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A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Electrophilic ipso-cyclization of N-(p-methoxyaryl)propiolamides involving an electrophile-exchange process
Bo-Xiao Tang1, Qin Yin, Ri-Yuan Tang
1Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research, Hunan Normal University, Changsha 410081, China.
Abstract:
A novel electrophilic ipso-cyclization involving an electrophile-exchange process has been developed. In the presence of CuX (X = I, Br, SCN) and electrophilic fluoride reagents, a variety of N-(p-methoxyaryl)propiolamides and 4-methoxyphenyl 3-phenylpropiolate were cyclized to selectively afford the corresponding spiro[4.5]decenones in moderate to good yields. It is noteworthy that two azaquaternary tricyclic products were synthesized through a two-step pathway involving an electrophilic ipso-cyclization and then an intramolecular Heck reaction.
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