Yield:144402-92-6 85%

Reaction Conditions:

with hydrazine hydrate in methanol; for 4 h;Reflux;

Steps:

1

After the compound A-1 (6.4g, 30mmol) and hydrazine monohydrate (6mL, 120mmol) dissolved in 150mL of methanol, was stirred under reflux for 4 hours. The resulting solid was filtered off down to room temperature, dried, washed with 20mL of methanol and 20mL of water, to prepare a compound of Formula A-2 (5.3g, 85%).

References:

KR101640637,2016,B1 Location in patent:Paragraph 0093-0096