Featured research (2)
Polycyclic iridaaromatic compounds are of great interest not only because of the contributions made in "aromatic chemistry", but also because of the possibility of improving the results of the applications of the corresponding organic analogues in different fields. Therefore, understanding the requirements necessary to build on demand this type of compound with specific properties is of great importance. In this work, the keys to successfully synthesize iridaaromatic complexes via methoxyalkenylcarbenes are established. Experimental and theoretical results show (i) that bearing two aromatic substituents on the gamma carbon of the methoxyalkylcarbene promotes the C-H bond activation; (ii) the need for large steric hindrance of the second substituent for a selective synthesis and, (iii) the selectivity in the C-H bond activation towards the less sterically hindered system.
The selective synthesis of a spirobifluorene-iridacyclopentadiene complex has been achieved through the corresponding methoxyalkenylcarbeneiridium complex. The chemoselectivity of the C–H bond activation over the precursor has been studied via DFT calculations on the relative energies of the E and Z isomers of several examples and compared with experimental results. The data suggest that the steric effect of the substituents has more influence than their electronic character on the structure of the resulting iridacycle compounds.