Divergent Gold Catalysis: Unlocking Molecular Diversity through Catalyst Control

Chemical Reviews, Journal Year: 2021, Volume and Issue: 121(14), P. 8478 - 8558

Published: Feb. 8, 2021

The catalyst-directed divergent synthesis, commonly termed as "divergent catalysis", has emerged a promising technique it allows chartering of structurally distinct products from common substrates simply by modulating the catalyst system. In this regard, gold complexes powerful catalysts they offer unique reactivity profiles compared to various other transition metal catalysts, primarily due their salient electronic and geometrical features. Owing tunable soft π-acidic nature, not only evolved superior contenders for catalyzing reactions alkynes, alkenes, allenes but also, more intriguingly, have been found provide reaction pathways over π-acid such Ag, Pt, Pd, Rh, Cu, In, Sc, Hg, Zn, etc. recent past witnessed renaissance in examples wherein, choosing or fine-tuning ligands, counteranions oxidation states itself, complete switch was observed. However, reviews documenting are sporadic; result, most reports kind remained scattered literature, thereby hampering further development burgeoning field. By conceptualizing idea "Divergent Gold Catalysis (DGC)", review aims consolidate all unified approach necessary pave way advancement exciting area. Based on factors governing divergence product formation, an explicit classification DGC provided. To gain fundamental understanding observed reactivities selectivities, is accompanied mechanistic insights at appropriate places.

Language: Английский

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Recent advances in transition-metal-catalyzed carbene insertion to C–H bonds

Chemical Society Reviews, Journal Year: 2022, Volume and Issue: 51(7), P. 2759 - 2852

Published: Jan. 1, 2022

C-H functionalization has been emerging as a powerful method to establish carbon-carbon and carbon-heteroatom bonds. Many efforts have devoted transition-metal-catalyzed direct transformations of Metal carbenes generated in situ from transition-metal compounds diazo or its equivalents are usually applied the transient reactive intermediates furnish catalytic cycle for new C-C C-X bond formation. Using this strategy unactivated simple alkanes complex molecules can be further functionalized transformed multi-functionalized compounds. In area, carbene insertion bonds paid continuous attention. Diverse catalyst design strategies, synthetic methods, potential applications developed. This critical review will summarize advance dated up July 2021, by categories aliphatic C(sp3)-H, aryl (aromatic) C(sp2)-H, heteroaryl (heteroaromatic) C(sp2)-H bonds, alkenyl alkynyl C(sp)-H, well asymmetric more coverage given recent work. Due rapid development future directions topic also discussed. give authors an overview chemistry with focus on systems

Language: Английский

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Photoinduced Palladium-Catalyzed 1,2-Difunctionalization of Electron-Rich Olefins via a Reductive Radical-Polar Crossover Reaction

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(9), P. 6445 - 6451

Published: April 25, 2023

Palladium-catalyzed cross-coupling reactions belong to the most important transformations for construction of C–C or C-heteroatom bonds. More recently, photochemical activation palladium complexes emerged as a key strategy leverage catalysis at room temperature beyond scope conventional chemistry. Herein, we report on photoinduced palladium-catalyzed 1,2-difunctionalization reaction electron-rich olefins. Mechanistic experiments and computational studies reveal that this proceeds via addition an alkyl radical, followed by oxidation radical intermediate access carbocation intermediates, which are inaccessible classic thermal conditions. The can then be applied variety secondary C–N bond-forming reactions. This now allows general approach toward densely functionalized unsymmetric 1,1-bis(heterocyclyl)alkanes.

Language: Английский

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Advances in gold catalyzed synthesis of quinoid heteroaryls

RSC Advances, Journal Year: 2024, Volume and Issue: 14(29), P. 21047 - 21064

Published: Jan. 1, 2024

Synthesis of quinoid heteroaryls via gold-catalyzed cascade protocols: recent advances and methodologies.

Language: Английский

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Photoinduced Palladium‐Catalyzed Dicarbofunctionalization of Terminal Alkynes

Chemistry - A European Journal, Journal Year: 2021, Volume and Issue: 27(11), P. 3694 - 3699

Published: Jan. 15, 2021

Herein, a conceptually distinct approach was developed that allowed for the dicarbofunctionalization of alkynes at room temperature using simple, bench-stable alkyl iodides and second molecule alkyne as coupling partner. Specifically, photochemical activation palladium complexes enabled this strategic via addition radicals from secondary tertiary formation an intermediate vinyl complex could undergo subsequent Sonogashira reaction with molecule. This alkylation-alkynylation sequence one-step synthesis 1,3-enynes including heteroarenes biologically active compounds high efficiency without exogenous photosensitizers or oxidants now opens up pathways towards cascade reactions catalysis.

