This review discusses the various methods for functionalizing pyridine and quinoline scaffolds, including direct selective metalation (DoM), halogen/metal exchange reactions, Li, Mg, and Zn insertion, and trans-metalation approaches, which are then followed by cross-coupling reactions of the Kumada or Negishi types. Selective deprotonation of aryl or pyridyl/quinolinyl derivatives can be performed

Amino acids are important biomolecules with a broad scope of applications in chemical and biological sciences. Their functions and properties depend on their absolute configuration. Therefore, methods for chiral recognition and separation of amino acids are highly sought after. For the purposes of diagnostic and medicinal applications chiral recognition of amino acids in water is particularly relevant

A diastereoselective and enantioselective formal [4 + 1] ylide annulation of chiral sulfonium salts with various substituted Morita-Baylis-Hillman (MBH) adducts leading to optically active isoxazoline N-oxides with three chiral carbon centers has been explored. The salient features of this methodology include a high diastereo- and enantioselective transformation, easily accessible starting materials

A new group of bases with benzophenoneiminyl (bpi) moiety has been synthesized and characterized in this work. The title compound tris(benzophenoneimino)phosphane (P(bpi)3) 1 was prepared with a convenient one-pot approach: benzophenone imine was deprotonated using MeMgCl and reacted with PBr3 in diglyme. The method could be considered as a method of choice for preparing other (amino)phosphanes in

A mechanochemical desymmetrization of symmetrical bis- and tris-alkynes by a controlled 1,3-dipolar cycloaddition reaction using nitrile oxide dipoles (NOs). This operationally simple protocol allows access to 3,5-isoxazole-alkyne adducts from easily prepared or commercially available symmetrical bis- and tris-alkynes in moderate to excellent yields. In addition, we have highlighted the synthetic utility

A rhodium-catalyzed dearomative 1,4-acyl migratory rearrangement reaction of 2-oxypyridines has been developed for the direct synthesis of 2-alkylated pyridones under mild reaction conditions. Different with the former reports, in this protocol, readily accessible and bench stable vinyl N-nosylhydrazones instead of diazoacetates have been used as carbene precursors. As a result, a range of N-alkylated

A novel oxygen-doped graphitic carbon nitride (OCN) material was designed and synthesized via the hydrothermal-calcination method with melamine and hydroperoxide as starting materials. The OCN material was utilized as a highly efficient solid metal-free photocatalyst for the synthesis of 3-arylquinoxalin-2(1H)-ones via the catalytic decomposition of aryl diazonium salts under blue light irradiation

Modified crown ethers are fundamental building blocks in supramolecular chemistry, with applications in phase transfer catalysis, metal extraction, smart materials, and molecular machines. Here we report on a one-pot highly chemo- and regioselective photocatalytic fluoroalkylation protocol for the mono-functionalization of benzo substituted crown ethers. For this important class of macrocycles, the

For the first time condensations of amines with carbonyl compounds have been performed in supercritical carbon dioxide (sc-CO2). The reactions with aldehydes or active ketones proceed at moderate temperatures (35-55 °C) without use of external catalysts. The process is autocatalytic: it is accelerated by the carbonic acid generated in situ by interaction between the released water and the CO2 medium

Ethylenediamine bridged dibenzoxazine proligands were synthesized by a modified Mannich condensation reaction. The reaction of the proligands with two equivalents of AlMe3 resulted in the formation of dinuclear Al(III) compounds in high yield and purity. When the ligand binds to the Al(III) center, it forms two separate six membered N,O chelates with the two Al atoms that resembles the N-alkylated

The novel synthetic approach was employed to synthesize a series of 1,8-dihydropyrazolo[3,4-b]azepine derivatives from 5-aminopyrazoles in three-step synthesis. The structures of the individual derivatives were unambiguously confirmed by spectral methods, including heteronuclear 1H –13C HMBC spectra and other necessary 2D NMR experiments. The obtained pyrazoloazepines and starting aminopyrazoles were

