[UrbanLegend]

Anyone got any idea what to substituted the TMEDA (ligand for metal ions)? Thank for reading and reply....

Preparation of 1-phenylhexane and 2-phenylbutane

Reaction:
Bromobenzene + 2-bromobutane --(FeCl3/THF)/(Mg, TMEDA)- > 2-phenylbutane

[Note: Glassware must be dried at 110oC the lab period before step is performed since Mg reacts violently with water. Glassware used in this reaction will be purged with Nitrogen gas; set up is lengthy and everything must be ready as soon as lab period begins.]
[Note: TMEDA used as additive to stabilize the iron complexes formed during course of reaction and reduce b-hydride elimination and homocoupling side reactions or TMEDA acts as a ligand for the catalyst species and magnesium.]

Substitute: TMEDA ligand    --- >   ethylenediamine ligand (any more???)

Procedure:
Place 240mg of Mg power in a 3-sidearm flask, followed by 16.2mg of FeCl3 in 15 mL of the THF. Purge flask with Nitrogen gas and fit with two rubber stoppers and a cork stopper. Add 0.6mL of TMEDA via syringe and stir for 20 minutes. After 20 minutes of stirring, cool down to 0oC and add 0.4mL of bromobenzene and 0.5mL of 2-bromobutane. Stir mixture for 30 minutes and quench with 5mL of saturated NH4Cl in 10% HCl. Extract solution with 3x 10mL of ethyl acetate, dry over MgSO4 and evaporate solvent using a rotovap. Analyzed product obtained using GCMS, IR and NMR.

Follow same procedure using bromohexane from stock instead of 2-bromobutane.

[Doc Oc]

Maybe another bidentate amine like DABCO would work?

[UrbanLegend]

Is TMEDA a based or acid in this procedure?

[Doc Oc]

Neither.  From what I can tell it's a chelating agent, it prevents undesirable side reactions from occurring.  Other tertiary diamines could work, that's why I suggested DABCO.  If you're looking for something besides that I can't think of anything off-hand, but maybe someone with more experience in this coupling can speak up.