- Syntheses with Nitriles, LXXII. Ricinine - A Simple Synthesis
-
Cyclization of 1,1-dicyano-4-(N,N-dimethylamino)-2-methoxy-1,3-butadiene leads to 4-methoxy-2(1H)-pyridone-3-carbonitrile and 2,4-dimethoxy-pyridine-3-carbonitrile.Methylation of both products yields ricinine. - Keywords: 4-Methoxy-1-methyl-2(1H)-pyridone-3-carbonitrile; Alkaloid synthesis
- Mittelbach, Martin,Kastner, Gabriele,Junek, Hans
-
-
Read Online
- Synthesis and DABCO-induced demethylation of 3-cyano-4-methoxy-2-pyridone derivatives
-
An efficient method for synthesis and demethylation of 3-cyano-4-methoxy-2-pyridone derivatives has been developed. DABCO-induced demethylation can lead to 3-cyano-4-hydroxy-2-pyridones in DMF at 90°C with high yield. The protocol is applicable for the synthesis of 3-cyano-4-hydroxy-2-pyridone derivatives. The method is simple, efficient, and practical.
- Li, Jing,Tan, Hong-Ru,An, Yu-Long,Shao, Zhi-Yu,Zhao, Sheng-Yin
-
p. 486 - 496
(2019/12/24)
-
- A practical procedure for the selective N-alkylation of 4-alkoxy-2-pyridones and its use in a sulfone-mediated synthesis of N-methyl-4-methoxy-2-pyridone
-
It has been found that selective N-alkylation of 4-alkoxy-2-pyridones can be achieved under anhydrous, mild conditions with tetrabutylammonium iodide and potassium tert-butoxide being employed as the catalyst and the base, respectively. The procedure was applied to the preparation of 4-methoxy-1-methyl-2-pyridone, a valuable building block for heterocycle synthesis.
- Conreaux, David,Bossharth, Emmanuel,Monteiro, Nuno,Desbordes, Philippe,Balme, Geneviève
-
p. 7917 - 7920
(2007/10/03)
-
- Ricinine and its transformations
-
Ricinine was isolated from Ricinus communis L. Its derivatives were obtained.
- Yuldashev
-
p. 274 - 275
(2007/10/03)
-
- Lithiation of 4-Methoxy-2-pyridones. Synthetic Entry to Tenellin and Funiculosin, and Related Natural 3,5-Disubstituted 4-Oxy-2-pyridones
-
Lithiation of 4-methoxy-2-pyridone with butyllithium at -78 deg C occurs at the C-3 position exclusively.Subsequent reactions with MeOD, MeI, CO2, benzaldehyde or (E)-but-2-enal then lead to the corresponding C-3-substituted derivatives. in a one-pot procedure, treatment of 1,2-dihydro-4-methoxy-1-methyl-2-oxopyridine-3-carboxylic acid with ammonia in the presence of a polyphosphate buffer at 80 deg C produced natural ricinine in 58percent overall yield.A convenient three-step synthesis of 5-aryl- and 5-alkyl-substituted 4-methoxy-2-pyridones is described.Lithiation of these substrates, followed by reaction with electrophiles, provided a convenient route to 3,5-disubstituted 4-oxy-2-pyridones, and a synthetic entry to natural products, e. g. tenellin and funiculosin, containing this structural feature.
- Buck, Judith,Madeley, J. Paul,Pattenden, Gerald
-
-