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

Takayoshi Arai; Kodai Horigane; Ohji Watanabe; Junki Kakino; Noriyuki Sugiyama; Hiroki Makino; Yuto Kamei; Shinnosuke Yabe; Masahiro Yamanaka

doi:10.1016/j.isci.2019.01.029

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

iScience. 2019 Feb 22:12:280-292. doi: 10.1016/j.isci.2019.01.029. Epub 2019 Jan 23.

Authors

Takayoshi Arai¹, Kodai Horigane², Ohji Watanabe², Junki Kakino², Noriyuki Sugiyama², Hiroki Makino², Yuto Kamei³, Shinnosuke Yabe³, Masahiro Yamanaka⁴

Affiliations

¹ Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi, Inage, Chiba 263-8522, Japan; Soft Molecular Activation Research Center (SMARC), Chiba University, 1-33 Yayoi, Inage, Chiba 263-8522, Japan; Chiba Iodine Research Innovation Center (CIRIC), 1-33 Yayoi, Inage, Chiba 263-8522, Japan. Electronic address: tarai@faculty.chiba-u.jp.
² Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi, Inage, Chiba 263-8522, Japan.
³ Department of Chemistry, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima-ku, Tokyo 171-8588, Japan.
⁴ Department of Chemistry, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima-ku, Tokyo 171-8588, Japan; Research Center for Smart Molecules, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima-ku, Tokyo 171-8588, Japan. Electronic address: myamanak@rikkyo.ac.jp.

Abstract

Cooperative activation using halogen bonding and hydrogen bonding works in metal-catalyzed asymmetric halolactonization. The Zn₃(OAc)₄-3,3'-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. Halolactonization is significantly enhanced by the addition of catalytic I₂. Density functional theory calculations revealed that a catalytic amount of I₂ mediates the alkene portion of the substrates and NIS to realize highly enantioselective iodolactonization. The tri-Zn catalyst activates both sides of the carboxylic acid and alkene moiety, so that asymmetric five-membered iodolactonization of prochiral diallyl acetic acids proceeded to afford the chiral γ-butyrolactones. In the total description of the catalytic cycle, iodolactonization using the NIS-I₂ complex proceeds with the regeneration of I₂, which enables the catalytic use of I₂. The actual iodination reagent is I₂ and not NIS.

Keywords: Catalysis; Chemistry; Organic Synthesis; Stereochemistry.