Intraparticle Diffusional Effects vs. Site Effects on Reaction Pathways in Liquid-Phase Cross Aldol Reactions

Koushik Ponnuru, Jinesh C Manayil, Hong Je Cho, Wei Fan, Karen Wilson, Friederike Jentoft

Research output: Contribution to journalArticle

Abstract

Chemo- and regioselectivity in a heterogeneously catalyzed cross aldol reaction were directed by tuning the nature of the sites, textural properties and reaction conditions. Catalysts included sulfonic-acid functionalized resins or SBA-15 with varying particle size or pore diameter, H-BEA zeolites, and Sn-BEA
zeotype; conditions were 25 °C to 170 °C in organic media. Benzaldehyde and 2-butanone yielded branched (reaction at -CH2- of butanone) and linear (reaction at -CH3) addition and condensation
products; and fission of the branched aldol led to β-methyl styrene and acetic acid. Strong acids promoted the dehydration step, and regioselectivity originated from preferred formation of the branched aldol. Both, resins and functionalized SBA-15 materials yielded predominantly the branched condensation product, unless particle morphology or temperature moved the reaction into the diffusion-limited regime, in which case more fission products were formed, corresponding to Wheeler Type II selectivity. For Hform zeolites, fission of the branched aldol competed with dehydration of the linear aldol, possibly because weaker acidity or steric restrictions prevented dehydration of the branched aldol.
Original languageEnglish
JournalChemPhysChem
Early online date7 Jan 2018
DOIs
Publication statusPublished - 7 Jan 2018

Bibliographical note

Copyright © 2018 by John Wiley & Sons. This is the peer reviewed version of the following article: Intraparticle Diffusional Effects vs. Site Effects on Reaction Pathways in Liquid-Phase Cross Aldol Reactions
Ponnuru, K., Manayil, J. C., Cho, H. J., Fan, W., Wilson, K. & Jentoft, F. 7 Jan 2018 In : ChemPhysChem., which has been published in final form at http://doi.org/10.1002/cphc.201701219. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.

Funding: NSF award 1560519. EPSRC (EP/K000616/2)

Keywords

  • acid-base catalysis
  • C-C bond cleavage
  • C-C coupling
  • Biomass Conversion

Fingerprint Dive into the research topics of 'Intraparticle Diffusional Effects vs. Site Effects on Reaction Pathways in Liquid-Phase Cross Aldol Reactions'. Together they form a unique fingerprint.

  • Cite this