This is so that you are sure that the chlorine is part of the methyl group and not somewhere else on the ring.
Benzene ring with ketone group.
Bn similar to the phenyl group is formed by manipulating the benzene ring.
A variant on this which you may need to know about is where one of the hydrogens on the ch 3 group is replaced by a chlorine atom.
In an electrophilic aromatic substitution reaction existing substituent groups on the aromatic ring influence the overall reaction rate or have a directing effect on positional isomer of the products that are formed.
Remember that you get a methyl group ch 3 by removing a hydrogen from methane ch 4.
In the case of the benzyl group it is formed by taking the phenyl group and adding a ch 2 group to where the hydrogen was removed.
The benzyl group abbv.
Most importantly we have the first part of the final product of the reaction which is a ketone.
Notice the brackets around the chloromethyl in the name.
Aromatic compounds with only one group attached to the benzene ring.
In doing so the original alcl 3 is regenerated for use again along with hcl.
If neither is hydrogen the compound is a ketone.
The carbonyl group is on carbon 3 and the methyl group is on carbon 5.
Aldehydes and ketones are organic compounds which incorporate a carbonyl functional group c o.
An electron donating group edg or electron releasing group erg z in structural formulas is an atom or functional group that donates some of its electron density into a.
Like a methyl or an ethyl group a phenyl group is always attached to something else.
Why the reaction is important.
Although the product is a ketone a compound containing a carbon oxygen double bond with a hydrocarbon group either side it is easily converted into other things.
A benzene ring was formed to connect a carbonyl group of various methyl ketones with a π conjugated group through a p phenylene linker.
During the third step alcl 4 returns to remove a proton from the benzene ring which enables the ring to return to aromaticity.
Methyl ketones and streptocyanines were used as the c1 and c5 sources respectively in the 5 1 annulation which could form donor π acceptor molecules.
The carbon atom of this group has two remaining bonds that may be occupied by hydrogen alkyl or aryl substituents.
In cyclic ketones numbering of the atoms of the ring begins with the carbonyl carbon as number 1.
An alkyl group can be added to a benzene molecule by an electrophile aromatic substitution reaction called the friedel crafts alkylation reaction.
One example is the addition of a methyl group to a benzene ring.
If at least one of these substituents is hydrogen the compound is an aldehyde.
Friedel crafts acylation is a very effective way of attaching a hydrocarbon based group to a benzene ring.