Castedo’s procedure,13 which uses a phase-transfer catalyst.
Racemic 1a has been prepared by an in situ (CF3-
COCH3)-catalyzed epoxidation of trans-â-methylstyrene
(H2O2 as primary oxidant at high pH), as reported by
Shi.14 (1S,2R)-(-)-1-Phenylpropylene oxide 1b has been
analogously synthesized (95% yield, ee g 95%) starting
from (1S,2S)-(+)-N-methylpseudoephedrine13 and racemic
1b by reduction of 1-phenyl-1-propyne,15 followed by
the oxidation of the resulting cis-â-methylstyrene according
to Shi’s procedure (62% overall yield).14