18103-77-0

Upstream product

• 108-89-4 picoline 
• 93-89-0 benzoic acid ethyl ester 
• 611-74-5 N,N-dimethylbenzamide 
• 1620-76-4 2-Cyano-4-methylpyridin 
• 108-86-1 bromobenzene 
• 1003-67-4 4-methylpyridine-1-oxide 
• 10364-94-0 1-benzoylimidazole 
• 501-65-5 diphenyl acetylene 
• 536-74-3 phenylacetylene 

Downstream Products

• 58088-62-3 C-(4-methyl-pyridin-2-yl)-C-phenyl-methylamine 
• 58088-24-7 (4-methyl-pyridin-2-yl)-phenyl-methanone oxime 
• 82226-09-3 (4-methylpyridin-2-yl)-3-phenylmethanol 

Relevant academic research and scientific papers

From Pyridine- N-oxides to 2-Functionalized Pyridines through Pyridyl Phosphonium Salts: An Umpolung Strategy

The reactions of pyridine-N-oxides with Ph3P under the developed conditions provide an unprecedented route to (pyridine-2-yl)phosphonium salts. Upon activation with DABCO, these salts readily serve as functionalized 2-pyridyl nucleophile equivalents. This umpolung strategy allows for the selective C2 functionalization of the pyridine ring with electrophiles, avoiding the generation and use of unstable organometallic reagents. The protocol operates at ambient temperature and tolerates sensitive functional groups, enabling the synthesis of otherwise challenging compounds.

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.

Rhodium-Catalyzed Pyridine N-Oxide Assisted Suzuki-Miyaura Coupling Reaction via C(O)-C Bond Activation

A rhodium-catalyzed Suzuki-Miyaura coupling reaction via C(O)-C bond activation to form 2-benzoylpyridine N-oxide derivatives is reported. Both the C(O)-C(sp2) and C(O)-C(sp3) bond could be activated during the reaction with yields up to 92%. The N-oxide moiety could be employed as a traceless directing group, leading to free pyridine ketones.

Room Temperature Metal-Catalyzed Oxidative Acylation of Electron-Deficient Heteroarenes with Alkynes, Its Mechanism, and Application Studies

Herein, we report an original one-step, simple, room-temperature, regioselective Minisci reaction for the acylation of electron-deficient heteroarenes with alkynes. The method has broad functional group compatibility and gives exclusively monoacylated products in good to excellent yields. The mechanistic pathway was analyzed based on a series of experiments confirming the involvement of a radical pathway. The 18O-labeling experiment suggested that water is a source of oxygen in the acylated product, and head space GC-MS experiment shows the C-C cleavage occurs via release as CO2.

Iridium-Catalyzed Highly Enantioselective Transfer Hydrogenation of Aryl N-Heteroaryl Ketones with N-Oxide as a Removable ortho-Substituent

A highly enantioselective transfer hydrogenation of non-ortho-substituted aryl N-heteroaryl ketones, using readily available chiral diamine-derived iridium complex (S,S)-1f as a catalyst and sodium formate as a hydrogen source in a mixture of H2O/i-PrOH (v/v = 1:1) under ambient conditions, is described. The chiral aryl N-heteroaryl methanols were obtained with up to 98.2% ee by introducing an N-oxide as a removable ortho-substituent. In contrast, no more than 15.1% ee was observed in the absence of an N-oxide moiety. Furthermore, the practical utility of this protocol was also demonstrated by gram-scale asymmetric synthesis of bepotastine besilate in 51% total yield and 99.9% ee.

Side-chain retention during lithiation of 4-picoline and 3,4-lutidine: Easy access to molecular diversity in pyridine series

The first direct ring-selective lithiation of 4-picoline and 3,4-lutidine has been achieved through the use of BuLi/LiDMAE aggregates to prevent the usual side-chain metallation. Several functionalities have been introduced at the C-2, C-6 and C-5 positions by ring-selective sequential lithiation, opening a simple and fast route to polysubstituted pyridine building blocks. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.