In Friedel Crafts alkenylation, an alkyl halide + lewis acid + water + benzene ring is needed, however what would happen if it was just alkyl halide + lewis acid + water?

1 Answer
Jan 12, 2017

It wouldn't be a Friedel-Crafts reaction!

Explanation:

Friedel Craft alkylation (or acylation) is by definition an electrophilic aromatic substitution whereby an alkyl or acyl group is substituted for a hydrogen atom on an aromatic ring.

So if you simply take alkyl halide, Lewis acid and water you will not have any aromatic ring with which to react, and you will not have a Friedel Crafts reaction!

Its rather like saying "Sodium reacts with water to produce sodium hydroxide - what happens if I have just water?"