Nitrosobenzene

Structural formula
General
Surname	Nitrosobenzene
other names	Nitrosobenzene
Molecular formula	C 6 H 5 NO
Brief description	Monomer : green - Dimer : colorless crystals
External identifiers / databases
CAS number 586-96-9 EC number 209-591-1 ECHA InfoCard 100.008.721 PubChem 11473 Wikidata Q419621
properties
Molar mass	107.11 g mol −1
Physical state	firmly
Melting point	68 ° C
safety instructions
GHS labeling of hazardous substances danger H and P phrases H: 301-312-332 P: 280-301 + 310
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Nitrosobenzene is the simplest aromatic nitroso compound . It contains the nitroso group –N = O, which is linked to a phenyl group ( benzene residue ).

Nitrosobenzene forms pungent, colorless crystals in which it is present as a mesomeric-stabilized dimer with the empirical formula (C ₆ H ₅ NO) ₂ . The green monomer is created when the dimer is dissolved , melted and evaporated .

history

Nitrosobenzene was first synthesized by A. von Baeyer by reacting diphenyl mercury with nitrosyl bromide:

${\displaystyle \mathrm {(C_{6}H_{5})_{2}Hg+BrNO\longrightarrow C_{6}H_{5}NO+C_{6}H_{5}HgBr} }$

It was also reported by H. Caro by oxidation of aniline with peroxomonosulfuric shown ( "Caro's acid").

Manufacturing

Nitrosobenzene can best be produced by oxidizing N -phenylhydroxyl amine with potassium dichromate and sulfuric acid:

${\displaystyle \mathrm {C_{6}H_{5}NHOH\longrightarrow C_{6}H_{5}NO+H_{2}O} }$

properties

The heat of decomposition determined by DSC is −88 kJ · mol ⁻¹ or −823 kJ · kg ⁻¹ .

Individual evidence

1. ↑ ^{a b c} H. Beyer, W. Walter: Textbook of organic chemistry . 20th ed., Hirzel, Stuttgart, 1984. p. 527.
2. ↑ ^{a b} Data sheet nitrosobenzene from Sigma-Aldrich , accessed on April 16, 2011 ( PDF ).
3. ↑ Grewer, T .; Klais, O .: Exothermic decomposition - investigations of the characteristic material properties , VDI-Verlag, series "Humanisierung des Arbeitsleben", Volume 84, Düsseldorf 1988, ISBN 3-18-400855-X , p. 9.

literature

• Adolf Baeyer: Nitrosobenzene and Nitrosonaphthalene. In: Reports of the German Chemical Society. 7, 1874, pp. 1638-1640, doi : 10.1002 / cber.187400702214 .
• H. Beyer, W. Walter: Textbook of organic chemistry . 20th ed., Hirzel, Stuttgart, 1984. pp. 527-528.
• H. Caro. In: Zeitschrift für angewandte Chemie 11 (1898). S. 845 ff. Doi : 10.1002 / anie.18980113602