Flow Heck reactions using extremely low loadings of phosphine-free palladium acetate.
High-yielding Heck reactions are demonstrated using 0.05 mol % Pd(OAc)2 without phosphine ligands. These reactions are run in a mesoscale flow reactor which allows precise control of reaction times and temperatures. Profiling yield and selectivity versus Pd loading shows 500 ppm to be optimal for aryl iodides; higher loadings favor side reactions caused by Pd(II) species. Aryl halides are examined via concise Design of Experiment to expand the scope and optimize conditions.
Worldwide Research and Development, Pfizer Inc., Eastern Point Road, Groton, Connecticut 06340, USA.
Patrick
P
Cyr
Stella T
ST
Deng
Joel M
JM
Hawkins
Kristin E
KE
Price
D000085:Acetates / Q000737:chemistry*; D002384:Catalysis; D006842:Hydrocarbons, Brominated / Q000737:chemistry*; D006847:Hydrocarbons, Iodinated / Q000737:chemistry*; D008024:Ligands; D015394:Molecular Structure; D010165:Palladium / Q000737:chemistry*; D013696:Temperature
D000085:Acetates; D006842:Hydrocarbons, Brominated; D006847:Hydrocarbons, Iodinated; D008024:Ligands; D010165:Palladium