Spiro-cyclic ketal cpds., prepn. from decalone and diol - and use as heat transfer medium, dielectric liq. or photographic emulsion mfr.

摘要

New spirocyclic ketals have formula (I) and are derived from 1-decalone (II). R1-7 independently are H, 1-4C alkyl, 1-4C alkoxy or a 5-7C cycloaliphatic gp. Z is a 2-4C alkylene gp., opt. substd. by 1-4C alkyl gps. or a satd. carbocyclic ring. If R1-7 are H, Z is not an ethylene gp. Pref. Z is -CH2-CHM4-, -(CH2)3- or -CH2CMe2-CH2-. (I) are prepd. by reacting (II) with diols (III) of the formula HO-Z-OH, (III) pref. being propane-1,2- or 1,3-diol or 2,2- dimethyl-propane-1,3-diol. It is pref. to use an equimolar mixt. of (III) and a lower alkyl orthocarboxylate for ketalisation. (I) are specified for use as heat transfer media, dielectric liqs. or for the mfr. of photographic emulsions.