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Chemist
Inventor of the Grignard Reagent
Co-laureate of the Nobel Prize in Chemistry, 1912
1871-1935

Victor Grignard was the inventor of the Grignard Reagent that is one of the first reactions learned by any student of organic chemistry, and is very useful for combining two organic molecules. For this he was awarded half the Nobel Prize in Chemistry in 1912, the other half going to fellow French chemist Paul Sabatier, who developed another extremely useful reaction still used today: hydrogenation on metallic (eg, platinum or palladium) catalysts.

Grignard received a degree in mathematics from the University of Lyons in 1894, and in 1899 he was working in the lab of Philippe Barbier when he began to figure out the Grignard reaction. Let me take a moment to explain what this is:

The Grignard Reagent (or simply a "grignard", pronounced "grin-yard") is an organometallic compound that can be made to attach itself to an electrophile. First, let's make a grignard reagent. We start with an alkyl bromide (a chain of carbons with a bromine, which is one of the halogens that would work), and add magnesium (which I've put in bold):

                       dry
CH3CH2CH2Br  +  Mg   ------->   CH3CH2CH2MgBr
                      ether

Note the words on the arrows: this reaction must be carried out in the presence of ether, which stabilizes the Mg in the transition state; also, it must be done bone dry. After we look at what you can do with a grignard, we will see why.

So now, the particular carbon that is attached to the MgBr is very nucleophilic - what this means is that it wants to "attack" some nucleus, preferably a carbon or hydrogen. It acts much like a carbanion. Let's say we want to make a carboxylic acid. We can combine our grignard with plain old carbon dioxide to get it!

CH3CH2CH2MgBr  +  O=C=O   ------> CH3CH2CH2-C=O
                                            |
                                            OMgBr

From there it is simple to replace the MgBr with a hydrogen to make this a proper carboxylic acid (with a -COOH group). Now, look what would happen if we allowed the grignard to react with water instead (ie, if we don't keep the equipment bone dry):

CH3CH2CH2MgBr  +  H2O   ------>  CH3CH2CH3  +  MgBrOH

The grignard reacts with the water by pulling off a hydrogen, and then we have no more grignard, just propane, which is much less interesting.

Grignard's reaction is a useful one, so useful that by the time he died in 1935, there were over 6,000 references to it in the literature. KissThis requested that I name some of the uses of the grignard, but that's somewhat like asking what are the uses of glue. You use it to glue things together. The grignard reaction is a way of making the organic molecule of your choice able to attack (and stick to) another organic molecule; all the target molecule needs is an electrophilic carbon. Grignard's is a very simple and basic reaction, one of the first tools taught to students of organic chemistry. Grignard used his reagents to prepare and study the more exotic alcohols, ketones, keto-esters, nitriles, and terpenes.

Grignard published over 170 papers, and at the time of his death was working on the 5th and 6th volumes of his Treatise on Organic Chemistry. Two years later, two of his students published a Survey of Organic Chemistry based on Grignard's lectures. His other research interests also happened to include the area in which his co-laureate Paul Sabatier won his prize: catalytic hydrogenation.

  • 1871 - Born in Cherbourg, France.
  • 1894 - Received his Licencié ès Sciences Mathématiques from Lyons.
  • 1901 - Received his Docteur ès Sciences de Lyons with thesis work on organometallics
  • 1901 - Received the Cahours Prize.
  • 1902 - Received the Berthelot Medal and the Cahours Prize.
  • 1905 - Received the Prix Jecker.
  • 1912 - Received the Nobel Prize in Chemistry with Paul Sabatier and the Lavoisier Medal.
  • 1933 - Appointed Commandeur of the Légion d'Honneur.
  • 1935 - Died in Lyons.

This writeup is part of Everything Quests: The Nobel Prize winners

References and further reading:
http://www.nobel.se/chemistry/laureates/1912/grignard-bio.html
http://www.sunderland.ac.uk/~hs0bcl/org3.htm

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