Catalytic Asymmetric Iodoesterification of Simple Alkenes.

Catalytic asymmetric iodoesterification of simple alkenes was achieved using a dinuclear zinc-3,3'-(R,S,S)-bis(aminoimino)binaphthoxide (di-Zn) complex. For iodoesterification using p-methoxybenzoic acid, the N-iodonaphthalenimide (NIN)-I system was effective for producing iodoesters in a highly enantioselective manner. The synthetic utility of chiral iodo-p-methoxybenzoates was also demonstrated.

Association of Halogen Bonding and Hydrogen Bonding in Metal Acetate-Catalyzed Asymmetric Halolactonization.

Cooperative activation using halogen bonding and hydrogen bonding works in metal-catalyzed asymmetric halolactonization. The Zn(OAc)-3,3'-bis(aminoimino)binaphthoxide (tri-Zn) complex catalyzes both asymmetric iodolactonization and bromolactonization. Carboxylic acid substrates are converted to zinc carboxylates on the tri-Zn complex, and the N-halosuccinimide (N-bromosuccinimide [NBS] or N-iodosuccinimide [NIS]) is activated by hydrogen bonding with the diamine unit of chiral ligand.