4-(4-Nitrophenylazo)resorcinol (74-39-5)

The IUPAC name of 1,3-Benzenediol, 4-(2-(4-nitrophenyl)diazenyl)- is 3-hydroxy-4-[(4-nitrophenyl)hydrazinylidene]cyclohexa-2,5-dien-1-one. With the CAS registry number 74-39-5, it is also named as 4-(4-Nitrophenyl)azoresorcinol. The product's categories are analytical chemistry; azo compounds; azobennzenes, etc. (chelating reagents); chelating reagents. It is dark red to brown crystalline powder which is stable and incompatible with strong oxidizing agents, strong bases. The solution is reddish purple when in dilute alkali. This chemical is slightly soluble in acetone, acetic acid and toluene, and insoluble in water. In addition, 1,3-Benzenediol, 4-(2-(4-nitrophenyl)diazenyl)- is used as sensitive reagent for the determination of magnesium and non-aqueous titration indicator.
  
The other characteristics of this product can be summarized as: (1)ACD/LogP: 2.82; (2)ACD/LogD (pH 5.5): 2.82; (3)ACD/LogD (pH 7.4): 2.61; (4)ACD/BCF (pH 5.5): 81.37; (5)ACD/BCF (pH 7.4): 50.37; (6)ACD/KOC (pH 5.5): 809.39; (7)ACD/KOC (pH 7.4): 501; (8)#H bond acceptors: 7; (9)#H bond donors: 2; (10)#Freely Rotating Bonds: 5; (11)Index of Refraction: 1.665; (12)Molar Refractivity: 66.22 cm³; (13)Polarizability: 26.25×10^-24 cm³; (14)Surface Tension: 64.2 dyne/cm; (15)Enthalpy of Vaporization: 80.91 kJ/mol; (16)Vapour Pressure: 5.46E-11 mmHg at 25°C; (17)Rotatable Bond Count: 2; (18)Tautomer Count: 12; (19)Exact Mass: 259.059306; (20)MonoIsotopic Mass: 259.059306; (21)Topological Polar Surface Area: 108; (22)Heavy Atom Count: 19.

Preparation of 1,3-Benzenediol, 4-(2-(4-nitrophenyl)diazenyl)-: 138g p-nitroaniline dissolved in 250ml hot concentrated hydrochloric acid, then cooling to 0-5 °C, dropping saturated aqueous solution which contains 85g nitrite under stirring and the temperature is not more than 5 °C. Adding 100g resorcinol and dilute alkali solution to this diazonium salt solution. After filtering and drying of this coupling product, recrystallization with alcohol, then we can get the product.

When you are using this chemical, please be cautious about it as the following:
It is irritating to eyes and skin. In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. If you want to contact this product, you must wear suitable protective clothing.

People can use the following data to convert to the molecule structure.
1. SMILES: Oc2cc(O)ccc2/N=N/c1ccc(cc1)[N+]([O-])=O;
2. InChI: InChI=1/C12H9N3O4/c16-10-5-6-11(12(17)7-10)14-13-8-1-3-9(4-2-8)15(18)19/h1-7,16-17H.

The following are the toxicity data which has been tested.