Use of the grignard solution, Chemistry

Use of the Grignard solution to prepare 2,2,6-trimethyl-5-phenylheptan-3-one:

Prepare a solution of your enone (5.64 g; 0.030 moles) in dry ether (30 mL) and add it to the dropping funnel. Add it dropwise, over 30 min, to the stirred and ice-cooled solution of 2-propyl magnesium bromide. When addition is complete, remove the slush-bath and continue stirring for a further 30 min.

Hydrolyse the mixture by pouring it cautiously onto a mixture of ammonium chloride (16 g) and crushed ice (70 g) in a beaker, stirring as you do so with a glass rod. When the ice has melted, separate the two layers and extract the aqueous layer with ether (2 x 50 mL; there is no need to use dry ether at this stage: why not?) keep the ether layer. Back-wash the combined ethereal layers with saturated brine (40 mL)

Dry the ether layer over anhydrous magnesium sulphate, filter and evaporate thoroughly (use a clean rotary evaporator!) to dryness, in a tared RB flask. Determine the weight of the crude product obtained.

Recrystallise your product (even if it is at present a liquid) from a mixture of ethanol/water (95:5, v/v), using 2 mL of solvent for each gram of product. If no crystals appear on cooling the filtered solution in ice, add a seed crystal of product (available from a demonstrator) to induce crystallisation. After allowing a thick precipitate to form, collect it on a Hirsch funnel, filtering rapidly to avoid redissolving. Pull the cake as dry as possible, then finally dry (24 hr) on a watch glass, in air, in a cupboard.

Posted Date: 2/11/2013 6:35:52 AM | Location : United States







Related Discussions:- Use of the grignard solution, Assignment Help, Ask Question on Use of the grignard solution, Get Answer, Expert's Help, Use of the grignard solution Discussions

Write discussion on Use of the grignard solution
Your posts are moderated
Related Questions
is relation a=2r+ + 2r- correct for bcc

what is conductometry and how it work

Test Ethyl cyanide Ethyl isocyanide Smell Strong but pleasant Extremely unpleasant Dipole moment

?H value obtained for the reaction NH3 + HCl –› NH4Cl using the thermodynamic data in your lab procedure?


The covalent bond produced by the unequal sharing of electrons among the two atoms is known as polar covalent bond.

Which of the following is not true in Rutherford's nuclear model of atom: (1) Protons and neutrons are present inside nucleus (2) Volume of nucleus is very small as compared

ionic equation by ionelectron method (half reaction)

what are the applications of radioactivity in forensics, agriculture, medicine, engineering, and geology

#between p-amino aniline &p-methyl aniline which is more basic?