Use Coupon: CART20 and get 20% off on all online Study Material

Total Price: R

There are no items in this cart.
Continue Shopping
Get instant 20% OFF on Online Material.
coupon code: MOB20 | View Course list

Get extra R 500 off

				   I want uses of grignard reagent in various fields such as medicine,industrial field.I have searched the net a lot but I havn't got much information about it . 

6 years ago


Answers : (3)


Hi Sunil,

GRIGNARD REACTION In general terms, addition of Grignard reagent to Aldehydes and Ketones is known as the Grignard reaction. It is a reaction of a carbonyl compound with alkyl or arryl Magnesium/Zinc Halide to give an alcohol. Primary, Secondary or Tertiary alcohols may be prepared by the reaction of a suitable carbonyl-containing compound with an alkyl magnesium halide-so called Grignard reagent. The reagent is usually obtained quite readily by adding an alkyl halide to a suspension of magnesium turnings in anhydrous ethers. Initiation of the reaction may require the addition of a few crystals of iodine, the purpose of which may be to form a catalytic amount of Magnesium Iodide or possibly simply to etch the metal surface. As it is important that the iodine should be concentrated at the metal surface the mixture should not be stirred at this stage. Generally used solvents are THF, Dibutyl ether etc.

Formaldehyde gives primary alcohol, other Aldehydes give secondary alcohols, and Ketones give tertiary alcohols by this reaction. The reaction is of very broad scope, and hundreds of alcohols have been prepared by this reaction. The metal used generally is magnesium. But in general Besides Grignard reagents, alkyl-and aryl lithiums and alkyl zinc reagents are also used for attack of carbon on organo-metallic compounds. Organo-tin reagents, aryl lithium, titanium, alluminium are also employed

GR is used in Alkylation, in coupling reactions, for making Esters of Different Functional Groups, Aromatic & Tertiary Thiols etc

ACs like DMBC/DMBCA, DIMETOL, DAMASCONES etc are prepared by GR from many years. Diethyl ether is used as the solvent in many processes in spite of the potential hazards of flammability and formation of explosive peroxides. THF, Dibutyl ether and Diamyl ether have also been used, but these solvents present problems as well.

GR is becoming an important Industrial Process for many ACs productions now a days

Criticalities associated with the Grignard Reaction

Initiation of the reaction

Initiation of the reaction should occur within the first 10-20% addition of the RX solution in ethereal solvent. Evidence for the initiation is large exotherm and a visual change of the magnesium turnings from a bright shiny silver color to a dull gray black. Agitation should be strong enough to shear the magnesium turnings in the reaction mass. Until initiation has been confirmed, no more than 20% of the RX charge should be added to the reactor. Otherwise the large exotherm will release the reaction contents to the atmosphere.

Effect of moisture & Oxygen

Problems are homocoupled product, intra molecular reactions, formation of RMgO2X and noninitiated reaction. Proper manipulation and drying of each component must be carried out. Water in RX and Solvent and Mg must be less than 0.02% and free of Oxygen. Presence of water typically leads to the sudden initiation after all RX has been added. This takes place because the residual water is azeotroped out of the mixture during reflux Or is actually used up by residual Grignard reagent. To prevent this, dry the components properly and manipulate under nitrogen. Addition of small quantity of GR may help for the initiation.

Oxygen will react with GR to form RMgO2X. This peroxo-species can oxidize the other reactants, ligands and catalyst or final product. And the purification problems will arise.

RMgX + H2O ------------------------------à RH + MgX[OH]

Ether and non-polar Hydrocarbons are the generally used solvents, Solvent is selected for yield improvement, stereo chemical and regiochemical control and formation of dialkyl Mg species. The solvent effect is attributed to the solvent’s polarity, basicity, steric hindrance etc.



Grignard reagent PhMgCl was added during the preparation of the catalyst system MgCl2/di-n-butyl phthalate (DNBP)/TiCl4 - AlEt3/diphenyl dimethoxyl silane (DPDMS) to improve its performance. It was found that PhMgCl could enhance both the activity of the catalyst and the isotacticity of the products, but decreased the Ti content of the catalysts under the same preparation conditions. The polymerization kinetics showed that PhMgCl accelerates the decay in the same time that it increased the initial and final polymerization rates..

All the best....

6 years ago

why we can not use calcium other than Mg ?

4 years ago
										why Grignard reagent is so useful in field of organic chemistry?
2 years ago

Post Your Answer

Other Related Questions on Organic Chemistry

List of compound and their uses of all chapter class11 chemistry
Hi, There are so many compounds, I suggest you to refer to NCERT everything is given there Thanks
Nishant Vora 3 months ago
@ rafi there are more than 100 of compounds are avaliable if u will refer to the whole class 11 th chemistry . so, kindly tell of which chapter u required , so, that i can give u of that...
Umakant biswal 3 months ago
Why cold condition is maintained while preparing benzenediazonium chloride from aniline?
In cold solution the nitrogen gas gets off and furst pre-oproduct formed is some oily type product called oily droplets of iodobenzene.
Vikas TU one month ago
Benzene diazonium chloride decomposes very fast so to minimize its decomposition reaction is taken out at low temperature
Amay chugh one month ago
The IUPAC name of the compound shown below is...................................
C is the correct option as here double bond is given more preference then the halogens so the double bond is given priority and among chloro and bromo ,according to the alphabetical order...
Amay chugh 29 days ago
Correct answer is c. so name of this compound is: 3-Bromo-1-Chlorocyclo-hex-1-ene thanks keep posting your doubts
SAHIL one month ago
define IE1 and IE2 , why is IE1 > IE2 for a given atom ? discuss any four factors that affect IE of AN ELEMENT
@ deva ionisation energy or ionisation enthalpy is the enrgy required to remove the most loosely bound electron from an isolated gaseous atom . and IE1 , IE2 , these are the removal of...
Umakant biswal one month ago
Assuming pure 2s and 2p orbitals of Carbon are used in forming CH4 molecule, which if the following is false? (a) 3 C-H bonds will be at right angles (b) 1 C-H bond will be weaker than other...
CH4 has tetrahederal structure orientation with sp3 hybridization. hece 4 C-H bonds would be at equal angles with each C-H bond. and that would be 109.5 degree and that is practically...
Vikas TU one month ago
Electronic transistion in He + ion takes place from n 1 to n 2 shell such that: 2n 2 +3n 1 =18 2 n 2 -3n1=6 What will be the totalno. of photons emitted when electron transit to n1 shell?
Dear Mudit, Remmeber these two formulaes: 1) Maximum no. of photons they eemits if they return to ground state is: n(n-1)/2 2) And for n2 to n1 level, formmulae is: (n2-n1)(n2-n1+1)/2 gives ...
Vikas TU 2 months ago
By solving I got n1=2 and n2=6 By applying the formula I got the answer 1 while the answer given in book is 10. So help me out with this.
Mudit 2 months ago
Solve both the eqns. and get the value of n1 and n2. Then to know total number of photons to n1 state, Apply the fomulae: n1(n1-1)/2
Vikas TU 2 months ago
View all Questions »

  • Complete JEE Main/Advanced Course and Test Series
  • OFFERED PRICE: R 15,000
  • View Details
Get extra R 3,750 off

Get extra R 500 off

More Questions On Organic Chemistry

Ask Experts

Have any Question? Ask Experts

Post Question

Answer ‘n’ Earn
Attractive Gift
To Win!!!
Click Here for details