Magnesium Nitride as a Convenient Source of Ammonia: Preparation of Dihydropyridines
作者:Katy L. Bridgwood、Gemma E. Veitch、Steven V. Ley
DOI:10.1021/ol801399w
日期:2008.8.21
Magnesiumnitride (Mg 3N 2) has been investigated for the preparation of dihydropyridines. This is a commercially available, bench-stable solid that generates ammonia upon treatment with protic solvents. The main features of the process are the facile reaction setup and good yields obtained in the majority of cases.
sugar mixtures (LMMs) were synthesized and used for preparation of 1,4-dihydropyridines with aldehydes, 1,3-dicarbonylcompounds, and a nitrogen source as starting materials. Good yields, low reaction times, recyclability of LMMs, and catalyst-free methodology are some of the highlights of this new protocol. GRAPHICAL ABSTRACT
One-Pot Three-Component Synthesis of<i>Hantzsch</i>1,4-Dihydropyridines Promoted by Dimethyl Phosphate Ionic Liquids
作者:Elina Priede、Andris Zicmanis
DOI:10.1002/hlca.201500009
日期:2015.8
one‐pot three‐component reaction of ethyl acetoacetate, AcONH4, and different aldehydes has been successfully performed in the presence of ionic liquids (ILs) possessing a (MeO)2PO counterion. The impact of electronic and steric effects of the substituents of aromaticaldehydes, as well as the influence of different anions of ILs on the product yield, have been investigated. The application of dimethyl
Synthesis of 3,4-dihydropyrimidin-2(1H)-ones and 1,4-dihydropyridines using ammonium carbonate in water
作者:Fatemeh Tamaddon、Zahra Razmi、Abbas Ali Jafari
DOI:10.1016/j.tetlet.2009.12.098
日期:2010.2
known and new3,4-dihydropyrimidin-2(1H)-ones and 1,4-dihydropyridines are prepared efficiently via Biginelli and Hantzsch reactionsusing ammonium carbonate in water. Competition between Biginelli and Hantzsch reactions is observed with pyridine carbaldehydes. Using this methodology, Hantzsch esters are synthesized in higher yields and purities than with other procedures without the use of a catalyst
Covalently Anchored Sulfonic Acid on Silica Gel as an Efficient and Reusable Heterogeneous Catalyst for the One-Pot Synthesis of Hantzsch 1,4-Dihydropyridines under Solvent-Free Conditions
A highly efficientone-potsynthesis of Hantzsch 1,4-dihydropyridines under solvent-free conditions catalyzed by sulfonicacid covalently anchored onto the surface of silica gel is reported here. All types of aldehydes, including aromatic, unsaturated, and heterocyclic aldehydes, gave excellent yields. The silica gel/sulfonicacidcatalyst (SiO 2 -SO 3 H) is completely heterogeneous and can be recycled