimination of 3-chloro-3-methyl-2-butanone has been investigated, in a static system and seasoned vessel, over the temperature range of 340-395 deg C and the pressure range of 60-190 torr.The reaction is homogeneous and unimolecular, follows a first-order rate law, and is invariable in the presence of cyclohexane, a radical-chain inhibitor.The products are isopropenyl methyl ketone and hydrogen chloride.The rate coefficients are given by the Arrhenius equation log k1 (s-1) = (12.56+/-0.31)-(190.8+/-3.7) kJ mol-1 (2.303RT)-1.When primary, secondary, and tertiary chlorobutanones are compared the presence of acetyl at the Cβ-Cl bond causes a significant rate enhancement due to the -M effect.However, if this substituent is at the Cα-Cl bond , deactivation in rate of elimination of these compounds is observed.The present work could well provide a general view on the effect of the acetyl substituent at the Cα-Cl and Cβ-Cl bonds in the molecular elimination of haloketones in the gas phase.
Cassis and Green Tea: Spontaneous Release of Natural Aroma Compounds from β-Alkylthioalkanones
B?ttig, Sarah,Bochet, Christian G.,Egger, Timothy,Flachsmann, Felix,Gey, Olga
, (2021/10/19)
In depth headspace analysis of the slow degradation of β-alkylthioalkanones in ambient air led to the discovery of a novel δ-cleavage pathway, by which β-mercaptoketones are released. Since β-mercaptoketones are potent natural aroma compounds occurring in many fruits, herbs and flowers, the discovery of an enzyme-independent molecular precursor for this class of high-impact molecules is of practical importance. Moreover, the formation of β-diketones and aldehydes by concomitant oxidation at the α-sulfur-position enhances the versatility of this class of aroma precursors. A mechanistic model is proposed which suggests that the oxidative degradation occurs through a novel Pummerer-type rearrangement of initially formed persulfoxides.
Hydroxyketones in the thiadiazine cycle formation
Pulatov, E. Kh.,Isobaev,Mavlonov
, p. 2475 - 2478 (2017/05/10)
Cyclocondensation of 1-hydroxyketones with thiosemicarbazide resulted in thiadiazines. Nitrate ester of 1-hydroxyketone reacted under similar conditions to give the corresponding thiosemicarbazone. In the case of bromoacetyl-substituted nitrate ester of 1-hydroxyketone, condensation proceeded via intramolecular reaction between the thiol and bromomethyl groups.
3-methyl-3-penten-2-one preparation method
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Paragraph 0019-0021, (2016/10/24)
The invention relates to a preparation method of 3-methyl-3-amylene-2-ketone. The preparation method comprises the steps of mixing butanone and a solid acid catalyst at 0-80 DEG C, adding acetaldehyde, fully mixing, reacting continuously, separating and purifying after reaction to obtain the 3-methyl-3-amylene-2-ketone, wherein the solid acid catalyst is highly-acidic dry type sulfonic acid group based polystyrene with H or sulfonic acid group based perfluorination cation exchange resin. According to the method, the solid acid catalyst is adopted, compared with the traditional synthetic method that strong acid and strong base are used, the method can greatly reduce the follow-up separation difficulty and environment pollution degree, no equipment corrosion is caused, and the product yield and the purity are high, therefore, the preparation method of 3-methyl-3-amylene-2-ketone is green and environment-friendly; and besides, no assisted solvent is adopted, the follow-up separation difficulty is reduced, the energy consumption and the production cost are low, and the industrial reliability is strong.
