2,6-Dioxa-bicyclo-[2,2,2]-octane-7-yl-acetaldehydes of the general Formula I, ##STR1## wherein R.sub.1 is a benzyl or lower alkyl group, and A and B either are each hydrogen or together represent a single bond between their respective carbons, and a method for producing such compounds. The compounds are valuable intermediates in the synthesis of pharmacologically active substances having, for example, cardiovascular effects.