Grignard reduction

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The Grignard reduction is a name reaction in organic chemistry that was named after Victor Grignard . It occurs as a side reaction to the Grignard reaction in the reaction of sterically hindered Grignard compounds with such ketones .

Overview reaction

The Grignard compounds must have to the magnesium for this reaction, at least one hydrogen atom in the β-position. In the Grignard reduction, the carbonyl compound is reduced to a corresponding alcohol . In the Grignard compound , bromine is used as the halogen . Also, chlorine or iodine may be used.

Overview of the Grignard reduction

mechanism

In this reaction, the carbonyl compound and the Grignard compound (alkyl or aryl magnesium halide) give a six-membered transition state . In this transition state, six electrons are shifted cyclically. The oxygen atom of the carbonyl compound takes over the metal to form a metal alkoxide . In addition, an alkene is formed . In the next step, the metal alkoxide is first protonated by dilute aqueous acid and then hydrolyzed . By deprotonation an alcohol produced.

Mechanism of the Grignard reduction

literature