Download PDF Opens in a new window. Article suggestions will be shown in a dialog on return to ScienceDirect. ... Please enable JavaScript to use all the features on this page. ... The reaction of 5-, 6- and 7-membered cyclic thioimidates with cyclopropenones gives access to highly functionalised pyrrolizidines, indolizidines and pyrroloazepines via a formal [3+2] cycloaddition process. ... Cyclopropenones react with cyclic thioimidates to give indolizidine and pyrrolizidine ...