Direct Synthesis of a Nitrogen-Containing Eight-Membered Cyclic Alkyne from a Linear Alkyne and Its Reactivity
Tadachika Miyasaka1, Kenta Hishiki1, Masashi Yamaguchi1
1Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan.
None:
Eight-membered cyclic alkyne 3 was synthesized from 1, bearing an N-tosyl-o-alkynylanilide and alkyl bromide, by a high-temperature treatment in the presence of a base. This is the first example of the direct synthesis of an eight-membered cyclic alkyne containing a nitrogen atom from the corresponding linear alkyne. The structural requirements for this cyclization were also investigated. Eight-membered cyclic alkyne 3 reacted with benzyl azide without a copper(I) salt to give triazoles 17 and 18 at room temperature.
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