Generation of Axially Chiral Fluoroallenes through a Copper-Catalyzed Enantioselective β-Fluoride Elimination DOI
Thomas J. O’Connor, Binh Khanh, Jordan Nafie

et al.

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(34), P. 13759 - 13768

Published: Aug. 16, 2021

Herein we report the copper-catalyzed silylation of propargylic difluorides to generate axially chiral, tetrasubstituted monofluoroallenes in both good yields (27 examples >80%) and enantioselectivities (82-98% ee). Compared previously reported synthetic routes chiral allenes (ACAs) from prochiral substrates, a mechanistically distinct reaction has been developed: enantiodiscrimination between enantiotopic fluorides set an axial stereocenter. DFT calculations vibrational circular dichroism (VCD) suggest that β-fluoride elimination alkenyl copper intermediate likely proceeds through syn-β-fluoride pathway rather than anti-elimination pathway. The effects C1-symmetric Josiphos-derived ligand on reactivity enantioselectivity were investigated. Not only does this showcase species (like their alkyl counterparts) can undergo elimination, but be achieved enantioselective fashion.

Language: Английский

Highly tunable multi-borylation of gem-difluoroalkenes via copper catalysis DOI
Jiefeng Hu, Yue Zhao, Zhuangzhi Shi

et al.

Nature Catalysis, Journal Year: 2018, Volume and Issue: 1(11), P. 860 - 869

Published: Oct. 26, 2018

Language: Английский

Citations

113
Synthesis of Alkylated Monofluoroalkenes via Fe-Catalyzed Defluorinative Cross-Coupling of Donor Alkenes with gem-Difluoroalkenes DOI
Ling Yang, Weiwei Ji, E. Lin

et al.

Organic Letters, Journal Year: 2018, Volume and Issue: 20(7), P. 1924 - 1927

Published: March 19, 2018

A reductive cross-coupling of gem-difluoroalkenes with diverse unactivated and heteroatom substituted olefins through a Fe-catalyzed hydrogen atom transfer (HAT) strategy is reported. Different from the previous HAT-type olefin reactions, presence fluorine in molecule results stereoselective β-F cleavage, leading to C(sp2)–C(sp3) bond formation. wide variety alkylated monofluoroalkenes were obtained good efficiency excellent Z selectivity under air- water-tolerant reaction conditions. similar defluorinative coupling was also realized.

Language: Английский

Citations

98
Copper-Catalyzed Carbon–Silicon Bond Formation DOI

Jake R. Wilkinson,

Courtney E. Nuyen,

Trent S. Carpenter

et al.

ACS Catalysis, Journal Year: 2019, Volume and Issue: 9(10), P. 8961 - 8979

Published: Aug. 20, 2019

Organosilanes have become a mainstay in organic synthesis as they can participate wide number of reactions where act soft carbon nucleophile. They engage coupling C–C, C–N, C–O, or variety other bonds are formed. Furthermore, organosilanes effective partners C–H activations. Despite their utility, typically relies on precious metals such platinum and palladium. In the past several years, there has been considerable effort to develop new procedures, which rely inexpensive catalysts first-row transition metals. More specifically, copper-catalyzed silylations undergone significant development decade. Copper-catalyzed generally either silylborane, silylzinc, disilane silicon source. However, different transformations be performed with this small set reagents including conjugate addition, addition alkynes, allenes, carbonyls, reactions, substitutions. Nearly all these exhibit high levels diastereoselectivity, regioselectivity, enantioselectivity, depending transformation. Moreover, is still plenty room for further silylations, should provide an alternative more traditional silylations.

Language: Английский

Citations

93
Zinc-Mediated Decarboxylative Alkylation of Gem-difluoroalkenes DOI

Liting Yu,

Mei‐Lin Tang, Chang‐Mei Si

et al.

Organic Letters, Journal Year: 2018, Volume and Issue: 20(15), P. 4579 - 4583

Published: July 19, 2018

An efficient and mild zinc-mediated decarboxylative alkylation of gem-difluoroalkenes with N-hydroxyphthalimide (NHP) esters, to give monofluoroalkenes in moderate excellent yields high Z-selectivity is reported. The reaction tolerates a broad range functional groups can be easily scaled up, which thus may pave the way for its further applications medicinal chemistry materials science.

Language: Английский

Citations

85
Stereoselective Palladium‐Catalyzed C−F Bond Alkynylation of Tetrasubstituted gem‐Difluoroalkenes DOI
Qiao Ma, Yanhui Wang, Gavin Chit Tsui

et al.

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(28), P. 11293 - 11297

Published: April 18, 2020

A stereoselective Pd(PPh3 )4 -catalyzed C-F bond alkynylation of tetrasubstituted gem-difluoroalkenes with terminal alkynes has been developed. This method gives access to a great variety conjugated monofluoroenynes bearing alkene moiety well-defined stereochemistry. Chelation-assisted oxidative addition Pd the is proposed account for high level stereocontrol. An X-ray crystal structure key monofluorovinyl PdII intermediate obtained first time as evidence mechanism.

Language: Английский

Citations

82
Palladium-Catalyzed Stereoselective Defluorination Arylation/Alkenylation/Alkylation of gem-Difluorinated Cyclopropanes DOI
Ebrahim‐Alkhalil M. A. Ahmed, Ayman M. Y. Suliman,

Tian‐Jun Gong

et al.

