Опубликована: Ноя. 18, 2022
The synthesis of sulfochromeno [4,3-b] pyrrolidines is described. Under the catalysis 20 mol% Brønsted base and using 4Å molecular sieves as HF scavenger, imines derived from salicylaldehydes diethyl aminomalonate react with ethenesulfonyl fluorides through a tandem [3+2] cyclization-SuFEx click reaction to produce in high yields.
Язык: Английский
Chemistry - A European Journal, Год журнала: 2023, Номер 29(28)
Опубликована: Март 7, 2023
Abstract Asymmetric [3+2] cycloaddition reactions are fascinating and powerful methods for the synthesis of enantioenriched pyrrolidines up to four stereocentres. Pyrrolidines important compounds both biology organocatalytic applications. This review summarizes most recent advances in enantioselective by cycloadditions azomethine ylides using metal catalysis. It has been organized type catalysis used further arranged complexity nature dipolarophile. The presentation each reaction highlights their advantages limitations.
Язык: Английский
Процитировано
28
Colloids and Interface Science Communications, Год журнала: 2023, Номер 55, С. 100722 - 100722
Опубликована: Июнь 2, 2023
The unique characteristics of zirconium have made it susceptible to use in the pollutants purification. Although various zirconium-adsorbents been used remove fluoride, but no review article examines their perspective practical application. This reviewed defluoridation papers using Zr-adsorbents. modification adsorbents with was found a useful technique increase fluoride adsorption capacity. Researchers modified many materials like activated carbon, zeolite, and alumina by for efficient removal among them Zr-doped polypyrrole/Zr iodate composite (183.5 mg/g) CeO2-ZrO2 nanocages (175 great Zirconium improves chemistry morphology adsorption. Zr-materials were reusable mechanisms mostly electrostatic ion exchange. Due excellent feature zirconium, explorations can be continued provide higher ability eliminate or similar pollutants.
Язык: Английский
Процитировано
16
Carbohydrate Polymers, Год журнала: 2022, Номер 301, С. 120321 - 120321
Опубликована: Ноя. 11, 2022
Язык: Английский
Процитировано
22
Nature Communications, Год журнала: 2023, Номер 14(1)
Опубликована: Авг. 4, 2023
Herein, we report a copper(I)-catalyzed asymmetric 1,3-dipolar cycloaddition of azomethine ylides and 1,3-enynes, which provides series chiral poly-substituted pyrrolidines in high regio-, diastereo-, enantioselectivities. Both 4-aryl-1,3-enynes 4-silyl-1,3-enynes serve as suitable dipolarophiles while 4-alkyl-1,3-enynes are inert. Moreover, the method is successfully applied construction both tetrasubstituted stereogenic carbon centers spiro pyrrolidines. The DFT calculations also conducted, imply concerted mechanism rather than stepwise mechanism. Finally, various transformations started from pyrrolidine bearing triethylsilylethynyl group centered on alkyne achieved, compensates for inertness present reaction.
Язык: Английский
Процитировано
13
Chemical Science, Год журнала: 2023, Номер 14(20), С. 5460 - 5469
Опубликована: Янв. 1, 2023
A series of benzofulvenes without any electron-withdrawing substituents were employed as 2π-type dipolarophiles for the first time to participate in Cu(i)-catalyzed asymmetric 1,3-dipolar cycloaddition (1,3-DC) reactions azomethine ylides. An intrinsic non-benzenoid aromatic characteristic from serves a key driving force activation electron-rich benzofulvenes. Utilizing current methodology, wide range multi-substituted chiral spiro-pyrrolidine derivatives containing two contiguous all-carbon quaternary centers formed good yield with exclusive chemo-/regioselectivity and high excellent stereoselectivity. Computational mechanistic studies elucidate origin stereochemical outcome chemoselectivity, which thermostability these products is major factor.
Язык: Английский
Процитировано
11
Organic Letters, Год журнала: 2022, Номер 24(42), С. 7828 - 7833
Опубликована: Окт. 20, 2022
Chiral fluorinated amino esters and pyrrolidines are privileged scaffolds in synthetic chemistry exhibit unique biological properties. We report the facile preparation of these compounds through copper-catalyzed switchable defluoroalkylation [3 + 2] cycloaddition trifluoropropene an asymmetric fashion. The choice solvent chiral ligand was crucial for efficient transformation exquisite chemoselectivity pattern from identical starting materials that rapidly reliably incorporate gem-difluoroalkene trifluoromethyl (CF3) motifs to generate a diverse range enantioenriched building blocks good excellent yields with high induction.
Язык: Английский
Процитировано
15
Chinese Chemical Letters, Год журнала: 2024, Номер 35(12), С. 109665 - 109665
Опубликована: Фев. 23, 2024
Язык: Английский
Процитировано
3
Organic Chemistry Frontiers, Год журнала: 2024, Номер 11(21), С. 6177 - 6183
Опубликована: Янв. 1, 2024
o -Hydroxyaryl azomethine ylides react with ethenesulfonyl fluorides via a tandem [3 + 2] cycloaddition–SuFEx click process to produce sulfochromeno[4,3- b ]pyrrolidines in high yields.
Язык: Английский
Процитировано
3
Organic Letters, Год журнала: 2025, Номер unknown
Опубликована: Март 19, 2025
The sulfonyl group is able to polarize adjacent C=C bonds, but strength of the effect considerably varies with substituents (SO2X). In this report, we present asymmetric organocatalyzed conjugate addition 1,3-dicarbonyl compounds β-arylvinyl triflones (ArCH=CHSO2CF3). reaction runs under mild conditions 5 mol % tertiary amino-thiourea afford Michael-type adducts in high yields and enantioselectivities. Comparative experiments reveal that electron-withdrawing properties increase series SO2F ≪ SO2CF3 < SO2C4F9, latter approaching nitro group.
Язык: Английский
Процитировано
0
Organic Letters, Год журнала: 2023, Номер 25(37), С. 6818 - 6822
Опубликована: Сен. 1, 2023
Application of high-pressure conditions enables enantioselective Michael-type addition dialkyl malonates to β-arylethenesulfonyl fluorides. The reaction is efficiently catalyzed with 5 mol % tertiary amino-thiourea at 9 kbar. Chiral alkanesulfonyl fluorides are formed in yields up 96% and enantioselectivities 92%. Functionalization the adducts via sulfur fluoride exchange (SuFEx) desulfonylative cyclization demonstrated.
Язык: Английский
Процитировано
7