Ligand‐Controlled Stereoselective Synthesis of 2‐Deoxy‐β‐C‐glycosides by Cobalt Catalysis

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(22)

Published: March 17, 2023

2-Deoxy-β-C-glycosides represent an important class of carbohydrates that are present in many bioactive molecules. However, owing to the lack substituents at C2 position, stereoselective synthesis 2-deoxy-β-C-glycosides is highly challenging. Herein, we report a ligand-controlled C-alkyl glycosylation reaction access 2-deoxy-β-C-alkyl glycosides from readily available glycals and alkyl halides. This method exhibits broad substrate scope excellent diastereoselectivity under very mild conditions. In addition, unprecedented stereodivergent 2-deoxy-C-ribofuranosides achieved using different chiral bisoxazoline ligands. Mechanistic studies suggest hydrometallation glycal with bisoxazoline-ligated Co-H species may be turnover-limiting stereodetermining step this transformation.

Language: Английский

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Recent Advances in First-Row Transition Metal-Catalyzed Reductive Coupling Reactions for π-Bond Functionalization and C-Glycosylation

Accounts of Chemical Research, Journal Year: 2023, Volume and Issue: 56(22), P. 3292 - 3312

Published: Nov. 2, 2023

ConspectusEfficient construction of ubiquitous carbon-carbon bonds between two electrophiles has garnered interest in recent decades, particularly if it is mediated by nonprecious, first-row transition metals. Reductive coupling advantages over traditional cross-coupling obviating the need for stoichiometric air- and moisture-sensitive organometallic reagents. By harnessing metal-catalyzed reductive as a powerful tool, intricate molecular architectures can be readily assembled through installation C-C across π systems (alkenes/alkynes) via reaction with appropriate electrophiles. Despite advances alkene difunctionalization, there remains significant potential discovery novel pathways. In this regard, development protocols that enable union challenging alkyl/alkynyl high regio- chemoselectivity highly sought-after goal.Apart from π-bond functionalization, found application carbohydrate chemistry, synthesis valuable C-glycosyl compounds. vein, suitable glycosyl donors used to generate reactive radical intermediates under conditions. Through elaborately designed reactions, these trapped furnish pharmaceutically relevant glycoconjugates. Consequently, diversification compound using metal catalysis holds strong appeal.In Account, we summarize our efforts reactions applications alkene/alkyne functionalization C-glycosylation. We will first discuss nickel (Ni)-catalyzed difunctionalization alkenes, aided an 8-aminoquinoline (AQ) directing auxiliary. Next, highlight Ni-catalyzed hydroalkylation alkenyl amides tethered similar AQ-derived Lastly, efficient 1,3-enynes involving site- stereoselective terminal alkynes alkynyl halides NHPI esters.Beyond dicarbofunctionalization, extended paradigm toward C-glycosidic linkages carbohydrates. employing earth-abundant iron (Fe)-based catalyst, show useful radicals generated chlorides These captured bond formation C-aryl, C-alkenyl, C-alkynyl compounds diastereoselectivity. Our multicomponent chlorides, aryl/alkyl iodides, isobutyl chloroformate conditions led C-acyl glycosides. addition Fe Ni, discovered Ti-catalyzed/Mn-promoted synthetic route access C-alkyl C-alkenyl compounds, electron-deficient alkenes/alkynes. further developed electron donor-acceptor (EDA) photoactivation system leveraging decarboxylative deaminative strategies C-glycosylation Ni catalysis. This approach been demonstrated selectively activate carboxyl amino motifs glycopeptide conjugates. Finally, distinct catalytic transformations bench-stable heteroaryl sulfones, achieved stereodivergent both α- β-anomers C-aryl glycosides, one which involves aryl iodides.The findings presented Account are anticipated have far-reaching implications beyond research. foresee results pave way new founded on concept coupling, leading future.

Language: Английский

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Cobalt(II)‐Catalyzed C(sp³)−C(sp³) Coupling for the Direct Stereoselective Synthesis of 2‐Deoxy‐C‐Glycosides from Glycals

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(22)

Published: March 17, 2023

We report a ligand-controlled CoII -catalyzed C(sp3 )-C(sp3 ) coupling hydroalkylation for direct and β-selective synthesis of 2-deoxy-C-glycosides from glycals. This reaction proceeds by radical pathway alkyl halide activation is through ligand control. approach may inspire the development further stereoselective reactions with potential application in field carbohydrates.

Language: Английский

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Recent advances on synthesis of C-glycosides

Carbohydrate Research, Journal Year: 2023, Volume and Issue: 530, P. 108856 - 108856

Published: June 5, 2023

Language: Английский

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Photoredox-catalyzed protecting-group-free C-glycosylation with glycosyl sulfinate via the Giese reaction

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(55), P. 8564 - 8567

Published: Jan. 1, 2023

C-Glycoside analogs of naturally occurring glycoconjugates are useful tools for chemical biology studies, but their synthesis usually requires protection the hydroxyl groups glycosyl donors. Here we report protecting-group-free and photoredox-catalyzed C-glycosylation with sulfinates Michael acceptors via Giese radical addition.

Language: Английский

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