Kinetic profiling has shown that a (DHQD)2PHAL-catalyzed
intermolecular asymmetric alkene bromoesterification reaction is inhibited
by primary amides, imides, hydantoins, and secondary cyclic amides,
which are byproducts of common stoichiometric bromenium ion sources.
Two approaches to resolving the inhibition are presented, enabling
the (DHQD)2PHAL loading to be dropped from 10 to 1 mol
% while maintaining high bromoester conversions in 8 h or less. Iterative
post-reaction recrystallizations enabled a homochiral bromonaphthoate
ester to be synthesized using only 1 mol % (DHQD)2PHAL.