Oglialoro modification, Perkin reaction

Here the phenylacetic anhydride, possessing more reactive a-hydrogen atoms, oondenses with benzaldehyde to give a-phenylcinnamic acid. The preparation of the latter is an example of the Oglialoro modification of the Perkin reaction. 

Although acetic anhydride is often used in the Perkin reaction as the acid anhydride component, other acid anhydrides can be used in the Perkin reaction as well. Oglialoro reported that sodium phenylacetate 21 and acetic anhydride give a-phenylcinnamic acid 22. The Oglialoro modification generates a mixed anhydride in situ and is a convenient preparative method that obviates the necessity of using the arylacetic anhydride as a starting material.2... 

The most important modification of the Perkin reaction was developed by Oglialoro using the sodium salt of acetic acid (e.g., phenylacetic acid, phenoxyacetic acid ) in condensation with acetic anhydride and an aldehyde (e.g., benzaldehyde, paraldehyde ). This type of reaction is referred to as the Perkin-Oglialoro reaction,Perkin-Oglialoro condensation, or Oglialoro modification. Other modifications include the use of different bases as the catalysts, (e.g., NaB(OMe)4-LiCl, CaH2, CsOAc, and CsF ), the use of microwave irradiation and cesium acetate or fluoride in combination with a small amount of pyridine as catalyst and the continuous distillation of acetic acid to enhance the conversion rate. ... 

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