A straightforward method to access novel families of enantioenriched cis-monofluorinated carbocyclic alcohols has been developed through ATH/DKR in up to 97% yield, up to 99:1 dr and enantioinductions up to 97% ee. Trans-difluorinated indans, tetrahydronaphthalenes, tetrahydroquinolines and chromans have been synthesized as well by deoxofluorination of the corresponding cis-fluoro alcohols. The reaction

A methodology for the formal addition of β-acylalkenyl anions was developed by utilizing the [1,2]-phospha-Brook rearrangement under Brønsted base catalysis. The two-step reaction involves the catalytic addition of α-oxygenated propargyl anions generated via [1,2]-phospha-Brook rearrangement to electron-deficient ketones and subsequent alcoholysis to afford tertiary alcohols having an enone moiety

We report the design of a versatile alkyne-bearing derivative of the donor-acceptor fluorophore 2,4,5,6‑tetrakis(9H-carbazol-9-yl) isophthalonitrile (4CzIPN) suitable for further targeted modifications via copper catalysed Azide Alkyne Cycloaddition (CuAAC). The newly synthesised photoredox catalyst notably exhibits analogously unique photoelectronic and steric features as the well-established carbazolyl

Herein a concise and efficient method for synthesis of aziridines has been developed via a formal intermolecular [2+1] cycloaddition reaction of saccharin-derived cyclic ketimines with sulfur ylides in high yields under mild conditions. This methodology features high atom-economy, broad substrate scope and an operationally simple procedure, affording the aziridines with excellent yields and diastereoselectivity

Dithienopyrazines are only scarcly used as building blocks in organic electronic materials. Here, we report efficient preparation and investigation of syn- and anti-dithienopyrazines, which were functionalized with triaraylamine units to provide different series of donor-acceptor-donor-type materials. The characterization of the optoelectronic properties resulted in valuable structure-property relationships

The nonmammalian 8-carbon saccharide 3-Deoxy-D-manno-oct-2-ulsonic acid (Kdo) is the structural unit of bacterial lipopolysaccharides (LPSs) and capsular polysaccharides. In the inner core region of LPSs, Kdo is present, and this region is structurally conserved. Being nonmammalian in origin, Kdos are effectively recognized by the machinery of the native and adaptive immune system. Therefore, the synthesis

An organocatalytic asymmetric synthesis of directly linked benzothiazole-dihydroimidazoles with two adjacent tertiary-quaternary stereocenters through a Mannich-type reaction of isocyanoacetates with N-(2-benzothiazolyl)imines is disclosed. When employing bifunctional dihydroquinine-derived squaramide as catalyst, moderate to excellent yields (up to 97% yield), moderate diastereoselectivities and excellent

The catalyst-free electrochemical halogenation and trifluoromethylation of 4H-pyrido[1,2-a]pyrimidin-4-ones was realized under external oxidant-free conditions. This strategy provides an easy and green access to functionalized new 4H-pyrido[1,2-a]pyrimidin-4-one derivatives with broad scope, good functional group tolerance and high regioselectivity.

: 2-Cyanobenzaldehye (also called 2-formylbenzonitrile) and related 2-acylbenzonitriles belong to a class of bifunctional aromatic compounds that emerged as useful starting materials in developing efficient cascade-type reactions leading to different heterocyclic compounds. The variety of sometimes unpredictable mechanisms that rise from these structurally simple starting materials renders this class

The geometric and electronic structure of 1,3-dipolar species, in particular of nitrile imines, can be surprisingly intricate. A particular example is the C-phenyl-nitrilimine, which exists as two energy minima that constitute bond-shift isomers. Questioning whether substituents in the phenyl ring could affect the existence of such bond-shift isomers, here we investigate the meta and para OH substituted

Herein, we report a copper-catalyzed intramolecular electrophilic aromatic substitution (SEAr)‒oxidation process to access a wide range of diversified xanthone derivatives using air as a sole oxidant. Specifically, this protocol affords hitherto unknown styryl-/alkenyl-substituted xanthone derivatives in moderate to high yields. The practicality of the method has been demonstrated by gram-scale syntheses