Insertion Chemistry of Lutetacyclopropene toward Unsaturated C−O/C−N Bonds
Ze-Jie Lv, Wei Liu, Miaomiao Zhu, Zhengqi Chai, Junnian Wei, and Wen-Xiong Zhang*
Chem. Eur. J. 2021, https://doi.org/10.1002/chem.202103065
Although the reaction chemistry of transition metallacyclopropenes has been well-established in the last decades, the reactivity of rare-earth metallacyclopropenes remains elusive. Herein, we report the reaction of lutetacyclopropene toward a series of unsaturated molecules. The reaction of lutetacyclopropene with one equiv of PhCOMe, Ar1CHO (Ar1 = 2,6-Me2C6H3), W(CO)6, and PhCH=NPh provided oxalutetacyclopentenes, metallacyclic lutetoxycarbene, and azalutetacyclopentene via 1,2-insertion of C=O, C≡O, or C=N bonds into Lu−Csp2 bond, respectively. However, the reaction between lutetacyclopropene and Ar2N=C=NAr2 (Ar2 = 4-MeC6H4) gave an acyclic lutetium complex with a diamidinate ligand by the coupling of one molecule of lutetacyclopropene with two carbodiimides, irrespective of the amount of carbodiimide employed. More interestingly, when lutetacyclopropene was treated with two equiv of Ar1CHO, the reductive coupling of two C=O bonds was discovered to give a lutetium pinacolate complex along with the release of tolan. Remarkably, the reactivity of lutetacyclopropene is significantly different from that of scandacyclopropenes; these metallacycles derived from lutetacyclopropene all represent the first cases in rare-earth organometallic chemistry.
