Home > Community > Removing Pd(PPh3)4 from Reaction
Upvote

VOTE

Downvote
+ Organic
+ Chemistry
Posted by
Alec Cawley

Removing Pd(PPh3)4 from Reaction

Andrea Saez  Follow
I think you might be able to oxidize PPh3 to OPPh3 and precipitate it with ZnCl2 and then maybe chelate the palladium with EDTA and wash it away? I recall talking to a industry guy at a conference that mentioned having problems removing residual palladium after hydrogenation so they had to change the pathway completely but AFAIK he mentioned its possible to remove with edta.

More

Upvote

VOTE

Downvote
Curtis Evans  Follow
Why not chromatography?

More

Upvote

VOTE

Downvote
Angel Vasquez  Follow
maybe try to precipitate it by addition of a bad solvent for Pd(PPh3)4 to your hexane solution, make sure your compound is soluble obviously.

More

Upvote

VOTE

Downvote
Manjinder Nanrey  Follow
Quote from:
  I am trying to do a reaction on scale and a column is just not practical.

Thank you in advance!

Cheers!

@rolnor

More

Upvote

VOTE

Downvote
Brian Dean  Follow
@wildfyr

When you say let it convert to the oxide do you mean to atmospheric oxygen?

I have bought some TMT and it is on its way.  I am interested to see how well it works.  It seems it is used in industry as a Pd scavenger a lot.  I have also found that simple activated charcoal works to soak up some Pd, and then a simple Si plug works to purify the material to about 95% purity.

More

Upvote

VOTE

Downvote
Dog daycare/dog experts/cat experts  Follow
sorry, wash organics...im tired and didnt proof read...

Prost!

More

Upvote

VOTE

Downvote
Andi Quercia  Follow
Sorry, missed that!

More

Upvote

VOTE

Downvote
David Sandiford  Follow
The pph3 part can be removed by letting it convert to the oxide then using zinc chloride. It will make an adduct that can be filtered out.

More

Upvote

VOTE

Downvote
Ayaz Wasay  Follow
Yes, though I guess some weak inorganic (i.e. easily aqueous seperable) oxidizing agent could do it too.

My suggestion was to oxidize the PPh3 and complex that to the zinc to make an insoluble salt. I'm not sure what exactly to do with the Pd. Maybe if you can make it into some insoluble Pd salt like palladium oxide it can just be removed with celite filtration.

More

Upvote

VOTE

Downvote
Albert Donnay  Follow
Are you sure its the Pd(PPh3)4 complex?  In theory at least two PPh3 have to dissociate from the Pd in order for the reaction to proceed and I think you get other PdX2/4 species on workup, so you might just have the triphenylphosphine problem... which is in some ways worse.  I've heard PPh3 referred to as the herpes of reagents, and not without cause.

If it is tetrakis, you could probably oxidize the PPh3 and force the Pd to complex a less soluble ligand like wildfyr suggested.

Take it you don't want to run a column?

More

Upvote

VOTE

Downvote
Aiden Nalizda  Follow
I am trying to optimize the procedure.  It seems that a scavenger is maybe the best way to go.  Specifically TMT.  There is a polymer bound Pd scavenger made by biotage.

More

Upvote

VOTE

Downvote