“…Several lead compounds and drug candidates have been developed incorporating this structural motif as illustrated with 2−7 (Scheme 1). 4−10 Considering the pharmaceutical significance of 1, a plethora of methods 11 have been developed for its synthesis but one obvious method, the cyclopropanation of 2,5-dihydropyrrole with ethyl diazoacetate (EDA), even though it has been explored by several groups, 4,6,8,10,12−16 still needs considerable improvement (Scheme 2A). The published procedures require 1−7 mol % rhodium acetate as catalyst, and the resulting yields range from 8 to 66%.…”