Highly Selective Synthesis of 1,3-Enynes, Pyrroles, and Furans by Manganese(I)-Catalyzed C–H Activation

ACS Catalysis, Journal Year: 2019, Volume and Issue: 10(1), P. 197 - 202

Published: Nov. 21, 2019

A highly selective Mn(I)-catalyzed alkenylation of arenes and heteroarenes with 1,3-diynes is described. The reported transformation overcomes regio-, chemo-, stereoselectivity challenges associated the use these coupling partners. Both symmetrical unsymmetrical diynes can be applied in this protocol, affording single isomers not only synthesis 1,3-enynes but also one-step preparation pyrroles furans. This simple strategy features wide functional group tolerance, good reproducibility, preparative scale utility. manganese catalyst plays a crucial role C–H activation enabling high selectivity previously challenging internal alkynes. Furthermore, synthetic value method highlighted by diverse postsynthesis functionalizations final products.

Language: Английский

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Recent Advances in Cyclization Reactions of 1,6‐Enynes

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: 366(6), P. 1220 - 1268

Published: Jan. 22, 2024

Abstract Elaborated molecular architectures, specifically those bearing one or more carbon stereocenters, stand as an important class of carbocyclic and heterocyclic frameworks because they are frequently occurring core structures in numerous natural products biologically active pharmaceutical molecules. Over the past few decades, development versatile synthetic approaches via cascade cyclization reactions 1,6‐enynes for construction a series fused spiro compounds has been focus great deal research initiatives. These synthesis strategies peculiarly fascinating context assembly wide array molecules, products, agrochemicals, functional materials. In this review, recent developments transformations with diverse coupling reagents summarized since 2018, which could be divided into five categories: 1) Introduction; 2) Transition metal catalyzed 1,6‐enynes; 3) Metal‐free 4) Visible‐light‐induced 5) Electrocatalytic 1,6‐enynes.

Language: Английский

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Propargylic Alcohols as Coupling Partners in Transition‐Metal‐Catalyzed Arene C−H Activation

Advanced Synthesis & Catalysis, Journal Year: 2020, Volume and Issue: 362(23), P. 5238 - 5256

Published: Sept. 21, 2020

Abstract Transition‐metal‐catalyzed site selective arene C−H bond activation concomitant functionalization with various coupling partners gain magnificent attraction in synthetic organic chemistry as complementary to traditional transformations. Mechanistically, these approaches involve directing group assisted concerted metalation‐deprotonation (CMD), migratory insertion, and reductive elimination sequences. In this realm, diverse categories of were employed buddies. Particularly alkynes enormous attention annulating agents. These units coordinates metalcycle through π‐interaction produce annulation outcomes a straightforward manner. Very recently, propargylic alcohols appointed valuable archetypes armoury, they have shown regio‐ chemoselective insertion into primary species via hydroxy chelation. The influential regioselectivity was drawn by dual coordination metal complexes the pendent hydroxyl group. review, we focused on annulations arenes alcohols, which afford intricate cycles well complex acyclic motifs trouble‐free We categorized transformations based number atoms involved along some addition reactions. anticipate pave way towards enhanced endeavours for discovering novel reaction avenues. magnified image

Language: Английский

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Copper(I)-catalyzed diastereo- and enantio-selective construction of optically pure exocyclic allenes

Nature Communications, Journal Year: 2020, Volume and Issue: 11(1)

Published: Aug. 27, 2020

Among about 150 identified allenic natural products, the exocyclic allenes constitute a major subclass. Substantial efforts are devoted to construction of axially chiral allenes, however, strategies prepare still rare. Herein, we show an efficient strategy for asymmetric synthesis with simultaneous control axial and central chirality through copper(I)-catalyzed intramolecular reductive coupling 1,3-enynes cyclohexadienones. This tandem reaction exhibits good functional group compatibility corresponding optically pure bearing cis-hydrobenzofuran, cis-hydroindole, cis-hydroindene frameworks, obtained high yields (up 99% yield), excellent diastereoselectivities (generally >20:1 dr) enantioselectivities (mostly >99% ee). Furthermore, gram-scale experiment several synthetic transformations also presented.

