Advance organic chemistry topic

1. 1,2 difunctional compounds
Now in organic chemistry a common problem is knowing how to design
the synthesis route for a substance. It is nice to be able to buy chemicals
ready made but sometimes we need to be able to make things for
ourselves. Sometimes the price of the readymade substance is too high or it
might be impossible to find someone who will sell it.
The best way to plan the synthesis is often to look at the carbon
framework of the molecule and look for ways in which we can use
chemistry to cut up the molecule into more simple units. I generally advise
you to look for bond breaking close to the functional groups.
If you see two carbonyl groups, two alcohols or a ketone and an alcohol
next to each other then we can consider breaking the bond between the
two carbons bearing these groups. If we look at the synthesis of the CyMe4
diketone used in BTP and BTBP chemistry we disconnect the molecule at
this point to form a synthon.
A synthon is a entity which can be an imaginary one which can not exist in
real life. We can break the molecule up to make an imaginary diradical.
.
If we can think of a combination of reagents which reacts like the way that
our synthon would then we can make some progress. In this case at
Reading we used the diester as a synthetic equivalent of the diradical

2. What we used was the reaction of the diester with sodium metal in toluene
with trimethyl silyl chloride present. What happens in this reaction is that
the ester groups accept an electron from the sodium metal to form radical
anions which then dimerise as they are formed on the surface of the
sodium metal
After the dianion forms it will react with the chlorosilane to form the
following type of compound.

3. What we can now do is one of three things, we can treat the compound
with aqueous acid and then convert it into the 1,2-ketoalcohol. We can use
hydrogen gas and a catalyst to hydrogenate the carbon-carbon double
bond. This will give us a protected dialcohol. Finally we can oxidize it with
bromine to form the 1,2-diketone which we want.
There are other reactions which form 1,2 difunctional molecules. For
example we can react aromatic aldehydes with a small amount of cyanide to
form 2-hydroxyketones. Also we can react ketones with magnesium
amalgam to form 1,2-diols in the pinacol reaction.