684-94-6Relevant academic research and scientific papers
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.
Monoozonolyses of Acyclic Conjugated Dienes
Griesbaum, Karl,Zwick, Gerhard
, p. 3041 - 3057 (2007/10/02)
Monoozonolyses of isoprene (1a), 2-methyl-3-phenyl-1,3-butadiene (1b), 2,3-diphenyl-1,3-butadiene (25), and 2,3,4,5-tetramethyl-2,4-hexadiene (34) have been examined in pentane and in methanol.The dienes 1a, b and 25 afforded all possible α,β-unsaturated monoozonides and α,β-unsaturated methoxy hydroperoxides, respectively, whereas diene 34 gave no ozonide and no α,β-unsaturated methoxy hydroperoxide.From the dienens 25 and 34, the corresponding monoepoxides have been formed additionally.The results allow some conclusions concerning the regioselectivity of ozone attack at the unsymmetrically substituted dienes 1a, b as well as concerning the cleavage directions of primary ozonides.
Halogen Epoxides, 7. Rearrangements during the Reaction of Substituted 2-Chloro- and 2,3-Dichlorooxiranes with Silver Tetrafluoroborate
Keul, Helmut,Pfeffer, Bernd,Griesbaum, Karl
, p. 2193 - 2204 (2007/10/02)
Reactions of tert-butyl-substituted and of isopropyl-substituted chlorooxiranes with silver tetrafluoroborate have been examined.Dehalogenations in the 2-positions of 2-chloro-2-tert-butyl- (5) and of 2-chloro-2-isopropyl-substituted oxiranes (35) occurred without changes of the carbon skeletons.By contrast, dehalogenations in the 2-positions of 2-chloro-3-tert-butyl- (12) and of 2-chloro-3-isopropyloxiranes (35) afforded partly rearranged products by 1,2-methyl- and/or 1,2-hydride shifts to the corresponding α-ketocarbenium ions.
FORMATION DE CETONES ETHYLENIQUES PAR ACTION D'ACIDE ACETYLSULFOACETIQUE SUR DES ALCENES
Loiseau, Andre-Michel,Luft, Robert,Zunino, Serge
, p. 144 - 152 (2007/10/02)
Monoalkyl- and 1,2-dialkylethylenes have a similar behaviour under the action of acetylsulfoacetic acid : the reaction does not necessarily stop after the formation of α- or β-enones, the yield of which is highly influenced by reaction time; thus, 1-acetoxy-1,3-dienes are identified in the case of α-enones.A different behaviour is shown by 1,1-dialkyl and trialkylethylenes, which can constitute an interesting source of highly branched enones.With this second group of alkenes, isomerisation of the alkene is sometimes observed prior to acetylation.Lastly, some alkenes undergo acetoxylation at the same time as acetylation.
Substitution and Elimination Reactions via One Electron Transfer Process. A New Olefin Synthesis from β-Nitro Sulfones
Ono, Noboru,Tamura, Rui,Nakatsuka, Tamon,Hayami, Jun-ichi,Kaji, Aritsune
, p. 3295 - 3300 (2007/10/02)
gem-Bromonitro compounds or gem-dinitro compounds couple with carbanions derived from α-cyano sulfones or α-carbonyl sulfones to give β-nitro sulfones.The nitro and sulfonyl groups are eliminated from the coupling products on treatment with reductive one electron transfer reagents to give α,β-unsaturated carbonyl compounds or nitriles.
