Chiral analogs of polyethyleneimine based polymers were synthesized and crosslinked to yield homochiral scaffolds. The scaffold environment induced stereoselectivity in epoxidation reaction catalyzed by achiral catalysts. Thus, the homochiral scaffold was prepared by polymerization of the N-carboxy anhydride of the amino acid L-leucine initiated by 2-aminoacetonitrile and reduction with borane. Then, using an epichlorohydrin based crosslinker, an achiral manganese(III)salen catalyst was encapsulated within the homochiral polyethyleneimine polymer. This assembly exhibited asymmetric epoxidation of several styrene derivatives with low to moderate enantioselectivity in an aqueous biphasic reaction medium showing unique steric dependent effects.