Here again, as in the case of lithiation of styrene oxide, the presence of
TMEDA and of a donor solvent (THF) was unavoidable;
in fact, the use of a nondonor solvent (hexane), the
absence of TMEDA, and a higher temperature (>-98 °C)
exalted the carbenoid nature of 2a, thus leading to the
formation of enediols 4 (“eliminative dimerization”)18 and
alkenes 5 which are the result of a “reductive alkylation”
process promoted by s-BuLi on 2a with concomitant
elimination of Li2O (