Sciencemadness Discussion Board

Phenyllithium attemt

fastbre4k - 2-1-2017 at 08:52

Hey,

i tried to preparate Phenyllithium.

in 150ml of Chlorobenzene was added 2g of lithium (fine strips)(from battaries) - then i started a reflux. Within 5 minutes i noticed a color change from , first light green and then going into dark yellow.

I guess that : https://en.wikipedia.org/wiki/Aryne

PirateDocBrown - 2-1-2017 at 10:31

You dropped the Li directly into the PhCl?

Next time, try a solvent. Dry Et2O or THF, for example.

Sparge your reactant/solvent with inert gas before adding the metal, and exclude atmospheric O2 from the reaction.

You will get better results with PhBr.

Also, a catalytic amount of Na metal has always helped me a bit.

fastbre4k - 2-1-2017 at 11:03

Jea - directly

mhm - next time with solvent - i guess xylene would work?

inert gas i have - N2




draculic acid69 - 24-9-2018 at 05:25

So how did it go with xylene?

S.C. Wack - 24-9-2018 at 13:46

Not well I bet.

It's not an oversight that the directions (edit: e.g. OS CV2 page 517) say bromobenzene and ether (preferably with a bit of sodium) and don't say feel free to substitute with chlorobenzene and xylene.

[Edited on 24-9-2018 by S.C. Wack]

JJay - 24-9-2018 at 14:15

Phenyllithium will react with xylene, exchanging a benzylic hydrogen per methyl group for lithium. It will also react with toluene.