Converting homogeneous to heterogeneous in electrophilic catalysis using monodisperse metal nanoparticles.
A continuing goal in catalysis is to unite the advantages of homogeneous and heterogeneous catalytic processes. To this end, nanoparticles represent a new frontier in heterogeneous catalysis, where this unification can also be supplemented by the ability to obtain new or divergent reactivity and selectivity. We report a novel method for applying heterogeneous catalysts to known homogeneous catalytic reactions through the design and synthesis of electrophilic platinum nanoparticles. These nanoparticles are selectively oxidized by the hypervalent iodine species PhICl(2), and catalyse a range of π-bond activation reactions previously only catalysed through homogeneous processes. Multiple experimental methods are used to unambiguously verify the heterogeneity of the catalytic process. The discovery of treatments for nanoparticles that induce the desired homogeneous catalytic activity should lead to the further development of reactions previously inaccessible in heterogeneous catalysis. Furthermore, a size and capping agent study revealed that Pt PAMAM dendrimer-capped nanoparticles demonstrate superior activity and recyclability compared with larger, polymer-capped analogues.
Department of Chemistry, University of California, Berkeley, California 94720, USA.
Cole A
CA
Witham
Wenyu
W
Huang
Chia-Kuang
CK
Tsung
John N
JN
Kuhn
Gabor A
GA
Somorjai
F Dean
FD
Toste
D002384:Catalysis; D003500:Cyclization; D050091:Dendrimers / Q000737:chemistry; D007455:Iodine / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry*; D010084:Oxidation-Reduction; D010165:Palladium / Q000737:chemistry; D010671:Phenylurea Compounds / Q000138:chemical synthesis / Q000737:chemistry; D010984:Platinum / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry
D050091:Dendrimers; C104700:PAMAM Starburst; D010671:Phenylurea Compounds; C509969:SBA-15; D010984:Platinum; D010165:Palladium; D012822:Silicon Dioxide; D007455:Iodine