Synthesis of 5-alkylated barbituric acids and 3-alkylated indoles via microwave-assisted three-component reactions in solvent-free conditions using Hantzsch 1,4-dihydropyridines as reducing agents.
Reaction of barbituric acids with aldehydes and dihydropyridines in one pot under microwave (MW) irradiation in the absence of solvent, affords 55–82% of the 5-benzylated barbituric acids. Use of alkyl nitriles or barbituric acids with indole-3-aldehyde and dihydropyridine (DHP) afforded 3-alkylated indoles in 57–76 % yield. In each case DHPs are converted to pyridines.
Biswajita
B
Baruah
P
P
Seetham Naidu
Pallabi
P
Borah
Pulak J
PJ
Bhuyan
D000478:Alkylation; D001463:Barbiturates / Q000138:chemical synthesis*; D004095:Dihydropyridines / Q000737:chemistry*; D007211:Indoles / Q000138:chemical synthesis*; D008872:Microwaves; D010084:Oxidation-Reduction
D001463:Barbiturates; D004095:Dihydropyridines; D007211:Indoles; C038806:1,4-dihydropyridine; C032232:barbituric acid