1779-91-5

Upstream product

• 101-82-6 2-Benzylpyridine 
• 93-89-0 benzoic acid ethyl ester 
• 694-59-7 pyridine N-oxide 
• 501-65-5 diphenyl acetylene 
• 42353-58-2 1-(1,2-diphenyl-vinyl)-pyrrolidine 
• 107264-09-5 1-fluoro-pyridinium tetrafluoroborate 
• 100-47-0 benzonitrile 

Relevant academic research and scientific papers

Solvatochromism, acidochromism and aggregation-induced emission of propeller-shaped spiroborates

Propeller-shaped pyridyl-enolato-catecholate/-salicyl spiroborates (Sborepy1-6) were synthesized. The complexes Sborepy3-6 show weak emission in fluid solution and aggregation-induced emission enhancement in the aggregation state with large Stokes shifts of 4025-5237 cm?1. Moreover, intense solid-state emissions with high Φf ranging from 25% to 37% were observed for Sborepy3-6 owing to the weak intermolecular interactions in their solid-state. The AIE and intense solid-state emission have been revealed via the X-ray diffraction analysis and theoretical calculations. Furthermore, the solvatochromism in the solution state and the potential application as a fluorescent acidic vapour sensor in the solid state of Sborepy3 and Sborepy6 were also demonstrated.

Photoinduced Divergent Alkylation/Acylation of Pyridine N-Oxides with Alkynes under Anaerobic and Aerobic Conditions

Ortho-alkylated and ortho-acylated pyridines have been conveniently synthesized from pyridine N-oxides and alkynes under visible-light-mediation in a metal-free manner. The alkynes served as both alkylating and acylating agents via switching between anaerobic and aerobic conditions. The overall strategy accommodates a broad scope of substituted pyridine N-oxides and alkynes, with excellent regioselectivity in a number of cases.

ortho-Alkylation of Pyridine N-Oxides with Alkynes by Photocatalysis: Pyridine N-Oxide as a Redox Auxiliary

A photocatalyzed ortho-alkylation of pyridine N-oxide with ynamides and arylacetylenes has been developed, which yields a series of α-(2-pyridinyl) benzyl amides/ketones. Mechanistic studies, including electrochemical studies, radical-trapping experiments, and Stern–Volmer fluorescence quenching studies demonstrate that pyridine N-oxide serves as both a redox auxiliary and radical acceptor to achieve the mild photocatalytic single-electron oxidation of carbon–carbon triple bonds with the generation of a cationic vinyl radical intermediate.

Kinetics of Electrophilic Fluorinations of Enamines and Carbanions: Comparison of the Fluorinating Power of N-F Reagents

Kinetics of the reactions of enamines and carbanions with commonly used fluorinating reagents, N-fluorobenzenesulfonimide (NFSI), N-fluoropyridinium salts, Selectfluor, and an N-fluorinated cinchona alkaloid, have been investigated in acetonitrile. The reactions follow second-order kinetics, and from the measured rate constants one can derive that the fluorinations proceed via direct attack of the nucleophiles at fluorine, not by SET processes. Correlations of the fluorination rates with the pKaH values of the nucleofugal leaving groups and the calculated fluorine plus detachment energies are discussed. The rate constants for the reactions with deoxybenzoin-derived enamines follow the linear free energy relationship log k2(20 °C) = sN(N + E) which allows the empirical electrophilicity parameters E for these fluorinating agents to be derived from the measured rate constants and the tabulated N and sN parameters for the nucleophiles. Though the deviations of the measured rate constants from those calculated by this relationship are larger than for reactions of Csp2-centered electrophiles with nucleophiles, it is shown that the electrophilicity parameters E reported in this work are able to rationalize known fluorination reactions and are, therefore, recommended as guide for designing new electrophilic fluorinations.

Reactivity of 2-benzylpyridyl lithium toward benzonitrile derivatives: Addition versus elimination

This work investigated the reactivity of 2-benzylpyridyl lithium (2-Pyr)C(Ph)(R)Li (R = SiMe3, Li1; R = H, Li2) toward benzonitrile derivatives. Based on the different products, the reaction between lithium salts and nitriles might involve in addition, elimination and bimolecular coupling pathways, respectively. Treatment of Li1 with ArCN (Ar = Ph, p-Tolyl, o-Tolyl, p-OMePh) yielded an addition intermediate pyridyl-1-aza-allyl-lithium [{(2-Pyr)C(Ph)C(Ar)N(SiMe3)}Li]2 (1, Ar = Ph) and its corresponding hydrolysis product 2-benzylpyridyl-ketone 2–5, respectively, in which the reaction involved in a 1,3-shift of -SiMe3 group to form a dimeric pyridyl-1-aza-allyl-lithium then followed by acidic hydrolysis. The MeOLi elimination reaction between Li2 and p-MeO(C6H4)CN resulted in formation of 4-(2-benzylpyridyl)benzonitrile 6. The reaction of Li2 with p-Me(C6H4)CN in the presence of TMEDA generated a 1:2 hydrolysis adduct 2-benzylpyridyl-enaminone 7, however, in the absence of TMEDA it afforded a coupling product of bimolecular nitriles, 1-(4-methylphenyl)-2-cyanophenyl-ethanone 8. We speculated the reaction mechanisms in sequence. The crystal structures of 1 and 5–8 were analyzed.

Aggregation-induced emission (AIE) of pyridyl-enamido-based organoboron luminophores

A new family of pyridyl-enamido-based organoboron complexes (Borepy1-4) with aggregation-induced emission (AIE) properties were developed. They show very weak fluorescence in low-viscosity organic solvents and exhibit intense fluorescence in high-viscosity solvents or in their aggregate/solid states. X-ray crystallographic analysis shows that the weak intermolecular interactions by fixing the molecular conformations of Borepy1-4 are responsible for intense fluorescence in the solid state. TD-DFT calculations show that the maximum absorption bands for Borepy1-4 can be easily tuned.

α-(2-Pyridine)benzyl aryl ketones as potential hypocholesteremic agents

A series of α-(2-pyridine)benzyl aryl ketones were prepared as potential hypocholesteremic agents. The synthesis of these compounds was by conversion of 2-benzylpyridine to its anion with n-butyllithium and condensation of the anion with selected aromatic esters. The ketones were tested for their hypocholesteremic activity in rats, and those compounds showing activity were further tested for estrogenicity. Only those aryl ketones with substituents in the ortho position showed a statistically significant reduction in serum cholesterol. Of these compounds the tert-butyl derivative had the most favorable hypocholesteremic to estrogenic ratio.