Synthesis of triarylpyridines with sulfonate and sulfonamide moieties via a cooperative vinylogous anomeric-based oxidation

Abstract

Herein, novel magnetic nanoparticles with pyridinium bridges namely Fe3O4@SiO2@PCLH-TFA through a multi-step pathway were designed and synthesized. The desired catalyst and its corresponding precursors were characterized with different techniques such as Fourier transform infrared (FT-IR) spectroscopy, 1H NMR, 13C NMR, Mass spectroscopy, energy dispersive X-ray (EDX) analysis, thermogravimetric/derivative thermogravimetry (TG/DTG) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and vibrating sample magnetometer (VSM). In addition, the catalytic application of the prepared catalyst in the synthesis of new series of triarylpyridines bearing sulfonate and sulfonamide moieties via a cooperative vinylogous anomeric-based oxidation was highlighted. The current trend revealed that the mentioned catalyst shows high recoverability in the reported synthesis.

1,2-Silyl Shift-Induced Heterocyclization of Propargyl Silanes: Synthesis of Five-Membered Heterocycles Containing a Functionalized Olefin Side Chain

“…Protonated intermediates of type PhSe­(H)­C + -C­( Si )­(H)-R is better stabilized than Hal­(H)­C + -C­( Si )­(H)-R due to the intrinsic properties of the selenyl substituent; therefore, compounds containing the PhSe moiety are more prone to isomerization. On the other hand, 1,3-allylic strain can preorganize the product conformation so that the vinylogous anomeric effect ( n Se –π CC → σ* C‑heteroatom interaction) can play a role in weakening the C-heteroatom bond in the allylic position and lead to the E / Z -isomerization. A single crystal suitable for X-ray analysis was obtained for product 7i , confirming both the double bond geometry and the structure in addition to the 2D-NOESY spectroscopic studies .…”

“…The reaction was performed following general procedure A: N -(4-( tert -butyldimethylsilyl)­hex-5-yn-1-yl)-4-nitrobenzenesulfonamide ( 6f ; 50 mg, 0.13 mmol, 1.0 equiv) in CHCl 3 (3 mL), NIS (28 mg, 0.13 mmol, 1.0 equiv) was added at 0 °C, reaction temperature 0 °C, reaction time 2.5 h. Column chromatography (eluent: DCM/Hex: 30 → 40%) afforded silyl pyrrolidine 7i (17 mg, 26%) as an amorphous solid. Compound 7i (2 mg) was suspended in DCM (0.6 mL) and EtOH (0.3 mL), heated in an oil bath at 70 °C until dissolution and left to recrystallize to afford monocrystals suitable for X-ray crystallography analysis, mp 160–161 °C (decomposes >165 °C). 1 H NMR (500 MHz, CDCl 3 ): δ 8.40 (d, 2H, J = 8.9), 8.12 (d, 2H, J = 8.9), 6.65 (d, 1H, J = 0.8), 4.25 (dd, 1H, J = 9.5, 7.4), 3.56 (dt, 1H, J = 11.3, 6.7), 3.50 (ddd, 1H, J = 11.3, 8.0, 2.3), 2.02 (ddtd, 1H, J = 14.1, 13.1, 6.7, 2.2), 1.85 (ddq, 1H, J = 13.1, 6.8, 2.3), 1.80–1.65 (m, 1H), 1.36–1.26 (m, 1H), 0.94 (s, 9H), 0.31 (s, 3H), 0.28 (s, 3H).…”

Catalytic Application of a Novel Basic Alkane‐sulfonate Metal‐organic Frameworks in the Preparation of Pyrido[2,3‐d]pyrimidines via a Cooperative Vinylogous Anomeric‐based Oxidation

“…[41] Also, this concept for the reduction of compounds by NADH and NADPH 2 has acted via a hydride transfer. [14][15][16][17][42][43][44][45] The development of cooperative vinylogous anomeric-based oxidation (CVABO) is at the forefront of organic chemistry due to the importance of this concept in promoting the synthesis of organic compounds with biological properties. [38][39][40] Recently, we have reviewed the role of the above-mentioned concepts comprehensively.…”

“…In recent years, the anomeric‐based oxidation (ABO) concept has been known for the final step of the oxidation/reduction mechanism in the preparation of biological compounds such as ( N ‐methyl‐pyrrole)‐pyrazolo[3,4‐ b ]pyridines, pyrimido[4,5‐ b ]quinolones and (3'‐indolyl)‐pyrazolo[3,4‐ b ]pyridin (Scheme 1). [41] Also, this concept for the reduction of compounds by NADH and NADPH 2 has acted via a hydride transfer [14–17,42–45] . The development of cooperative vinylogous anomeric‐based oxidation (CVABO) is at the forefront of organic chemistry due to the importance of this concept in promoting the synthesis of organic compounds with biological properties [38–40] .…”

Acidic tributyl phosphonium-based ionic liquid: an efficient catalyst for preparation of diverse pyridine systems via a cooperative vinylogous anomeric-based oxidation

“…In turn, a cooperative vinylogous anomeric-based oxidation was investigated to justify the mechanism of synthesis of pyridines. 53–56…”