Aldol condensation allows the formation of C-C bonds.
It is commonly used to manufacture solvents (diacetone alcohol and isophorone),
intermediates for the manufacture of perfumes and pharmaceuticals (chalcones
and more generally a,b unsaturated ketones) and plasticizers. The aldolization
can be catalyzed by acids or bases, but base catalysis is usually preferred.
Aldolization of acetone
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Examples
• Condensation
of acetone to diacetone alcohol can be readily catalyzed by various
weak base (Amberlyst™ A21) and strong base (Amberlyst™
A26) polymeric catalysts.
• The aldol
condensation of citral with acetone at 55°C under a strong base
gel resin catalyst (Amberlite™ IRA400) in replacement of sodium
hydroxide has been studied. 90-95% conversion was obtained with
5-10% unreacted citral. The resulting product is pseudoionone which
is a commercial intermediate for the production of flavours like
alpha and beta ionones and also for the synthetic production of
vitamins.
• A. Kinetic
study of the aldol condensation of n-butyraldehyde with formaldehyde
over a weak bas gel resin catalyst has been studied bySerra-Holm.
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Weak base macroporous polystyrene based catalyst.
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Type 1, strong base macroporous polystyrene based catalyst.
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Amberjet™ 4400 OH |
Type 1, strong base gel type. |
For sampling, pricing and availability of AMBERLYSTT
catalysts please contact your Rohm and
Haas sales representative.
- V. Serra-Holm, T. Salmi, J.
Multamäki, J. Reinik, P. Mäki-Arvela, R. Sjöholm,
L.P. Lindfors "Aldolization of butyraldehyde with formaldehyde
over a commercial anion-exchange resin -kinetics and selectivity
aspects" Applied Catalysis A: General 198 (2000) 207-221.
- G.G. Podrebarac, F.T.T. Ng,
G.L. Rempel "A kinetic study of the aldol condensation of
acetone using an anion exchange resin catalyst", Chemical
engineering Science, vol 52, N° 17, pp 2991-3002 (1997).
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