78360-98-2

Upstream product

• 87926-15-6 1-(4-(pyridin-2-ylmethyl)phenyl)ethanone 
• 1585-07-5 1-bromo-4-ethylbenzene 
• 941279-81-8 2,4-dimethyl-3-(pyridin-2-ylmethyl)pentan-3-ol 
• 109-06-8 α-picoline 

Downstream Products

• 898779-90-3 (4-ethylphenyl)(pyridin-2-yl) methanone 

Relevant academic research and scientific papers

Metal-Free Halogen(I) Catalysts for the Oxidation of Aryl(heteroaryl)methanes to Ketones or Esters: Selectivity Control by Halogen Bonding

Metal-free halogen(I) catalysts were used for the selective oxidation of aryl(heteroaryl)methanes [C(sp3)?H] to ketones [C(sp2)=O] or esters [C(sp3)?O]. The synthesis of ketones was performed with a catalytic amount of NBS in DMSO solvent. Experimental studies and density functional theory (DFT) calculations supported the formation of halogen bonding (XB) between the heteroarene and N-bromosuccinimide, which enabled imine–enamine tautomerism of the substrates. No additional activator was required for this crucial step. Isotope-labeling and other supporting experiments suggested that a Kornblum-type oxidation with DMSO and aerobic oxygenation with molecular oxygen took place simultaneously. A background XB-assisted electron transfer between the heteroarenes and halogen(I) catalysts was responsible for the formation of heterobenzylic radicals and, thus, the aerobic oxygenation. For selective acyloxylation (ester formation), a catalytic amount of iodine was employed with tert-butyl hydroperoxide in aliphatic carboxylic acid solvent. Several control reactions, spectroscopic studies, and Time-Dependent Density Functional Theory (TD–DFT) calculations established the presence of acetyl hypoiodite as an active halogen(I) species in the acetoxylation process. With the help of a selectivity study, for the first time we report that the strength of the XB interaction and the frontier orbital mixing between the substrates and acyl hypoiodites determined the extent of the background electron-transfer process and, thus, the selectivity of the reaction.

Copper-Catalyzed Base-Controlled Diastereoselective Synthesis of Tetraarylethanes from 2-Benzylpyridines

A highly efficient and base-controlled diastereoselective synthesis of tetraarylethanes through copper-catalyzed dehydrogenative homocoupling of readily available 2-benzylpyridines is reported. Various dl - and meso -tetraarylethanes were diastereoseletively synthesized by this new protocol, where base plays the role of the principle modulator: Grignard reagents selectively provide the C2 isomers, whereas KO t -Bu promotes the formation of the meso -tetraarylethanes. Interestingly, the presence of excess KO t -Bu generates the (E)-tetraarylethenes as the only product.

Efficient Selenium-Catalyzed Selective C(sp3)?H Oxidation of Benzylpyridines with Molecular Oxygen

An efficient selenium-catalyzed direct oxidation of benzylpyridines in aqueous DMSO has been successfully developed by using molecular oxygen as the oxidant. A variety of benzoylpyridines with broad functional group tolerance were obtained in modest to excellent yields and with exclusive chemoselectivity. (Figure presented.).

Synergistic H4NI-AcOH Catalyzed Oxidation of the Csp3-H Bonds of Benzylpyridines with Molecular Oxygen

The oxidation of benzylpyridines forming benzoylpyridines was achieved based on a synergistic H4NI-AcOH catalyst and molecular oxygen in high yield under solvent-free conditions. This is the first nonmetallic catalytic system for this oxidation transformation using molecular oxygen as the oxidant. The catalytic system has a wide scope of substrates and excellent chemoselectivity, and this procedure can also be scaled up. The study of a preliminary reaction mechanism demonstrated that the oxidation of the Csp3-H bonds of benzylpyridines was promoted by the pyridinium salts formed by AcOH and benzylpyridines. The synergistic effect of H4NI-AcOH was also demonstrated by control experiments. (Figure Presented).

RECYCLIZATION OF 2-BENZYLPYRIDINIUM SALTS TO 2-AMINOBIPHENYLS

Under the influence of aqueous solutions of alkylammonium sulfites, substituted 2-benzylpyridinium salts undergo rearrangement to 2-aminobiphenyls.The competitive processes that occur during rearrangement of the 2-benzylpyridinium salts were studied.