DBU‐catalyzed three‐component one‐pot synthesis of highly functionalized pyridines in aqueous ethanol

Abstract

in Wiley InterScience (www.interscience.wiley.com).1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU) efficiently catalyzes three-component one-pot condensations of aldehyde, malononitrile, and thiophenol to produce highly functionalized pyridines in excellent yield in aqueous ethanol.

Piperidine derivative covalently anchored on uniform spherical mesoporous silica nanoparticle with narrow slit like pores for the synthesis of 2-amino-3, 5-dicarbonitrile-6-arylthio-pyridines

“…The reported Lewis/Brønsted base catalysts include DBU, Et 3 N, piperidine, KF/alumina, K 2 CO 3 /KMnO 4 , etc. [39][40][41][42][43][44][45][46]. Besides these, a few improved methods are reported using various catalysts such as basic ionic liquid [bmIm]OH, ZnCl 2 , silica nanoparticle, boric acid, ZrOCl 2 .8H 2 O/NaNH 2 in [bmim]BF 4 under ultrasound irradiation, nanocrystalline MgO and very recently by Zn(II) and Cd(II) MOFs etc.…”

Synthesis and in vitro antimicrobial evaluation of penta-substituted pyridine derivatives bearing the quinoline nucleus

“…Various methods for the synthesis of penta-substituted pyridines from aromatic and heterocyclic aldehydes involving different catalysts (Evdokimov et al, 2006;Heravi et al, 2010;Lakshmikantam et al, 2010;Singh and Singh, 2009;Mamgain et al, 2009;Sridhar et al, 2009;Banerjee and Sereda, 2009;Ranu et al, 2007) are available but not a single report has been found where 2-chloro-3-formyl quinoline is used for the synthesis of penta-substituted pyridines using piperidine as basic catalyst. Also, the most suitable protocol for the synthesis of functionalized organic compounds would be a one-pot reaction due to the fact that the synthesis can be performed without the isolation of the intermediates, without discharging any functional groups and within short reaction time (Boulard et al, 2004).…”

Synthesis of novel 4-acyl-2-amino-6-sulfanylpyridine-3,5-dicarbonitriles

“…13 Traditionally, compounds 1 are prepared via the threecomponent condensation of an aldehyde, malononitrile, and a thiol. 14 A large number of publications have been devoted to the synthesis of 2-amino-3,5-dicarbonitrile-6-sulfanylpyridines under different conditions using various catalysts such as bases, 3,14 ionic liquid medium, [15][16][17] Lewis acids 18 and boric acid. 19 Herein, we describe the synthesis of novel 2-amino-3,5-dicarbonitrile-6-sulfanylpyridines 4, containing an aroyl or pivaloyl substituent at the 4-position of the pyridine ring.…”