Cycloaddition to C70 fullerene

The regioselectivity of the cydoaddition of N-methylazomethine ylide to C70 was daimed to be slightly affected using microwave irradiation as the source. By choosing an appropriate solvent (o-dichlorobenzene, ODCB) and the emitted microwave power, the ratio la lb is modified from 50 50 to 45 55 [26, 59] (Eq. (63) and Tab. 3.25). 

Theoretical calculations predict an asynchronous mechanism and suggest that the modification of the regiochemical outcome is related to the energies and hardness of the TS involved. Perhaps, in other words, the more polar TS are favored under the action of MW. 

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