Self- and Cross-Aldol Condensation of Propanal Catalyzed by Anion-Exchange Resins in Aqueous Media
Pyo, Sang-Hyun LU ; Hedström, Martin LU ; Lundmark, Stefan ; Rehnberg, Nicola LU
and Hatti-Kaul, Rajni
LU
(2011)
In Organic Process Research & Development
15(3).
p.631-637
- Abstract
- Carbon-carbon bond formation using strong and weak anion-exchange resins as green catalysts for self- and cross-aldol condensation of propanal in aqueous media was investigated. The reaction pathway followed the route of aldol condensation to a beta-hydroxy aldehyde and dehydration to an alpha,beta-unsaturated aldehyde. The resulting products were further converted to hemiacetal, and/or acetal moieties, which were confirmed by FT-IR and NMR. In self-condensation using strong anion-exchange resin, 97% conversion of propanal was achieved with 95% selectivity to 2-methyl-2-pentenal within 1 h using 0.4 g/mL resin at 35 degrees C. The conversion and selectivity using weak anion exchanger was lower. During cross-aldol condensation of propanal... (More)
- Carbon-carbon bond formation using strong and weak anion-exchange resins as green catalysts for self- and cross-aldol condensation of propanal in aqueous media was investigated. The reaction pathway followed the route of aldol condensation to a beta-hydroxy aldehyde and dehydration to an alpha,beta-unsaturated aldehyde. The resulting products were further converted to hemiacetal, and/or acetal moieties, which were confirmed by FT-IR and NMR. In self-condensation using strong anion-exchange resin, 97% conversion of propanal was achieved with 95% selectivity to 2-methyl-2-pentenal within 1 h using 0.4 g/mL resin at 35 degrees C. The conversion and selectivity using weak anion exchanger was lower. During cross-aldol condensation of propanal with formaldehyde, 3-hydroxy-2-methyl-2-hydroxymethylpropanal was obtained as the main product through first and second cross-condensation followed by hydration reaction in acidic aqueous conditions. The strong anion-exchange resin provided maximal propanal conversion of 80.4% to the product with 72.4% selectivity after 7 h reaction at 35 degrees C and resin concentration of 1.2 g/mL. Using weak anion-exchange resin, the optimal conversion of propanal was 89.9% after 24 h at 0.8 g/mL resin and 35 degrees C, and the main product was 3-hydroxy-2-methylpropanal by first cross-aldol condensation along with relatively minor amounts of methacrolein and 3-hydroxy-2-methyl-2-hydroxymethylpropanal. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1986286
- author
- Pyo, Sang-Hyun
LU
; Hedström, Martin
LU
; Lundmark, Stefan
; Rehnberg, Nicola
LU
and Hatti-Kaul, Rajni
LU
- organization
- publishing date
- 2011
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Organic Process Research & Development
- volume
- 15
- issue
- 3
- pages
- 631 - 637
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- wos:000290747700017
- scopus:79957529797
- ISSN
- 1083-6160
- DOI
- 10.1021/op200004p
- language
- English
- LU publication?
- yes
- id
- 46644aed-abdd-4060-ac3a-a27980f6d7f6 (old id 1986286)
- date added to LUP
- 2016-04-01 10:16:07
- date last changed
- 2022-03-19 19:08:19
@article{46644aed-abdd-4060-ac3a-a27980f6d7f6,
abstract = {{Carbon-carbon bond formation using strong and weak anion-exchange resins as green catalysts for self- and cross-aldol condensation of propanal in aqueous media was investigated. The reaction pathway followed the route of aldol condensation to a beta-hydroxy aldehyde and dehydration to an alpha,beta-unsaturated aldehyde. The resulting products were further converted to hemiacetal, and/or acetal moieties, which were confirmed by FT-IR and NMR. In self-condensation using strong anion-exchange resin, 97% conversion of propanal was achieved with 95% selectivity to 2-methyl-2-pentenal within 1 h using 0.4 g/mL resin at 35 degrees C. The conversion and selectivity using weak anion exchanger was lower. During cross-aldol condensation of propanal with formaldehyde, 3-hydroxy-2-methyl-2-hydroxymethylpropanal was obtained as the main product through first and second cross-condensation followed by hydration reaction in acidic aqueous conditions. The strong anion-exchange resin provided maximal propanal conversion of 80.4% to the product with 72.4% selectivity after 7 h reaction at 35 degrees C and resin concentration of 1.2 g/mL. Using weak anion-exchange resin, the optimal conversion of propanal was 89.9% after 24 h at 0.8 g/mL resin and 35 degrees C, and the main product was 3-hydroxy-2-methylpropanal by first cross-aldol condensation along with relatively minor amounts of methacrolein and 3-hydroxy-2-methyl-2-hydroxymethylpropanal.}},
author = {{Pyo, Sang-Hyun and Hedström, Martin and Lundmark, Stefan and Rehnberg, Nicola and Hatti-Kaul, Rajni}},
issn = {{1083-6160}},
language = {{eng}},
number = {{3}},
pages = {{631--637}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Organic Process Research & Development}},
title = {{Self- and Cross-Aldol Condensation of Propanal Catalyzed by Anion-Exchange Resins in Aqueous Media}},
url = {{http://dx.doi.org/10.1021/op200004p}},
doi = {{10.1021/op200004p}},
volume = {{15}},
year = {{2011}},
}