Search results
Results from the WOW.Com Content Network
Likewise, it is also prone to oxidation: while freshly purified aniline is an almost colorless oil, exposure to air results in gradual darkening to yellow or red, due to the formation of strongly colored, oxidized impurities. Aniline can be diazotized to give a diazonium salt, which can then undergo various nucleophilic substitution reactions.
Some competitive oxidation of the nitrogen has been observed. [3] Behrman has shown that the first intermediate in the Boyland–Sims oxidation is the formation of an arylhydroxylamine-O-sulfate (2). [5] Rearrangement of this zwitterionic intermediate forms the ortho-sulfate (5), which then hydrolyses to form the ortho-hydroxyl aniline.
Nitrosobenzene can also be prepared by oxidation of aniline using peroxymonosulfuric acid (Caro's acid) [6] or potassium peroxymonosulfate under biphasic conditions. [7] It is usually purified by sublimation or by steam distillation, where it comes over as a green liquid that solidifies to a colorless solid.
Oxidative stress mechanisms in tissue injury. Free radical toxicity induced by xenobiotics and the subsequent detoxification by cellular enzymes (termination).. Oxidative stress reflects an imbalance between the systemic manifestation of reactive oxygen species and a biological system's ability to readily detoxify the reactive intermediates or to repair the resulting damage. [1]
Monoamine oxidases (MAO) (EC 1.4.3.4) are a family of enzymes that catalyze the oxidation of monoamines, employing oxygen to clip off their amine group. [1] [2] They are found bound to the outer membrane of mitochondria in most cell types of the body.
Oxidation response is stimulated by a disturbance in the balance between the production of reactive oxygen species and antioxidant responses, known as oxidative stress. Active species of oxygen naturally occur in aerobic cells and have both intracellular and extracellular sources.
Acetanilide can be produced by reacting acetic anhydride with aniline: [7]. C 6 H 5 NH 2 + (CH 3 CO) 2 O → C 6 H 5 NHCOCH 3 + CH 3 COOH. The preparation used to be a traditional experiment in introductory organic chemistry lab classes, [8] but it has now been widely replaced by the preparation of either paracetamol or aspirin, both of which teach the same practical techniques (especially ...
Aniline absorbs in the K (220 - 250 nm) and the B (250 - 290 nm) bands exhibited by benzenoid compounds. The K and B bands arise from π to π* transitions as a result of the a group containing multiple bond being attached to the benzene ring. When dissolved in ethanol, λ max for aniline is 230 nm, but in dilute aqueous acid λ max is 203 nm ...