GB1195909A - Process for the Production of Cycloacetal Esters and Cycloketal Esters - Google Patents

Abstract

1,195,909. Cycloacetal and cycloketal esters. CHEMISCHE WERKE HULS A.G. 30 Aug., 1967 [31 Aug., 1966], No. 39676/67. Addition to 1,166,636. Heading C2C. Cycloacetal and cycloketal esters of the formula wherein n is 1 or 2, k is 1-8, p is 0 or 1-8, m is 0 or 1-14, p + m being at least 1, R, R<SP>1</SP> and R<SP>2</SP> represent hydrogen or a hydrocarbon radical optionally substituted by groups which are inert under the reaction conditions, and R<SP>3</SP> represents a n-valent optionally substituted hydrocarbon radical or, when n is 2, a direct link, are prepared mixing together a triol of the formula a carbonyl compound R<SP>1</SP>.CO.R<SP>2</SP>, or a polymer thereof which yields the carbonyl compound under the reaction conditions, and an acid R<SP>3</SP>(CO 2 H)n, or the anhydride thereof, and allowing the reaction to proceed with continuous removal of water, an acid catalyst, different from the acid reactant and having a pKa of not more than 4, being present for at least the latter part of the reaction if the acid reactant has a pKa of more than 4. The reaction is preferably effected under reflux at 90-150‹ C. in the presence of a water-entrainer using stoichiometric proportions of reactants. Specified acidic catalysts include H 2 SO 4 , H 3 PO 4 , HClO 4 , BF 3 , AlCl 3 , SnCl 3 , cationic ion-exchange resins, acid-treated Montmorillonite, p-toluene sulphonic and trichloroacetic acids. The addition of a catalyst is not required if the acid reactant is, e.g. trichloroacetic, oxalic or formic acid. Examples relate to the preparation of esters of acetals and ketals derived from triols selected from trimethylolpropane, glycerol and 1,2,6-hexanetriol and carbonyl compounds selectedfromformaldehyde, cyclohexanone, propionaldehyde, iso - butyraldehyde and 2-ethylbutyraldehyde with acids selected from lauric, butyric, benzoic and 2-ethylbutyric acids.