Asymmetric Epoxidation by H₂O₂ with Resin-Supported Peptide

Significance

An amphiphilic resin-supported peptide (1) catalyzed the enantio- and diastereoselective epoxidation of α,β-unsaturated aldehydes 2 with hydrogen peroxide followed by reduction with NaBH₄ to give the corresponding epoxides 3 in 45-83% isolated yield with trans/cis ratios of 95:5 to 98:2 and 74-91% ee (7 examples, eq. 1). In the formation of 3a the catalyst was recovered by simple filtration and reused twice without significant loss of its catalytic performance (1^st reuse: 87% yield, trans/cis = 98:2, 95% ee; 2^nd reuse: 72% yield, trans/cis = 96:4, 95% ee).