Catalytic Dearomative Spirocyclization via Gold Carbene Species Derived from Ynamides: Efficient Synthesis of 2-Azaspiro[4.5]decan-3-ones

Mamoru Ito; Ryosuke Kawasaki; Kyalo Stephen Kanyiva; Takanori Shibata

doi:10.1002/chem.201800314

Catalytic Dearomative Spirocyclization via Gold Carbene Species Derived from Ynamides: Efficient Synthesis of 2-Azaspiro[4.5]decan-3-ones

Chemistry. 2018 Mar 12;24(15):3721-3724. doi: 10.1002/chem.201800314. Epub 2018 Feb 19.

Authors

Mamoru Ito¹, Ryosuke Kawasaki¹, Kyalo Stephen Kanyiva², Takanori Shibata^{1

3}

Affiliations

¹ Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University, Shinjuku, Tokyo, 169-8555, Japan.
² Global Center for Science and Engineering, School of Advanced Science and Engineering, Waseda University, Shinjuku, Tokyo, 169-8555, Japan.
³ ACT-C (Japan) Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama, 332-0012, Japan.

PMID: 29372752
DOI: 10.1002/chem.201800314

Abstract

An intramolecular catalytic dearomatization of phenols via gold carbene species proceeded to provide 2-azaspiro[4.5]decan-3-ones. The use of NHC ligand and water as a co-solvent was critical for achieving high reactivity. This reaction did not require hazardous diazo compounds as carbene sources and proceeded even under air. The obtained spirocyclic product could be readily transformed into a gabapentin derivative by hydrogenation and deprotection.

Keywords: carbenes; dearomatization; gold; spirocyclohexadienones; water.