1(2H)-Phthalazinone is an organic compound with the formula C₈H₆N₂O, and its systematic name is the same with the product name. With the CAS registry number 119-39-1, it is also named as Benzo[d]pyridazin-1(2H)one. It belongs to the product categories of Miscellaneous; Aldehyde. Its EINECS number is 204-319-8. In addition, the molecular weight is 146.15. This chemical is used as biochemical reagents. Its classification code is Mutation data. It can be used as Hydralazine hydrochloride intermediate.

Physical properties of 1(2H)-Phthalazinone are: (1)ACD/LogP: 0.75; (2)# of Rule of 5 Violations: 0; (3)ACD/LogD (pH 5.5): 0.75; (4)ACD/LogD (pH 7.4): 0.75; (5)ACD/BCF (pH 5.5): 2.19; (6)ACD/BCF (pH 7.4): 2.19; (7)ACD/KOC (pH 5.5): 60.95; (8)ACD/KOC (pH 7.4): 60.95; (9)#H bond acceptors: 3; (10)#H bond donors: 1; (11)#Freely Rotating Bonds: 0; (12)Polar Surface Area: 41.46 Å²; (13)Index of Refraction: 1.667; (14)Molar Refractivity: 41.272 cm³; (15)Molar Volume: 110.881 cm³; (16)Polarizability: 16.362×10^-24cm³; (17)Surface Tension: 52.7 dyne/cm; (18)Density: 1.318 g/cm³; (19)Flash Point: 209.9 °C; (20)Enthalpy of Vaporization: 70.39 kJ/mol; (21)Boiling Point: 423.4 °C at 760 mmHg; (22)Vapour Pressure: 9.11E-08 mmHg at 25°C.

Preparation of 1(2H)-Phthalazinone: this chemical can be prepared by 2-formyl-benzoic acid. This reaction will need reagents hydrazine sulfate, sodium acetate and solvent H₂O. The yield is about 100%.

Uses of 1(2H)-Phthalazinone: it can be used to produce 1-bromo-phthalazine at the temperature of 130 °C. It will need reagent POBr₃ with the reaction time of 30 min. The yield is about 58%.

When you are using this chemical, please be cautious about it as the following:
This chemical is irritating to eyes, respiratory system and skin. It is harmful if swallowed. It has a possible risk of irreversible effects. You should not breathe dust. In case of contact with eyes, you should rinse immediately with plenty of water and seek medical advice. When using it, you need wear suitable protective clothing, gloves and eye/face protection, and you must avoid contact with skin and eyes.

You can still convert the following datas into molecular structure:
(1)SMILES: O=C1c2ccccc2\C=N/N1
(2)Std. InChI: InChI=1S/C8H6N2O/c11-8-7-4-2-1-3-6(7)5-9-10-8/h1-5H,(H,10,11)
(3)Std. InChIKey: IJAPPYDYQCXOEF-UHFFFAOYSA-N

The toxicity data is as follows: