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Updated: May 31, 2026

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Electrocyclization of phosphahexatrienes: an approach to λ5-phosphinines
Yurii V Svyaschenko1, Bogdan B Barnych, Dmitriy M Volochnyuk
1Institute of Organic Chemistry, National Academy of Sciences of Ukraine Murmanska 5, Kyiv-94, 02094, Ukraine.
Abstract:
We experimentally verified an assumption that the substitution of a carbon atom with a pentavalent phosphorus atom in 1-alkoxy (dialkylamino) hexatrienes will not hamper its ability to electrocyclize. A series of 1-, 3-, and 5-phosphahexatrienes were synthesized. It was shown that parent λ(5)-phosphinines could be synthesized by electrocyclization of the 3- and 5-phosphahexatrienes. The resultant electrocyclization is a convenient method for the synthesis of parent λ(5)-phosphinines bearing different substituents on the phosphorus atom.
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