ORGN 149 |
| The development of new reaction conditions for the Suzuki-Miryaura coupling reaction has been an expanding area of research over the past several years. The goal in many of these new reaction conditions has been to improve overall yield, reduce reaction time, and provide less harsh reaction conditions along with many other goals. The motivation of this research is to demonstrate the utility of neopentylphosphine ligands as alternatives to tri-tert-butylphosphine. Previous efforts suggest that increasing the steric and electronic effects of the phosphine ligand leads to an increase in the reactivity of the phosphine palladium catalyst. This increase in reactivity results in lower catalyst loading and higher turnover frequency of the catalyst, thereby providing a reduction in reaction time. Additionally, an increase in reactivity should afford means for the coupling of more difficult substrates that previously have proven challenging. Both di-tert-butylneopentylphosphine (DTBNpP) and tert-butyldineopentylphosphine (TBDNpP) have been investigated and shown to give isolated yields between 84-95%, which are comparable to tri-tert-butylphosphine. Future work will involve the expansion to trineopentylphosphine (TNpP) and di-tert-butyl(3-methoxy-2,2,-dimethylpropyl)phoshpine (DTBOMe). |
|
Process R&D, Physical Organic Chemistry, Heterocycles, Aromatics, Metal-Mediated Reactions
8:00 PM-10:00 PM, Sunday, March 25, 2007 Hyatt Regency Chicago -- Riverside Center, Poster
Division of Organic Chemistry |