The Claisen-Schmidt Reaction Carried Out in Microfluidic Chips

Abstract

The Claisen-Schmidt reaction of benzaldehyde in a microfluidic chip has been found to be more efficient than that in a round-bottom flask with vigorous stirring. Slug flow was formed when the organic and aqueous phases were introduced through the microchannel with a width of 300 µm, which provides faster mass transfer than laminar flow.

Key words

microfluidic chips - phase-transfer catalysts - Claisen-Schmidt reaction - benzaldehyde - acetone

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6

General Procedure.
Benzaldehyde (1 mmol), acetone (4 mmol), EtOH (1.0 mL) and aqueous NaOH (0.5 M, 1.0 mL) were placed in a 10-mL round-bottomed flask and stirred at ambient temperature under a N₂ atmosphere. After stirring for period indicated in Figure [2] , the reaction was quenched with HCl (0.5 M, 1 mL). The organic layer was separated and the aqueous layer was extracted with Et₂O (3 × 2 mL). The combined organic layers were washed with H₂O (5 mL) and dried with Na₂SO₄. The solvent was removed to give benzylidineacetone. The conversion of each period is cited in Figure [2] .