Language: Английский

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Recent advances and perspectives in manganese-catalyzed C–H activation

Catalysis Science & Technology, Journal Year: 2020, Volume and Issue: 11(2), P. 444 - 458

Published: Dec. 10, 2020

Manganese-catalyzed C–H activation has become an emerging area in organic chemistry. These efficient and eco-friendly manganese catalysed reactions provides new opportunities the field of synthetic

Language: Английский

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Transition‐Metal Catalyzed Stereoselective Desymmetrization of Prochiral Cyclohexadienones

The Chemical Record, Journal Year: 2021, Volume and Issue: 21(12), P. 3689 - 3726

Published: June 19, 2021

The development of transition-metal catalyzed enantioselective and diastereoselective transformations has contributed many advances in the field synthetic organic chemistry. Particularly, stereoselective desymmetrization prochiral cyclohexadienones represents a powerful strategy for accessing highly functionalized stereochemically enriched scaffolds, which are often found biologically active compounds natural products. In recent years, several research groups including our group have made significant progress on desymmetrizations 2,5-cyclohexadienones. this account, we will provide an overview developments area employing Pd, Cu, Rh, Au, Ag, Ni, Co, Mn-catalysts.

Language: Английский

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Hydrosilylation of Esters Catalyzed by Bisphosphine Manganese(I) Complex: Selective Transformation of Esters to Alcohols

Organic Letters, Journal Year: 2020, Volume and Issue: 22(9), P. 3642 - 3648

Published: April 9, 2020

Selective and efficient hydrosilylations of esters to alcohols by a well-defined manganese(I) complex with commercially available bisphosphine ligand are described. These reactions easy alternatives for stoichiometric hydride reduction or hydrogenation, employing cheap, abundant, nonprecious metal is attractive. The were performed at 100 °C under solvent-free conditions low catalyst loading. A large variety aromatic, aliphatic, cyclic bearing different functional groups selectively converted into the corresponding in good yields.

Language: Английский

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Recent advances on non-precious metal-catalyzed C–H functionalization of N-heteroarenes

Chemical Communications, Journal Year: 2021, Volume and Issue: 58(1), P. 10 - 28

Published: Nov. 18, 2021

N-Heteroarenes are widely used for numerous medicinal applications, lifesaving drugs and show utmost importance as intermediates in chemical synthesis. This feature article highlights the recent advances, from 2015 to August 2021, on sp2 sp3 C-H bond functionalization reactions of various N-heteroarenes catalyzed by non-precious transition metals (Mn, Co, Fe, Ni, etc.). The salient features report are: (i) development newer catalysis Csp2-H activation categorized into alkylation, alkenylation, borylation, cyanation, annulation reactions, (ii) advances Csp3-H considering approaches alkylation well alkenylation processes, (iii) synthetic applications practical utility catalytic protocols utilized late-stage drug development; (iv) scope along with mechanistic studies detail findings important processes.

Language: Английский

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Manganese/NaOPh co-catalyzed C2-selective C–H conjugate addition of indoles to α,β-unsaturated carbonyls

Green Synthesis and Catalysis, Journal Year: 2021, Volume and Issue: 2(1), P. 66 - 69

Published: Jan. 31, 2021

A manganese/NaOPh co-catalyzed C2-selective C–H conjugate addition of indoles to α,β-unsaturated carbonyls has been developed. The reaction features very high atom economy in which no stoichiometric reagents/additives were employed. crucial role sodium phenolate (NaOPh) as a synergetic catalyst was revealed the screening process and mechanistic experiments.

Language: Английский

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Manganese(I)‐Catalyzed Site‐Selective C6‐Alkenylation of 2‐Pyridones Using Alkynes via C−H Activation

Advanced Synthesis & Catalysis, Journal Year: 2021, Volume and Issue: 363(10), P. 2586 - 2593

Published: March 9, 2021

Abstract A Mn(I)‐catalyzed chelation‐assisted direct C6−H alkenylation of 2‐pyridones with both terminal and internal alkynes in a highly regio‐ stereo‐selective manner has been developed. The catalytic system consisting Mn(CO) 5 Br catalyst KOAc additive allows 1‐(2‐pyridyl)‐2‐pyridones to undergo various methyl tert ‐butyl ether (MTBE) furnish the C6‐alkenylated 2‐pyridone products high yields, occurs CH 2 Cl at increased loadings. Mechanistic studies suggest involvement five‐membered organomanganese as key intermediate cycle. magnified image

Language: Английский

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