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Updated: Jun 29, 2025

Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes
Published on: September 8, 2013
Synthesis of Alkenylgold(I) Complexes Relevant to Catalytic Carboxylative Cyclization of Unsaturated Amines and
Shun Hase1, Kyohei Yamashita1, Yoshihito Kayaki1
1Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, 2-12-1-E4-1 O-okayama, Meguro-ku, Tokyo 152-8552, Japan.
Abstract:
The carboxylation of unsaturated amine and alcohol compounds, including 4-benzylamino-1-phenyl-1-butyne (homopropargylamine), 2-butyne-1-ol (propargylic alcohol), and 2,3-butadiene-1-ol (allenylmethyl alcohol), using the hydroxidogold(I) complex, AuOH(IPr) [IPr = 1,3-bis(2,6-diisopropylphenyl)-imidazol-2-ylidene], produces corresponding alkenylgold(I) complexes with a cyclic urethane or carbonate framework in high yields. The reaction takes place in aprotic THF at room temperature under the atmospheric pressure of CO2 in the absence of base additives. The products were characterized by NMR spectroscopy, elemental analysis, and X-ray crystallography. The functionalized alkenyl complexes prepared from the alkynes can be protonated by treatment with an equimolar amount of acetic acid to afford five- or six-membered carboxylation products, whereas the related alkenyl complex derived from allenylmethyl alcohol decomposed to recover the starting allene via ring-opening decarboxylation.
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