Organic Letters, Journal Year: 2019, Volume and Issue: 21(14), P. 5645 - 5649

Published: July 9, 2019

A palladium-catalyzed cross-coupling of gem-difluorinated cyclopropanes with boronic acids, providing the corresponding arylated/alkenylated/alkylated 2-fluoroallylic scaffolds, is generated. This new approach has good functional group compatibility for both and acids; thus, an array synthetic building blocks monofluoroalkene scaffolds including conjugated fluorodiene skipped gave yields high Z-selectivity. Moreover, proficient application was described monofluoroalkene, whereas alkyl fluoride constructed through hydrogenation.

Language: Английский

Citations

79
Inorganometallics (Transition Metal–Metalloid Complexes) and Catalysis DOI Creative Commons
Bogdan Marciniec, Cezary Pietraszuk, Piotr Pawluć

et al.

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(3), P. 3996 - 4090

Published: Dec. 30, 2021

While the formation and breaking of transition metal (TM)-carbon bonds plays a pivotal role in catalysis organic compounds, reactivity inorganometallic species, that is, those involving (TM)-metalloid (E) bond, is key importance most conversions metalloid derivatives catalyzed by TM complexes. This Review presents background its development over last 15 years. The results mechanistic studies presented are related to occurrence TM-E TM-H compounds as reactive intermediates catalytic transformations selected metalloids (E = B, Si, Ge, Sn, As, Sb, or Te). illustrates significance inorganometallics following processes: addition metalloid-hydrogen metalloid-metalloid unsaturated compounds; activation functionalization C-H C-X with hydrometalloids bismetalloids; vinylmetalloids, halides, sulfonates; dehydrocoupling hydrometalloids. first on sums up developments methods for synthesis organometalloid their applications advanced part tandem reactions.

Language: Английский

Citations

56
Ni-Catalyzed Radical-Promoted Defluoroalkylborylation of Trifluoromethyl Alkenes To Access gem-Difluorohomoallylic Boronates DOI

Jian Qiu,

Cece Wang,

Zhou Lü

et al.

Organic Letters, Journal Year: 2022, Volume and Issue: 24(12), P. 2446 - 2451

Published: March 21, 2022

gem-Difluoroalkenyl boronates are attractive synthons for constructing diverse gem-difluoroalkenes and organoboron compounds. However, the strategies construction of gem-difluorohomoallyl has scarcely been described. Herein, we develop an efficient protocol gem-difluorohomoallylic through a Ni-catalyzed radical-promoted defluoroalkylborylation α-trifluoromethyl alkenes with α-haloboronates under mild conditions. This reaction features broad substrate scope good functional group tolerance transformations.

Language: Английский

Citations

43
Übergangsmetallvermittelte und ‐katalysierte C‐F‐Bindungsaktivierung durch Fluoreliminierung DOI
Takeshi Fujita, Kohei Fuchibe, Junji Ichikawa

et al.

Angewandte Chemie, Journal Year: 2018, Volume and Issue: 131(2), P. 396 - 408

Published: June 28, 2018

Abstract Die Aktivierung von Kohlenstoff‐Fluor‐Bindungen (C‐F‐Bindungen) ist ein bedeutendes Thema in der organischen Synthesechemie. Metallvermittelte und ‐katalysierte Eliminierungen β‐ oder α‐Fluor finden unter milderen Bedingungen statt als oxidative Additionen an C‐F‐Bindungen. α‐Fluor‐Eliminierung wird ausgehend organometallischen Intermediaten mit Fluorsubstituenten α‐Position zu Metallzentren eingeleitet. Umsetzungen durch solche Eliminierungsprozesse (C‐F‐Bindungsspaltungen), welche typischerweise auf eine Kohlenstoff‐Kohlenstoff‐Bindungsknüpfung (oder Kohlenstoff‐Heteroatom‐Bindungsknüpfung) folgen, wurden den vergangenen fünf Jahren zunehmend zur C‐F‐Bindungsaktivierung entwickelt. In diesem Kurzaufsatz fassen wir die Anwendungen Übergangsmetallvermittelter ‐katalysierter Fluoreliminierung Synthesechemie aus einer historischen Perspektive anhand früher Arbeiten systematischen am Beispiel aktueller Untersuchungen zusammen.

Citations

74
Nickel-Catalyzed Defluorinative Reductive Cross-Coupling Reaction of gem-Difluoroalkenes with Thiosulfonate or Selenium Sulfonate DOI
Jian Li, Weidong Rao, Shun‐Yi Wang

et al.

The Journal of Organic Chemistry, Journal Year: 2019, Volume and Issue: 84(18), P. 11542 - 11552

Published: Aug. 19, 2019

A nickel-catalyzed defluorinative reductive cross-coupling of gem-difluoroalkenes with thiosulfonate or selenosulfonates is described. The reaction involves the formation thiolated selenylated monofluoroolefins via regioselective C–F bond cleavage and C–S C–Se features easily available substrates, mild conditions, high E-selectivity. One derivatives by further cross coupling PhMgBr exhibited an aggregation-induced emission enhancement effect.

Language: Английский

Citations

72