DihydropyridinePiperidineAbstractAn unexpected reaction of pyridine with acetyl chloride to give N-acetyl-1,2 and 1,4-dihydropyridyl acetic acid (1, 2) in high yield and regioselectivity has been reported. The key step is the formation of a zwitterionic pyridinium ketene enolate. The effect of ...
Lewis acid-catalyzed Diels–Alder reaction of pyridinecarbaldehydes and Danishefsky’s diene and derivatives provides access to pyridyl-substituted dihydropyranones. The reaction of 2-pyridinecarbaldehyde and Danishefsky’s diene occurs in 65% yield in the presence of 2 mol% of the lanthanide catalyst...
Reaction of DMAP with acetylenedicarboxylic acid leads spontaneously to the bis-adduct in high yields. On reaction with perbenzoic acid the strongly polar N-oxide is formed. Nitration of DMAP with HNO3/H2SO4 gives the 3-nitro derivatives in 81 % yield and, under forcing condition; the 3,5...
SYNTHESIS AND REACTIONS OF SOME NEW THIENO[2,3-b]QUINOXALINES AND THEIR RELATED COMPOUNDS Reaction of 2-chloroquinoxaline-3-carbonitril(1) with different types of nucleophiles such as thiourea, sodium methoxide, aniline, a-mercaptoacetic acid, e... Mahgoub,A S. - 《Phosphorus Sulfur and Silic...
This is most clearly seen in nucleophilic substitution reactions where pyridine is used to activate alcohols, the hydroxyl group is a poor leaving group. It is believed that on the addition of pyridine into the reaction media, the alcohol forms a short-lived complex with it and this facilitates...
After 24h of reflux in the presence of 10mL of acetic acid, the reaction mixture led to a yellow solution, from which a pale-yellow solid was separated by rotatory evaporation. The solid was purified employing column chromatography in analogous conditions to the ones previously mentioned (368mg,...
Facile, Regioselective Syntheses of N-Alkylated 2,3-Diaminopyridines and Imidazo[4,5-b]pyridines The reductive amination of aldehydes with 13 using borane-pyridine in acetic acid affords the N-1 substituted imidazo[4,5-b]pyridines in one step, ......
PreparationThe preparation of 2,6-Pyridinedimethanol is as follows:2640g of 2,6-dibromomethylpyridine, 3L of 30% aqueous sodium hydroxide solution, and 10L of ethanol were placed in a 20L reaction flask. Turn on the agitation. The reaction solution was heated to reflux and the reaction was...
The heteropolyacid catalyst, H5PV2Mo10O40 (0.5 g, 0.2 mmol) was dissolved in a mixture of ethanol (25 mL) and water (5 mL). Pyridine-2-thiol (4 mmol) and 30% H2O2 (13 mmol) were added to the solution. The reaction mixture was stirred at room temperature for 3 h. The solid ob...
The synthesis of pyrrolopyridines 138 and pyrrolopyridinones 140. A series of bis-amides 141 which were synthesized by U-4CR involving N-Boc-pyrrole-2-carbaldehyde, 2-oxo-2-phenylacetic acids, amines, and isocyanides, undergo acid-mediated indole cyclization reaction under MWI at 100°C for ...