Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Triethylamine | HCID 8471 | — |
| Reactant | Benzoylhydrazine | HCID 11955 | — |
| Reactant | p-Toluenesulfonic acid monohydrate | HCID 521998 | — |
| Reactant | HCID 6401291 | HCID 6401291 | — |
| Solvent | O-Xylene | HCID 7237 | — |
| Product | HCID 21187546 | HCID 21187546 | 50.9% |
Reaction Steps
A mixture of 3,6-dichloro-4-(piperidin-1-yl)pyridazine (0.55 g, 2.4 mmol), benzoyl hydrazine (370 mg, 2.7 mmol), triethylamine (375 ml, 2.7 mmol) and p-toluenesulphonic acid monohydrate (510 mg, 2.7 mmol) in xylene (mixture of isomers, 10 ml) was stirred and heated at reflux under nitrogen for 24 hours. Upon cooling the xylene was removed in vacuo and the residue was partitioned between dichloromethane and water. The aqueous was further extracted with dichloromethane (×3). The combined extracts were dried (Na2SO4), filtered and evaporated. The residue was purified by chromatography on silica gel, eluting with 30% ethyl acetate/dichloromethane to afford the undesired regioisomer (less polar) (177 mg, 23%) and the title compound (383 mg, 50%) (more polar). Data for the title compound: 1H NMR (250 MHz, CDCl3) δ 1.62-1.86 (6H, m), 3.09-3.13 (4H, m), 7.42 (1H, s), 7.50-7.60 (3H, m), 8.40-8.44 (2H, m).
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
|---|
| Patent number | US06255305B1 |
|---|
| Source dataset | uspto-grants-2001_07 |
|---|
| ORD ID | ord-22efd50c645d4ef0b59106f1ba1be76e |
|---|
| Source note | uspto-grants-2001_07 |
|---|