A mixture of I (0.01 mol) in concentrated HCl (10 ml) was cooled with stirring to 0 5°C under ice, and cooled sodium nitrite solution (2.5 g in 10 mL of water) was added to it dropwise during 30 minutes.
N - 6-Bromo[1,2,4]triazolo[1,5- a ]pyridinyl cyclohexanecarboxamide (18): A mixture of triazolopyridine 16 (1.49 g, 7.0 mmol) and DMAP (85 mg, 0.7 mmol, 10 mol %) in pyridine (anhydrous, 30 mL) was cooled to 0 °C under argon, cyclohexylcarbonyl chloride (0.94 mL, 1.03 g, 7.0 mmol) was added dropwise, and the mixture was warmed to RT and stirred for 17 h.
To a flame-dried 500 mL 4-necked flask, was charged n-octylbenzene 24.39 g (0.128 mol), hexane 158 mL, and the reaction mixture was cooled to 5°C.
Triazolopyridine 16 (1 equiv), DMAP (10 mol %), and pyridine (anhydrous, 7 mL mmol−1) was cooled to 0 °C under argon, and the acid chloride (1 equiv) was added dropwise.
The reaction mixture was cooled; then malononitrile (0.66 mg, 0.01 mol) was added, followed by catalytic amount of pyridine (2 mL) portion wise and left to reflex till solid formed.
After the reaction, the mixture was cooled to 60 °C before being neutralized with 3 mol L−1 acetic acid.
A mixture of 3 (0.01 mol) and hydrazine hydrate (0.03 mol) in ethanol (20 mL), was heated under reflux for 2 h, the reaction mixture was cooled, then poured into ice/water solution and acidified with hydrochloric acid (1 N).
The resulting grey suspension was cooled to 0 °C and 1,2-dichloroethane (15.8 mL, 0.201 mol) was added slowly.
was added to a mixture of keto ester and catalyst 1o (2 mol-%) in m-xylene (20 mL/mmol keto ester) and the mixture was cooled to −10 °C.
The reaction solution was cooled in ice water bath, and acidified with HCl (3 mol/L).
