Untersuchungen über ätherartige Verbindungen, III. Mitteil.: Zur Kenntnis der cyclischen Ketale acyclischer Ketone

The Use, for Condensation Reactions, of Potassium Hydroxide in Solvents of the Acetal Type

“…The preparation of cyclic acetals by azeotropic condensation has been described in a previous communication (34); the method is not applicable to the lowest-boiling representatives of the aliphatic ketones. It was, however, observed that the preparation of 2-methyl -2-ethyldioxolane from methyl ethyl ketone and ethylene glycol was much easier than literature data (35,36,37) would have led one to suspect. A mixture of 124 g. of glycol, 1152 g. of methyl ethyl ketone, 11.5 g. of gaseous hydrochloric acid, and 25 g. of anhydrous mag- " Procedure: To 0.25 mole of KOH (16.5 g. of technical potassium hydroxide) in the acetal was added a mixture of the hydrocarbon and the carbonyl compound at 20°.…”

Synthèses de dioxolannes α-iodés

“…Elle fait appel a la synthkse de cttones a-iodees par Cchange iode-chlore ou iode-brome au moyen de l'iodure de potassium B partir de cttones a-chlorkes ou a-bromtes (5, 6) suivie de leur cttalisation (7).…”

“…Les cCtones iodtes correspondantes, obtenues selon le mode operatoire de Modara'i et Khosdel ( 3 , sont traitCes suivant le mCthode de Salmi (7).…”

“…Synrhise de cBtals a-iodts selon la 3' mtthode Les dioxolannes des cCtones ont Ct C preparks selon Salmi (7). La reaction d'iodation est conduite sous azote avec agitation magnktique.…”