Solvent-Induced Reversal of Activities between Two Closely Related Heterogeneous Catalysts in the Aldol Reaction

Journal Article · Fri Jan 11 00:00:00 EST 2013 · ACS Catalysis

DOI:https://doi.org/10.1021/cs300748g· OSTI ID:1079977

Kandel, Kapil ^[1]; Althaus, Stacey M ^[1]; Peeraphatdit, Chorthip ^[1]; Kobayashi, Takeshi ^[1]; Trewyn, Brian G ^[1]; Pruski, Marek ^[1]; Slowing, Igor I ^[1]

---

1. Ames Laboratory

The relative rates of the aldol reaction catalyzed by supported primary and secondary amines can be inverted by 2 orders of magnitude, depending on the use of hexane or water as a solvent. Our analyses suggest that this dramatic shift in the catalytic behavior of the supported amines does not involve differences in reaction mechanism, but is caused by activation of imine to enamine equilibria and stabilization of iminium species. The effects of solvent polarity and acidity were found to be important to the performance of the catalytic reaction. This study highlights the critical role of solvent in multicomponent heterogeneous catalytic processes.

• Research Organization: Ames Lab., Ames, IA (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: DE-AC02-07CH11358
• OSTI ID: 1079977
• Report Number(s): IS-J 7922
• Journal Information: ACS Catalysis, Vol. 2013, Issue 3
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
mesoporous silica nanoparticles
aldol condensation
enamine catalysis
solvent effects
solid-state NMR