Language: Английский

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Metal Bound or Free Ylides as Reaction Intermediates in Metal-Catalyzed [2,3]-Sigmatropic Rearrangements? It Depends

ACS Catalysis, Journal Year: 2021, Volume and Issue: 11(2), P. 829 - 839

Published: Jan. 4, 2021

Density functional theory calculations were applied to study four previously published metal-catalyzed [2,3]-rearrangements from onium ylide intermediates, in pursuit of generalizations about when, during these types reactions, catalysts dissociate. Our results corroborate past studies where free-ylide mechanisms proposed be operative. Results on case indicate that the origin metal–catalyst dissociation can attributed primarily steric bulkiness groups adjacent carbene carbon.

Language: Английский

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Enantioselective para‐C(sp²)−H Functionalization of Alkyl Benzene Derivatives via Cooperative Catalysis of Gold/Chiral Brønsted Acid**

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(40)

Published: Aug. 4, 2022

Abstract An asymmetric para‐ C(sp 2 )−H bond functionalization of alkyl benzene derivatives was successfully developed via cooperative catalysis gold and chiral phosphoric acid (CPA), leading to synthetically useful 1,1‐diaryl motifs. Chiral acid, ligand, molecular sieves were found be crucial for enantioselectivity control this transformation. The salient features protocol include mild conditions, high efficiency, commercially available starting materials, highly chemo‐ site‐ as well enantioselective aromatic C−H functionalization, broad substrate scope, extensive applications the products. mechanistic studies suggested that two CPAs might involved in induction.

Language: Английский

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Catalytic Stereoselective 1,2-cis-Furanosylations Enabled by Enynal-Derived Copper Carbenes

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(2), P. 1037 - 1049

Published: Jan. 8, 2024

1,2-cis-Furanosides are present in various biomedically relevant glycosides, and their stereoselective synthesis remains a significant challenge. In this vein, we have developed approach to 1,2-cis-furanosylations using earth-abundant copper catalysis. This protocol proceeds under mild conditions at room temperature employs readily accessible benchtop stable enynal-derived furanose donors. chemistry accommodates variety of alcohols, including primary, secondary, tertiary, as well mannosyl alcohol acceptors, which been incompatible with most known methods furanosylation. The resulting 1,2-cis-furanoside products exhibit high yields anomeric selectivity both the ribose arabinose series. Furthermore, is independent C2 oxygen-protecting group configuration starting donor. Experimental evidence computational studies support our hypothesis that chelation between oxygen donor an incoming nucleophile responsible for observed 1,2-cis-stereoselectivity.

Language: Английский

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Borane-Catalyzed Carbazolation Reactions of Aryldiazoacetates

Organic Letters, Journal Year: 2021, Volume and Issue: 23(15), P. 5831 - 5835

Published: July 19, 2021

Herein, we report on the tris(pentafluorophenyl)borane-catalyzed reaction of carbazole heterocycles with aryldiazoacetates. We could demonstrate that selective N–H functionalization occurs in case an unprotected carbazole, other N-heterocycles, and secondary amines good yields. In contract, protected undergoes C–H at C-3 position a yield. The application both approaches was studied 41 examples up to 97%

Language: Английский

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Rhodium(II)-Catalyzed Regioselective Remote C–H Alkylation of Protic Indoles

ACS Catalysis, Journal Year: 2021, Volume and Issue: 11(9), P. 4929 - 4935

Published: April 8, 2021

Control of regioselectivity that defies the intrinsic reactivity arene C–H bonds remains a formidable challenge. In this work, dimeric Rh(II) complexes have been applied as an efficient catalyst for regioselective coupling NH indoles with diazo compounds. Two-substituted mostly reacted C(6) selectivity. Mechanistic studies revealed results from hydrogen-bonding directing effect, and C–C bond formation proceeds via Friedel–Crafts-type attack indole toward carbene species. contrast, reaction 4-methoxyindoles occurred exclusively complementary C(7)

Language: Английский

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