Download full text in 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. ... Addition of n,π* -excited thiocarbonyl compounds to ketene acetals leads to thietanes and/or . The results are discussed in terms of a mechanism involving intermediate 1,4-diradicals. ... Addition of n,π*-excited thiocarbonyl compounds to ketone acetals leads to thietanes ...