Diastereoselective Giese addition on coumarin-3-carboxylate bearing a chiral auxiliary
with N-hydroxyphthalimide ester to generate the corresponding alkylated adduct has been
explored. Among screened chiral auxiliaries, bulkier one with appropriate steric hindrance
is better for diastereoselective addition. Mechanistic studies involving fluorescence
studies and On/Off experiments shed insight onto the plausible reaction pathway.
Key words
diastereoselectivity - coumarin-3-carboxylate - (+)-phenylmenthol -
N-hydroxyphthalimide ester - Eosin Y