4-Bromo-6-chloro-2,3-dihydropyridazin-3-one → 6-chloro-4-(1-ethyl-1H-pyrazol-3-ylamino)-2-methylpyridazin-3(2H)-one

Participants

Role	Name	HCID	Charge
Reactant	4-Bromo-6-chloro-2,3-dihydropyridazin-3-one	HCID 11586522	—
Reactant	1-ethyl-1H-pyrazol-3-amine	HCID 12198109	—
Reactant	6-chloro-4-(5-methyl-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazin-2-ylamino)pyridazin-3(2H)-one	HCID 58540316	—
Product	6-chloro-4-(1-ethyl-1H-pyrazol-3-ylamino)-2-methylpyridazin-3(2H)-one	HCID 68057973	94%

Reaction Steps

Using the same general procedure as described for the preparation of 101m, reaction of 1-ethyl-3-amino-1H-pyrazole (500 mg, 4.50 mmol) with 4-bromo-6-chloropyridazin-3(2H)-one (1.00 g, 4.50 mmol) afforded 102g in 94% yield (1.07 g) as an amorphous yellow solid: mp 173-175° C.; 1H NMR (300 MHz, DMSO-d6) δ 9.61 (s, 1H), 7.71 (s, 1H), 7.64 (d, J=2.4 Hz, 1H), 6.19 (d, J=2.4 Hz, 1H), 4.10 (q, J=7.2 Hz, 2H), 3.65 (s, 3H), 1.37 (t, J=7.2 Hz, 3H); MS (ESI+) m/z 254.0 (M+H).

Provenance & Evidence

DOI	10.6084/m9.figshare.5104873.v1
Patent number	US08975260B2
Source dataset	uspto-grants-2015_03
ORD ID	ord-ec2c0a4c4f21432aa2a14ab2811ee4fe
Source note	uspto-grants-2015_03