Synthesis
General procedure for the synthesis of 1,4-dichlorophthalazine from phthaloyl hydrazine: phthaloyl hydrazine (1.68 g, 10 mmol) was added to a stirred solution of phosphoryl chloride (15 ml). The mixture was heated to 110°C and kept for 1 hour. After completion of the reaction (monitored by TLC), the reaction mixture was cooled to room temperature. The mixture was slowly added dropwise to crushed ice and stirred for 10 minutes. Subsequently, the mixture was filtered through a Brinell funnel. The filter cake was washed to neutrality with distilled water and dried in vacuum. 1,4-Dichlorophthalazine (1.85 g, 90.1% yield) was finally obtained as a white solid.
References
[1] Bioorganic and Medicinal Chemistry Letters, 2014, vol. 24, # 4, p. 1236 - 1238
[2] European Journal of Medicinal Chemistry, 2014, vol. 85, p. 235 - 244
[3] Chemical Biology and Drug Design, 2013, vol. 81, # 5, p. 591 - 599
[4] New Journal of Chemistry, 2016, vol. 40, # 7, p. 6070 - 6076
[5] Bioorganic and Medicinal Chemistry Letters, 2016, vol. 26, # 6, p. 1576 - 1579
