1.2- Ethanediol cyclic acetals from

Outline all steps in the mechanism for the formation of a cyclic acetal from acetone and PRACTICE PROBLEM 16.11 ethylene glycol (1,2-ethanediol) in the presence of gaseous HCI. 

Diols that bear two hydroxyl groups m a 1 2 or 1 3 relationship to each other yield cyclic acetals on reaction with either aldehydes or ketones The five membered cyclic acetals derived from ethylene glycol (12 ethanediol) are the most commonly encoun tered examples Often the position of equilibrium is made more favorable by removing the water formed m the reaction by azeotropic distillation with benzene or toluene... 

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