Zn(II)-Catalyzed Multicomponent Sustainable Synthesis of Pyridines in Air

The Journal of Organic Chemistry, Год журнала: 2023, Номер 88(6), С. 3650 - 3665

Опубликована: Фев. 28, 2023

Herein, we report a Zn(II)-catalyzed solvent-free sustainable synthesis of tri- and tetra-substituted pyridines using alcohols as the primary feedstock NH4OAc nitrogen source. Using well-defined air-stable Zn(II)-catalyst, 1a, featuring redox-active tridentate azo-aromatic pincer, 2-((4-chlorophenyl)diazenyl)-1,10-phenanthroline (La), wide variety unsymmetrical 2,4,6-substituted were prepared by three-component coupling secondary with NH4OAc. Catalyst 1a is equally compatible four-component coupling. Unsymmetrical also via alcohol two different A series up to 67% yield 1-phenylpropan-1-one or 1,2-diphenylethan-1-one The 1a-catalyzed reactions proceeded efficiently upon replacing corresponding ketones, producing desired in higher yields shorter reaction time. few control experiments performed unveil mechanistic aspects, which indicates that active participation aryl-azo ligand during catalysis enables Zn(II)-complex act an efficient catalyst for present multicomponent reactions. Aerial oxygen acts oxidant dehydrogenation alcohols, H2O H2O2 byproducts.

Язык: Английский

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Modular synthesis of unsymmetric 2,4-diaryl-substituted pyridines through a four-component cyclization strategy under metal-free conditions

Organic Chemistry Frontiers, Год журнала: 2023, Номер 10(19), С. 4794 - 4799

Опубликована: Янв. 1, 2023

We have reported a multicomponent protocol for the synthesis of polysubstituted pyridines through [2 + 2 1 1] condensation sequence under metal-free conditions.

Язык: Английский

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Primary amine C–N bond cleavage for the synthesis of multi-substituted pyridine and pyrrole derivatives

Organic Chemistry Frontiers, Год журнала: 2022, Номер 10(3), С. 780 - 785

Опубликована: Дек. 9, 2022

Synthesis of multi-substituted pyridines and pyrroles was established involved C-N bond cleavage new C–N C–C formation. The adjacent to the primary carbon 1,2-diamino-2-methylpropane selectively cleaved.

Язык: Английский

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Recent Advances in Synthesis of Multiply Arylated/Alkylated Pyridines

The Chemical Record, Год журнала: 2022, Номер 22(9)

Опубликована: Июнь 14, 2022

Abstract Multiply aryl/alkyl‐substituted pyridines are some of the untapped synthetic targets because challenge in regioselectively introducing less polar aryl/alkyl groups at desired positions pyridine framework. Interestingly, importance this family compounds has increased annually, particularly biological and materials engineering applications. The syntheses such have been extensively reported, but there is a lack comprehensive review articles. Hence, discusses recent advances by grouping reaction patterns that generally deliver tri‐, tetra‐, penta‐aryl/alkyl pyridines.

Язык: Английский

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Recent Advances in Synthetic Routes to Azacycles

Molecules, Год журнала: 2023, Номер 28(6), С. 2737 - 2737

Опубликована: Март 17, 2023

A heterocycle is an important structural scaffold of many organic compounds found in pharmaceuticals, materials, agrochemicals, and biological processes. Azacycles are one the most common motifs a have variety applications, including pharmaceuticals. Therefore, azacycles received significant attention from scientists methods synthesizing been developed because their efficient synthesis plays vital role production useful compounds. In this review, we summarize recent approaches to preparing via different as well describe plausible reaction mechanisms.

Язык: Английский

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TMSOTf-mediated Kröhnke pyridine synthesis using HMDS as the nitrogen source under microwave irradiation

RSC Advances, Год журнала: 2022, Номер 12(13), С. 8263 - 8273

Опубликована: Янв. 1, 2022

An efficient protocol for the preparation of pyridine skeletons has been successfully developed involving TMSOTf/HMDS (trifluoromethanesulfonic acid/hexamethyldisilane) system intermolecular cyclization chalcones under MW (microwave) irradiation conditions. This method provides a facile approach to synthesize 2,4,6-triaryl or 3-benzyl-2,4,6-triarylpyridines in good excellent yields. Interestingly, 2,6-diazabicyclo[2.2.2]oct-2-ene core was obtained by changing acid additive Sn(OTf)2, and desired product also confirmed using X-ray single-crystal diffraction analysis.

Язык: Английский

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TBAI/TBHP Catalyzed Synthesis of 2,4,6‐Trisubstituted Pyridines from Oxime Acetates Using Benzylamine as an Effective ArCO Surrogate under Transition Metal‐Free Conditions

ChemistrySelect, Год журнала: 2024, Номер 9(12)

Опубликована: Март 25, 2024

Abstract An efficient TBHP/TBAI mediated strategy has been developed for the synthesis of 2,4,6‐trisubstitued pyridines from ketoxime acetates and benzylamines under metal‐free conditions first time. In this protocol benzylamine acts as an effective ArCO surrogate. This methodology features use inexpensive catalysts, avert additional ligands additives high functional group tolerance. Moreover, 5‐Lipoxygenase enzyme inhibitory activities were performed all synthesised compounds. Among 2,4,6‐trisubstituted 3fg, 3fa 3eg showed good activity.

Язык: Английский

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Regioselective Hydrodeoxygenation of α-Diketones with Phosphites under Visible-Light Catalysis

Organic Letters, Год журнала: 2023, Номер 25(40), С. 7422 - 7427

Опубликована: Окт. 2, 2023

Novel regioselective hydrodeoxygenation of α-diketones with phosphites as the deoxygenation reagent was realized via visible-light photoredox catalysis. Broad substrate scope and high functional group compatibility were obtained. Unsymmetric selectively reduced at carbonyls higher electrophilicity. This unique regioselectivity compared available methods makes it a practical complementary approach for monohydrodeoxygenation α-diketones.

Язык: Английский

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An electrochemical multicomponent cascade annulation and functionalization reaction to enable C(sp³)–H trifluoromethylation

Organic Chemistry Frontiers, Год журнала: 2023, Номер 11(6), С. 1662 - 1667

Опубликована: Дек. 22, 2023

Herein, we describe a novel electrochemistry facilitated one-pot multicomponent cascade annulation and bi-functionalization reaction that enables the efficient synthesis of highly functionalized 3,4-dihydroquinazolinones, realising indirect C(sp 3 )–H trifluoromethylation aromatic ketones.

Язык: Английский

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Multicomponent Synthesis of Heterocycles

Heterocycles, Год журнала: 2022, Номер unknown, С. 215 - 275

Опубликована: Июнь 17, 2022

Язык: Английский

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