Abstract: A process for the preparation of 3-hydroxyoxetanes of formula I ##STR1## wherein R.sub.9 and R.sub.10 are each independently of the other hydrogen or C.sub.1 -C.sub.4 alkyl, by(1) reaction of a carboxylic acid R--CO.sub.2 H, wherein R is branched alkyl, with an epichlorohydrin of formula II ##STR2## wherein R.sub.9 and R.sub.10 are as defined hereinbefore, to form an ester of formula III ##STR3## wherein R, R.sub.9 and R.sub.10 are as defined hereinbefore, (2) reaction of that ester with an ether of formula IVCHR.sub.1 .dbd.CH--O--R.sub.2 (IV),wherein R.sub.1 is hydrogen or methyl, R.sub.2 is C.sub.1 -C.sub.6 alkyl, or R.sub.1 and R.sub.2 together form a radical of formula --(CH.sub.2).sub.3 --, in the presence of a catalyst, to form an ester of formula V ##STR4## (3) hydrolysis and cyclization of that ester in the presence of a base to form a compound of formula VI ##STR5## wherein R.sub.1, R.sub.2, R.sub.9 and R.sub.