Online article for Non-subscribers

Pay per view

Heterocycles has a pay-per-view service for Non-subscribers.
You will be able to directly purchase the full text article through PayPal.
Your purchased Paper can be downloaded after the payment is completed.
An e-mail will be sent the URL to download the paper.
If you have any questions, please contact:

Price: ¥ 4,400 (Yen only)
Period: This Article can be accessed for 7 days.

Short Paper | Special issue | Vol 95, No. 1, 2017, pp.525-539
Published online, 5th August, 2016
DOI: 10.3987/COM-16-S(S)12
Synthesis of γ-Trifluoromethyl Tetronate Derivatives from Squarates

Yoshihiko Yamamoto,* Yosuke Takamizu, Takashi Kurohara, and Masatoshi Shibuya

*Department of Basic Medicinal Sciences, Graduate School of Pharmaceutical Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601, Japan


Squarates and semisquarates were treated with TMSCF3 in the presence of a catalytic amount of AcONa in DMF at room temperature to afford 4-trifluoromethyl-4-hydroxycyclobutenones. Subsequent oxidative ring expansion of these products was performed using Pb(OAc)4 in the presence of MS 4A in 1,2-dichloroethane at 50 °C to afford γ-trifluoromethyl tetronate derivatives.