Alum Catalyzed Simple, Efficient, and Green Synthesis of 2-[3-Amino-5-methyl-5-(pyridin-3-yl)-1,5-dihydro-4H-1,2,4-triazol-4-yl]propanoic Acid Derivatives in Aqueous Media

Table 1

Physical characterization data of compounds (5a–i) and (9a).

Entry	R^1	Products	Time (hrs)	Yield (%)	MP (°C)
5a	−CH3		6	90	200
5b	−CH2COOH		7	87	205
5c	−CH2(CH3); CH2CH3		7	87	194
5d			8	88	174
5e	−CH2CH2SCH3		6	90	185
5f	−CH2C6H5		7	88	182
5g	−CH2OH		6	89	198
5h			6	86	197
5i	CH2(CH3)2		7	87	183
9a	—		7	88	190

Reaction Conditions: All the compounds were synthesized by stirring 3-acetyl pyridine 1 (2 mmol), amino acid 2 (2 mmol), thiosemicarbazide (2 mmol), and alum (25 mol%) in water (25 mL) at 80°C for 6-7 hrs.