Title
Introduction
Other Methods
Precedents
Why we were doing this chemistry
Known Methodology
Discovery
Mechanism
Summary of Results

The desired starting endoxide was readily available via standard aryne (1,2) chemistry pioneered by Wittig (3). Previous attempts by others in our laboratory failed to give the high yields of endoxides reported.

We guessed that our magnesium might not be fresh enough to form the Grignard reagent, and since we were not set up to sublime the metal, we tried adding more Mg to the reaction pot in an effort to increase the yield. However, doing so lowered the yields of the endoxide even further!

Endoxides produced in this fashion are easily purified by distillation and high vacuum oven drying of the resultant solid. The volatility of starting materials made it seem likely that we simply weren't getting formation of the Grignard reagent, but were simply losing the starting materials through evaporation.

(1) Newman, M. S.; Dali, H. M.; Hung, W. M. J. Org. Chem. 1975, 40, 262; (2) Wolthius, E. J. Org., Chem. 1961, 2215; (3) Wittig, G.; Pohmer, L. Ber. 1956, 89, 1334.