I have looked up the current definitions for the term in the Hyperglossary,
and IHMO Achim's definition (Acetal) is the correct one. It is characteristic
for an acetal that there is still one H-atom bound to the central C-atom
compared to the definition of ketals where the central C-atom is bound to two
other C-atoms (just as in ketones).
In addition even though IUPAC still allows the usage of the term 'ketal' it
is common to use the term 'acetal' for both.
Christian
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Christian Frosch frosch@mzdmza.zdv.uni-mainz.de
Biomoo: Kermit http://www.uni-mainz.de/~frosc000
Phe group home page http://www.uni-mainz.de/~frosc000/phe.html
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