A Theoretical Examination of the Acid-Catalyzed and Noncatalyzed Ring-Opening Reaction of an Oxirane by Nucleophilic Addition of Acetate. Implications to Epoxide Hydrolases

2001 ◽  
Vol 123 (14) ◽  
pp. 3350-3357 ◽  
Author(s):  
Edmond Y. Lau ◽  
Zachary E. Newby ◽  
Thomas C. Bruice
Keyword(s):  
Nucleophilic Addition ◽  
Ring Opening ◽  
Epoxide Hydrolases ◽  
Theoretical Examination ◽  
Ring Opening Reaction ◽  
Acid Catalyzed

Design, synthesis and evaluation of structurally diverse ortho-acylphenol-diindolylmethane hybrids as anticancer agents

2022 ◽  
Author(s):  
Zhi-Gang Yin ◽  
Xiong-Wei Liu ◽  
Hui-Juan Wang ◽  
Min Zhang ◽  
Xiong-Li Liu ◽  
...  
Keyword(s):  
Carboxylic Acid ◽  
Anticancer Agents ◽  
Nucleophilic Addition ◽  
Ring Opening ◽  
Building Blocks ◽  
Efficient Synthesis ◽  
Design Synthesis ◽  
Pyrone Ring ◽  
Ring Opening Reaction ◽  
First Time

A highly efficient synthesis of structurally diverse ortho-acylphenol–diindolylmethane hybrids 3 using carboxylic acid-activated chromones as versatile synthetic building blocks is reported here for the first time, through 1,4-nucleophilic addition and followed by a decarboxylation and pyrone ring opening reaction process.

Synthesis of Azocane- and Oxocane-Annulated Furans by a [2+2] Photocycloaddition–Ring-Opening Cascade

Synthesis ◽  
2020 ◽  
Author(s):  
Thorsten Bach ◽  
Xinyao Li ◽  
Christian Jandl
Keyword(s):  
Double Bond ◽  
Uv Irradiation ◽  
Alkyl Group ◽  
Ring Opening ◽  
Cascade Reaction ◽  
Coumarin Derivatives ◽  
Ring Opening Reaction ◽  
Acid Catalyzed ◽  
Subsequent Acid

AbstractThe title compounds were synthesized from readily available quinolone and coumarin derivatives by a cascade reaction (12 examples, 90–98% yield). The cascade comprised a [2+2] photocycloaddition which occurred upon sensitized irradiation at λ = 420 nm (or direct UV irradiation at λ = 366 nm) and a subsequent acid-catalyzed ring-opening reaction. A variety of substituents are compatible with the conditions and a 3-alkyl group in the coumarin (or quinolone) is crucial to achieve a high chemoselectivity. Key to the success of the ring opening is the formation of a 4,5,5a-trihydrocyclobuta-2H-furan containing a strained bridgehead double bond which stems from the allenyl group tethered to the 4-position of the starting materials.

Regio- and Stereoselective Synthesis of a Novel Family of Unsaturated Compounds with the S–Se Bond and Their Cyclization to 2,3-Dihydro-1,4-thiaselenines

Synthesis ◽  
2019 ◽  
Vol 51 (08) ◽  
pp. 1832-1840 ◽  
Author(s):  
Svetlana Amosova ◽  
Andrey Filippov ◽  
Vladimir Potapov ◽  
Maxim Penzik ◽  
Nataliya Makhaeva ◽  
...  
Keyword(s):  
Ring Opening ◽  
Room Temperature ◽  
Stereoselective Synthesis ◽  
Reaction Times ◽  
Nucleophilic Attack ◽  
Selenium Atom ◽  
Efficient Synthesis ◽  
Reaction Conditions ◽  
Ring Opening Reaction ◽  
Acid Catalyzed

Regio- and stereoselective ring-opening reaction of 2-bromomethyl-1,3-thiaselenole with thiols proceeded as nucleophilic attack at the selenium atom of seleniranium intermediate affording unsaturated selanyl sulfides, (Z)-CH2=CHSCH=CHSeSR, in up to 93% yield. Dithiols were involved in this reaction giving symmetrical polyunsaturated compounds with two S–Se bonds in 70–75% yields. Efficient synthesis of 2-(organylsulfanyl)-2,3-dihydro-1,4-thiaselenines in 69–96% yields was developed by the acid-catalyzed cyclization of the unsaturated selanyl sulfides. Mild reaction conditions (room temperature) and short reaction times are important features of this methodology.

scholarly journals Theoretical study on the nucleophilic fluoroalkylation of propylene oxide with fluorinated sulfones

2013 ◽  
Vol 78 (4) ◽  
pp. 483-494
Author(s):  
Ling-Li Han ◽  
Tao Liu
Keyword(s):  
Gas Phase ◽  
Propylene Oxide ◽  
Nucleophilic Addition ◽  
Ring Opening ◽  
Theoretical Study ◽  
Addition Reactions ◽  
Ring Opening Reaction ◽  
Reactivity Order ◽  
Better Than ◽  
Good Agreement

The path of nucleophilic fluoroalkylation reaction of propylene oxide with PhSO2CYF- (Y=F,H, and PhSO2, respectively) in gas phase and in Et2O solvent were studied theoretically. The nucleophilic fluoroalkylation of propylene oxide with fluorinated carbanions was probed by the reactivity comparison between (benzenesulfonyl)monofluoromethyl anion (PhSO2CHF-), (benzenesulfonyl) difluoromethyl anion (PhSO2CF2-), and bis(benzenesul-fonyl) monofluoromethyl anion ((PhSO2)2CF-). The nucleophilicity reactivity order of PhSO2CYF- (Y = F, H, and PhSO2) is [(PhSO2)2CF-] > PhSO2CHF- > PhSO2CF2-, which indicates that introducing another electron-withdrawing benzenesulfonyl group is an effective way to significantly increase the nucleophilicity of the fluorinate carbanions. For comparison, we also studied the nucleophilic addition reactions of propylene oxide with chlorine substituted carbanion PhSO2CHCl-. The calculated results show that the nucleophilicity of PhSO2CYF- is better than that of PhSO2CHCl- for the ring opening reaction with propylene oxide. The calculated results are in good agreement with the available experiments.

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