Nitration

Nitration occurs with aromatic organic compounds via an electrophilic substitution mechanism involving the attack of the electron-rich benzene ring by the (nitryl) nitronium ion.

Related Topics:
Aromatic organic compounds - Electrophilic substitution - Benzene - Nitronium ion

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Benzene is nitrated by refluxing with concentrated sulfuric acid and concentrated nitric acid at 50°C.

Related Topics:
Nitric acid - C

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(1) 2H2SO4 + HNO3 → 2HSO42- + NO2+ + H3O+

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(2) C6H6 + NO2+ → C6H5NO2 + H+

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(3) H+ + H3O+ + 2HSO42- → H2O + 2H2SO4

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The sulfuric acid is regenerated and hence acts as a catalyst.

Related Topics:
Sulfuric acid - Catalyst

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The formation of a nitronium ion (the electrophile) from nitric acid and sulfuric acid is shown below:

Related Topics:
Nitric acid - Sulfuric acid

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Selectivity is always a challenge in nitrations, Fluorenone nitration is selective and yields a tri-nitro compound or tetra-nitro compound by tweaking reaction conditions just slightly. Another example of trinitration can be found in the synthesis of phloroglucinol.

Related Topics:
Fluorenone - Phloroglucinol

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Other nitration reagents include nitronium tetrafluoroborate which is a true nitronium salt. This compound can be prepared from hydrogen fluoride, nitric acid and boron trifluoride . Aromatic nitro compounds are important intermediates to anilines by action of a reducing agent.

Related Topics:
Nitronium tetrafluoroborate - Hydrogen fluoride - Nitric acid - Boron trifluoride - Aniline - Reducing agent

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