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. ... A unique solvent effect encountered in the Barton–Zard pyrrole synthesis was exploited to develop an efficient synthesis of pyrrole-2-esters. The chemistry was extended to a one-pot synthesis of pyrrole-2,4-dicarboxylates. ... A unique solvent effect encountered in the Barton–Zard ...