Acylal

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The structure of a typical acylal. Acylal.PNG
The structure of a typical acylal.

Acylals in organic chemistry are a group of chemical compounds sharing a functional group with the general structure RCH(OOCR)2. Acylals are obtained by reaction of carbonyls with acetic anhydride or other acid anhydrides and a suitable catalyst, for instance with sulfated zirconia [1] at low temperatures when used as protective groups for aldehydes. High temperature exposure converts the acylal back to the aldehyde.

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References

  1. Negrón, Guillermo E.; Palacios, Laura N.; Angeles, Deyanira; Lomas, Leticia; Gaviño, Rubén (May–June 2005). "A mild and efficient method for the chemoselective synthesis of acylals from aromatic aldehydes and their deprotections catalyzed by sulfated zirconia" (PDF). J. Braz. Chem. Soc. São Paulo. 16 (3a): 490–494. doi: 10.1590/S0103-50532005000300025 .