Multiply exo-Methylated Corannulenes

The curved & pi;-conjugated surface of bowl-shaped corannulene has been multiply methylated to form exo-di-, -tetra-, and -hexamethylated corannulenes. The multimethylations became possible through in-situ iterative reduction/methylation sequences that involve the reduction of corannulenes using sodium to form the anionic corannulene species, and the subsequent S(N)2 reaction of the anionic species with reduction-resistant dimethyl sulfate. X-ray diffraction analyses, NMR, MS, UV-Vis measurements, and DFT calculations have revealed the molecular structures of the multimethylated corannulenes and the sequence of the multimethylation. This work has the potential to contribute to the controlled synthesis and characterizations of multifunctionalized fullerenes.

Automated summary

The curved and π-conjugated surface of bowl-shaped corannulene has been multiply methylated through in-situ iterative reduction/methylation sequences, resulting in exo-di-, -tetra-, and -hexamethylated corannulenes. Various analytical techniques have been used to reveal the molecular structures of the multimethylated corannulenes and the sequence of the multimethylation. This work has the potential to contribute to the controlled synthesis and characterization of multifunctionalized fullerenes.