(CYCLOBUTADIENE)TRICARBONYLIRON COMPLEXES - FORMATION OF 1,3-SUBSTITUTED AND 1,2,3-SUBSTITUTED DERIVATIVES

Current methods available to modify or append alkyl groups to (cyclobutadiene)tricarbonyliron limit its use and study. Using selective alkylations and rearrangements on diisopropyl squarate, we have developed simple and efficient routes to specific 1,3-disubstituted (2) and 1,2,3-trisubstituted (3) (cyclobutadiene)tricarbonyliron complexes. These methods represent the first direct syntheses of these complexes and provide new entries into potentially novel cyclobutadiene-derived synthons and complexes.