Catalyzed reaction of enaminonitrile with primary amines by SbF3: synthesis of new 2-aminosubstituted-pyridine-fused δ-lactones

Abstract

A novel methodology for the synthesis of substituted 2-aminopyridine δ-lactones is reported. It involves the reactions of enaminonitrile, 4,6,6-trimethyl-2-oxo-5,6-dihydro-2H-pyran-3-carbonitrile, with amines which is catalyzed by antimony trifluoride SbF3. The structures of the new compounds obtained were characterized by various spectroscopic methods (IR, 1 H NMR, 13 C NMR and MS).

Synthesis of 2-aminopyridine Lactones and Studies of Their Antioxidant, Antibacterial and Antifungal Properties

“…Substituted 2-aminopyridine δ-lactone derivatives were achieved. 4,6,6-trimethyl-2oxo-5,6-dihydro-2H-pyran-3-carbonitrile (1) was synthesised from 4-hydroxy-4-methylpen tan-2-one [1] (Figure 1), followed by its transformation in enaminonitrile with DMFDMA [1].…”

“…Substituted 2-aminopyridine δ-lactone derivatives were achieved. 4,6,6-trimethyl-2oxo-5,6-dihydro-2H-pyran-3-carbonitrile (1) was synthesised from 4-hydroxy-4methylpentan-2-one [1] (Figure 1), followed by its transformation in enaminonitrile with DMFDMA [1]. The compound 3 was prepared by the reaction of δ-lactone nitrile «4,6,6-trimethyl-2oxo-5,6-dihydro-2H-pyran-3-carbonitrile » 1 with dimethylformamide dimethylacetal DMFDMA in stoichiometric amounts.…”

“…The compound 3 was prepared by the reaction of δ-lactone nitrile «4,6,6-trimethyl-2oxo-5,6-dihydro-2H-pyran-3-carbonitrile » 1 with dimethylformamide dimethylacetal DMFDMA in stoichiometric amounts. The reaction was performed at room temperature during 24 h and afforded good overall yield (72%) [1] according the Figure 2. The compound 3 was prepared by the reaction of δ-lactone nitrile «4,6,6-trimethyl-2-oxo-5,6-dihydro-2H-pyran-3-carbonitrile » 1 with dimethylformamide dimethylacetal DMFDMA in stoichiometric amounts.…”

“…The compound 3 was prepared by the reaction of δ-lactone nitrile «4,6,6-trimethyl-2-oxo-5,6-dihydro-2H-pyran-3-carbonitrile » 1 with dimethylformamide dimethylacetal DMFDMA in stoichiometric amounts. The reaction was performed at room temperature during 24 h and afforded good overall yield (72%) [1] according the Figure 2.…”

“…The reaction of enaminolactone nitrile 3 and primary amines 4a-f in refluxed DMF according to our previous work [1] results in new substituted 2-aminopyridines 5a-f, according Figure 3, results are reported in Table 1. The reaction of enaminolactone nitrile 3 and primary amines 4a-f in refluxed DMF according to our previous work [1] results in new substituted 2-aminopyridines 5a-f, according Figure 3, results are reported in Table 1. The reaction of enaminolactone nitrile 3 and primary amines 4a-f in refluxed DMF according to our previous work [1] results in new substituted 2-aminopyridines 5a-f, according Figure 3, results are reported in Table 1.…”