An aldol condensation using ethanal and benzaldehyde also works if you add your ethanal into a refluxing mixture of benzaldehyde and sodium hydroxide solution. Although, cis/trans (E/Z) isomer mixtures are possible, the trans predominates as it is formed much more quickly. The yield, is not quite the 80%+ expected of most modern lab preparations, but the starting materials are cheap and the procedure is simple.

It will depend on your starting compound. Which initial substances do you means?

http://pubs.acs.org/doi/abs/10.1021/ja01594a065

Claude J. Schmidle , Patricia G. Barnett

J. Am. Chem. Soc., 1956, 78 (13), pp 3209–3210

Cinnamaldehyde is prepared in one step by the oxidation of cinnamyl alcohol using PCC [pyridinium chlorochromate (C5H5NH+ CrO3Cl-)] as the oxidizing agent in DCM (dichloromethane). The reaction system is subjected to reflux & stirring (using a magnetic bar) for about 20 minutes. The reaction is selective , i.e. the double bond is nearly not affected & it will not undergo further oxidation towards the carboxylic acid.

Convenient preparations of the desired aldehyde from the corresponding alcohol are described in the following references:

L-Proline: an efficient N,O-bidentate ligand for copper-catalyzed aerobic oxidation of primary and secondary benzylic alcohols at room temperature

Chem. Commun., 2013,49, 7908-7910

Efficient oxidation of arylmethylene compounds using nano-MnO2

Tetrahedron Letters

Volume 54, Issue 15, 10 April 2013, Pages 2010–2013

An aldol condensation using ethanal and benzaldehyde also works if you add your ethanal into a refluxing mixture of benzaldehyde and sodium hydroxide solution. Although, cis/trans (E/Z) isomer mixtures are possible, the trans predominates as it is formed much more quickly. The yield, is not quite the 80%+ expected of most modern lab preparations, but the starting materials are cheap and the procedure is simple.

starding material is benzaldehyde

An addition to method provided by Paul Carolan: u can use DBU instead NaOH. Yields are around 70%

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