Asymmetric methoxyselenenylation of alkenes with chiral ferrocenylselenium reagents

Asymmetric methoxyselenenylation of alkenes was studied using some chiral ferrocenylselenium compounds which were prepared from chiral ferrocenyl-substituted amine, sulfoxide, oxazoline, and pyrrolidine. The highest diastereoselectivity was observed using the chiral amino-substituted ferrocenylserenium triflates in the reaction with trans-beta-methylstyrene in an excellent yield. The reaction with silyl enol ethers gave chiral alpha-seleno ketone with moderate to excellent selectivities. The beta,gamma-unsaturated ester may be converted into the optically active gamma-alkoxy alpha,beta-unsaturated ester using ammonium persulfate in the presence of a catalytic amount of the chiral diferrocenyl diselenide in low optical yields.