6-BROMOPHTHALAZIN-1(2H)-ONE

134C (954 mg, 4.17 mmol) was suspended in isopropyl alcohol (10 mL). The solution was heated at 90° C. for 1.5 h. Hydrazine monohydrate (0.4 mL, 8.25 mmol) was added in 4 increments. The resulting suspension was filtered and washed with isopropyl alcohol to give 134D (813 mg, 87percent) as a beige solid. LC-MS m/z: 227.12 (M+H)6-Bromo-2H-phthalazin-l -one; A mixture of 5-bromo-3-hydroxy-2, 3-dihydro-isoindol-l-one (15.75 g, 69.06 mmol) and hydrazine hydrate (70 mL, 1439.2 mmol) was heated at 95 To a stirred solution of 5-bromo-3-hydroxyisoindoline-1-one (1.0 g, 4.40 mmol) in water, was added hydrazine hydrate (0.45 g, 8.80 mmol) and heated to 95° C. for 5 h. The reaction mixture was cooled to ambient temperature, filtered and washed with diethyl ether and pentane (1:1) to afford the title compound as a white solid that was used in the next step without further purification (0.5 g): ESIMS m/z 225.15 ([M+H]To a stirred solution of 5-bromo-3- hydroxyisoindoline-1-one (1.0 g, 4.40 mmol) in water, was added hydrazine hydrate (0.45 g , 8.80 mmol) and heated to 95°C for 5 h. The reaction mixture was cooled to RT, filtered and washed with diethyl ether and pentane (1: 1) to afford the title compound as a white solid that was used in the next step without further purification (0.5 g): ESIMS m/z 225.15 ([M+H]j0201] 6-l3romophthalazin-1(2H)-one (22b) In a 25 mE round bottom flask was dissolved 3, 5-dibromoisobenzoth- ran-1(3H)-one (302 mg, 1.04 mmol) in ethanol (10 mE). Hydrazine monohydrate (0.25 mE, 5.18 mmol) was then added via a syringe and the solution was refluxed for 1.5 hours. The solution was cooled to room temperature and ice water (30 mE) was added to the reaction mixture. The precipitate was vacuum filtered and dried under a vacuum overnight to yield 22b as a white solid in 73percent yield. ‘H NMR (500 MHz, DMSO-d5) ö 12.78 (br. s., 1H), 8.33 (s, 1H), 8.23 (d, J=2.0 Hz, 1H), 8.12 (d, J=8.3 Hz, 1H), 8.00 (dd, J=8.3, 2.0 Hz, 1H). ECMS found 224.9 [M+H].To a stirred solution of commercially available 2a (100mg, 0.444 mmol) in DMF was added NaH (32 mg, 1.333 mmol) at 0 oC. After stirring for 20 min, 3-methoxybenzyl bromide (62 muL, 0.444 mmol) was added into the cooled solution. Then the reaction was transferred to RT and kept stirring for 12h. The reaction mixture was concentrated to dryness under vacuum and then partitioned between CH2Cl2 and water. The organic layer was washed with brine and dried over MgSO4. The organic phase was concentrated to dryness under vacuum and puried via a ash chromatography silica gel plate (20 × 20 cm) to afford intermediate 3a (petroleum ether/ethyl acetate, 2/1) in 45% yield as a pale yellow solid. 1H NMR (400 MHz, DMSO) delta 8.42 (s, 1H), 8.26 (d, J = 1.8 Hz, 1H), 8.18 (d, J = 8.5 Hz, 1H), 8.03 (dd, J = 8.5, 1.9 Hz, 1H), 7.24 (t, J = 7.8 Hz, 1H), 6.87 (s, 2H), 6.85 (dd, J = 7.7, 2.9 Hz, 1H), 5.28 (s, 2H), 3.72 (s, 3H). (0.80 g, 3.55 mmol), A solution of cesium carbonate (2.89 g, 8.86 mmol) and 2-chloromethyloxazole (0.50 g, 4.25 mmol) in N, N-dimethylformamide (10 mL) was stirred at 50 C for 5 h. The reaction system was cooled to room temperature, poured into water, and the solid was collected by filtration. Wash the filter cake with water and petroleum ether, respectively. Drying under reduced pressure gave Compound 3.1 (0.84 g, yield: 78%) as a yellow solid.

Molecular Weight:225.04
XLogP3:1.4
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:2
Exact Mass:223.95853
Monoisotopic Mass:223.95853
Topological Polar Surface Area:41.5
Heavy Atom Count:12
Complexity:229
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes