CH 12-4: Performing a Grignard Synthesis-II
•Study the target molecule and the list of available reagents.
•Locate the new bond in the target molecule and draw a “dot” on the
alcohol carbon.
•Is the target a 1o, 2o, or 3o alcohol? Do you need an aldehyde, ketone,
ester or epoxide? If symmetrical alkyl groups at the alcohol carbon,
then use an ester.
•From the reagent list (stockroom) identify the reactants needed to
make the target molecule.
•Which reactant will you use to make the Grignard reagent? Convert to
an alkyl halide, if necessary.
•Step #1: React alkyl halide with Mg in ether to make Grignard Reagent.
•Step #2: React Grignard reagent with an aldehyde, ketone, ester, or
epoxide.
•Step #3: Acid/base neutralization.
Grignard Example #1 (ketone  3o alcohol)
(3o alcohol)
Grignard Example #2 (aldehyde  2o alcohol)
(2o alcohol)
Grignard Example #3 (ester  3o alcohol)
(3o alcohol)
Grignard Example #4 (epoxide  1o, 2o, or 3o alcohol)
R=R’=H (1o alcohol)
R=H, R’=alkyl (2o alcohol)
R=R’=alkyl (3o alcohol)