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Chemistry Forums for Students => Organic Chemistry Forum => Organic Chemistry Forum for Graduate Students and Professionals => Topic started by: raohonghua on June 01, 2006, 05:55:47 AM

Title: Suzuki Reactions
Post by: raohonghua on June 01, 2006, 05:55:47 AM
When I am carrying the suzuki reactions using NiCl2-6H2O as the catalyst and Bpy as the ligand, however, I did not get the product but the homocoupling of Ar-B(OH)2. Would you please tell me what is the problem? Thank you very much! By the way, I am a freshman at this forum.
Title: Re: Suzuki Reactions
Post by: Dan on June 01, 2006, 09:28:50 AM
Is there any specific reason you are using a Ni catalyst? I was under the impression that Pd(PPh3)4 is the standard catalyst for Suzuki coupling (generated in situ from Pd(II) acetate). I have sucessfully carried out a Suzuki coupling in this way.
Title: Re: Suzuki Reactions
Post by: Will on June 01, 2006, 09:45:32 AM
Quote from: Dan on June 01, 2006, 09:28:50 AM
I was under the impression that Pd(Ph3)4 is the standard catalyst for Suzuki coupling (generated in situ from Pd(II) acetate). I have sucessfully carried out a Suzuki coupling in this way.

Do you mean Pd(PPh3)4? :)
Title: Re: Suzuki Reactions
Post by: Dan on June 01, 2006, 09:50:23 AM
Yes I do! Not the horrific complex I suggested - I have corrected it.
Title: Re: Suzuki Reactions
Post by: ethylacetate on June 17, 2006, 04:11:08 AM
???????
Title: Re: Suzuki Reactions
Post by: heyjude22 on June 30, 2006, 05:40:29 PM
I would suggest using Pd(PPh3)4 for a Suzuki coupling.  In my experience, it has always worked pretty well.  Another thing to consider is changing the base you use.  This can facilitate the transmetallation step and increase the rate of reaction.
Title: Re: Suzuki Reactions
Post by: PRIYA1022 on July 11, 2006, 08:40:39 PM
 Suzuki reactions are also carried out with Nickel in place of palladium. I would suggest a ligand change. Try this reference..J. Org. Chem., Vol. 62, No. 23, 1997.page 8024 and J. Org. Chem. 1996, 60,pages 1060.
Title: Re: Suzuki Reactions
Post by: CDW101057 on November 15, 2006, 10:53:46 PM
The following condition: tris(dibenzylideneacetone)dipalladium(0), tri-tert-butylphosphine and anyhydryous cerium cabonate might be a better choice. ;D
Title: Re: Suzuki Reactions
Post by: movies on November 18, 2006, 01:41:18 PM
Those conditions work best under conditions where you can get beta-hydride elimination.  The tetrakis conditions are a lot more convenient and cheaper though!