A solution of carbonyl compound was added to the Grignard reagent.

However, with hindered Grignard reagents, the reaction may proceed by single-electron transfer.

Grignard reagents will react with a variety of derivatives.

The Grignard reagent thus prepared was cooled to 0°C before the addition of carbonyl compound. The solution became cloudy since the Grignard reagent precipitated out.

The Rate Constants for the Carboxylation of Grignard Reagents

Many methods have been developed to initiate sluggish Grignard reactions. Mechanical methods include crushing of the Mg pieces in situ, rapid stirring, and of the suspension. , , and are commonly employed activating agents. The use of 1,2-dibromoethane is particularly advantageous as its action can be monitored by the observation of bubbles of . Furthermore, the side-products are innocuous:

The most common application is for alkylation of aldehydes and ketones, as in this example (click on the picture to see the entire reaction):


Formation of Grignard Reagents from Organic Halides

Grignard reagents are formed via the action of an alkyl or aryl halide on . The reaction is conducted by adding the organic halide to a suspension of magnesium in an , which provides required to stabilize the . Typical solvents are and . Oxygen and protic solvents such as water or alcohols are not compatible with Grignard reagents. The reaction proceeds through .

Mechanisms of Grignard reagent addition to ketones


Grignard reactions often start slowly. As is common for reactions involving solids and solution, initiation follows an induction period during which reactive magnesium becomes exposed to the organic reagents. After this induction period, the reactions can be highly . Alkyl and aryl and are common substrates. are also used, but are generally unreactive, except with specially activated magnesium, such as .

Mechanisms of Grignard reagent addition to ..

Grignard reagents are formed via the action of an alkyl or aryl halide on . The reaction is conducted by adding the organic halide to a suspension of magnesium in an , which provides required to stabilize the . Typical solvents are and . Oxygen and protic solvents such as water or alcohols are not compatible with Grignard reagents. The reaction proceeds through .

Grignard Synthesis of Methamphetamine ..

An example of the Grignard reaction is a key step in the industrial production of (currently used for the treatment of estrogen receptor positive breast cancer in women) :

• The synthesis of Grignard reagent must take place in ..

In a reaction involving Grignard reagents, it is important to ensure that no water is present, which would otherwise cause the reagent to rapidly decompose. Thus, most Grignard reactions occur in solvents such as anhydrous or , because the oxygen of these solvents stabilizes the magnesium reagent. The reagent may also react with oxygen present in the atmosphere, inserting an oxygen atom between the carbon base and the magnesium halide group. Usually, this side-reaction may be limited by the volatile solvent vapors displacing air above the reaction mixture. However, it may be preferable for such reactions to be carried out in or atmospheres, especially for smaller scales.