1,2,4-Triazines have been prepared from the one-pot condensation reaction of acid hydrazide (1), ammonium acetate and dicarbonyl compounds (2) on the surface of silica gel in the presence of triethylamine under microwave irradiation.
Cycloaddition Reactions with Azabenzenes, XVIII. Synthesis of [2]Pyrindines
The reaction of 1,2,4-triazines (1) and 1-cyclopentenylpyrrolidine (2) afforded 6,7-dihydro-5H-[2]-pyrindines (3) in good yields. Oxidation of 3 to the N-oxides (4), reaction of 4 with acetic anhydride to 5-acetoxy-6,7-dihydro-5H-[2]pyrindines (5) and elimination of acetic acid afforded [2]pyrindines (7). 2-Methyl-2H-[2]pyrindines (9) were also prepared.