24767-69-9Relevant articles and documents
A Simple and Efficient Method for the Preparation of α-Halogenated Ketones Using Iron(III) Chloride and Iron(III) Bromide as Halogen Sources with Phenyliodonium Diacetate as Oxidant
Tang, Shi-Zhong,Zhao, Wenshuang,Chen, Tao,Liu, Yang,Zhang, Xiao-Ming,Zhang, Fu-Min
supporting information, p. 4177 - 4183 (2017/12/18)
α-Halogenated ketones are both unique structure moieties existing in biologically natural products and valuable synthetic intermediates for the preparation of functional molecules. An efficient and scalable method for the preparation of α-halogenated ketone using iron (III) chloride and iron (III) bromide as halogen sources with phenyliodonium diacetate as oxidant has been developed, featuring mild reaction conditions, environmentally friendly reagents, and wide substrate scope. Notably, the three-step synthesis of drug prasugrel was achieved using this developed method as a key step with 30% yield on gram-scale. Additionally, the reaction mechanism involving chloride cation was proposed based on some preliminary control experiments. (Figure presented.).
Theoretical and experimental studies on the Baeyer-Villiger oxidation of ketones and the effect of α-halo substituents
Grein, Friedrich,Chen, Austin C.,Edwards, David,Crudden, Cathleen M.
, p. 861 - 872 (2007/10/03)
The Baeyer-Villiger reactions of acetone and 3-pentanone, including their fluorinated and chlorinated derivatives, with performic acid have been studied by ab initio and DFT calculations. Results are compared with experimental findings for the Baeyer-Villiger oxidation of aliphatic fluoro and chloroketones. According to theoretical results, the first transition state is rate-determining for all substrates even in the presence of acid catalyst. Although the introduction of acid into the reaction pathway leads to a dramatic decrease in the activation energy for the first transition state (TS), once entropy is included in the calculations, the enthalpic gain is lost. Of all substrates examined, pentanone reacts with performic acid via the lowest energy transition state. The second transition state is also lowest for pentanone, illustrating the accelerating effect of the additional alkyl group. Interestingly, there is only a small energetic difference in the transition states leading to migration of the fluorinated substituent versus the alkyl substituent in fluoropentanone and fluoroacetone. These differences match remarkably well with the experimentally obtained ratios of oxidation at the fluorinated and nonfluorinated carbons in a series of aliphatic ketones (calculated, 0.3 kcal/mol, observed, 0.5 kcal/mol), which are reported herein. The migration of the chlorinated substituent is significantly more difficult than that of the alkyl, with a difference in the second transition state of approximately 2.6 kcal/mol.
THE CHLORINATION OF KETONES USING TRIMETHYLCHLOROSILANE AND DIMETHYLSULFOXIDE WITH BROMIDE ION CATALYSIS
Fraser, Robert R.,Kong, Fanzuo
, p. 1071 - 1078 (2007/10/02)
Chlorination using trimethylchlorosilane and dimerthylsulfoxide with bromide ion catalysis afforded almost quantitative yields for 1,3-diphenylacetone, benzoylacetone and propiophenone, and acceptable yields for acetophenone, acetylacetone and cyclohexanone.
α-Oxy(oxo) sulfides and ethers
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, (2008/06/13)
Described are α-oxy(oxo) sulfides and ethers having the generic structure: STR1 wherein X is one of: STR2 Z is one of sulfur or oxygen; when R1 and R2 are taken separately, R1 is hydrogen or methyl, and R2 is methyl; and when R1 and R2 are taken together, R1 and R2 form phenyl moieties; and Y is one of C1 -C4 alkyl, C3 or C4 alkenyl, acetyl, methoxycarbonylmethyl, or 1,3-diethylacetonyl. Addition of one or more α-oxy(oxo) sulfides and ethers to foodstuff flavorings or foodstuffs is indicated to produce the following aroma and flavor characteristics, in the alternative or taken together: Aroma Green/spicey, Sweet, Fruity, Fresh/fruity, Gooseberry, Concord grape, Grape, Almond, Nutty, Cereal-like, Lachrymatory onion-like, Oniony, Green onion-like, Leek, Broccoli-like, Grapefruit, Celery stalk-like, Floral, Rosey, Woody, Blackcurrant, Buchu leaf oil-like, Citronellal-like, Neroli-like, Bergamot-like, Violet leaves-like, Jasmin-like, Melony, Cucumber-like, Green, Vegetable, Sweet/floral. Flavor Spicey, Sweet, Fruity, Milk caramel-like (dulce de leche-like), Gooseberry, Broccoli-like, Nutty, Cereal-like, Oniony, Grape, Concord grape, Citrusy, Grapefruit-like, Green fruit-like, Mandarin-like, Petitgrain-like, Blackcurrant, Minty, Astringent, Coriander-like, Green, Piney, Citronellal-like, Violet leaves-like, Melony, Green fruit-like, Cucumber, Green, Floral, Floral/green, Vegetable, Garlic With lasting mouthfeel and with, in many cases, an oniony aftertaste. The compounds of our invention are useful in augmenting or enhancing the flavor and aroma nuances of berry flavors, cereal-like flavors, nut flavors, broccoli flavors, onion flavors, citrus flavors (including neroli, bergamot, lime), jasmin flavors, grapefruit flavors, concord grape flavors, blackcurrant flavors, milk caramel flavors (e.g., dulce de leche-like flavors), vegetable flavors, cucumber flavors, celery flavors and spice flavors. Addition of a number of these α-oxy(oxo) sulfides and ethers in perfumes, colognes or perfumed articles imparts thereto sweet, green, floral, herbal, vegetative, basil-like, minty, melony, grapefruit, fruity and alliaceous aromas with yara, neroli and/or verdima-like nuances.
