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Updated: Jan 6, 2026
Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
Phosphahelicenes with (Thio)Phosphinic Acid and Ester Functions by the Oxidative Photocyclisation Approach
Julie Febvay1, Charles S Demmer1, Pascal Retailleau1
1Institut de Chimie des Substances Naturelles, CNRS UPR 2301, Université Paris-Sud, Université Paris-Saclay, 1, av. de la Terrasse, 91198, Gif-sur-Yvette, France.
Abstract:
Phosphahelicenes with thiophosphinic acid and ester functions have been obtained by the oxidative photocyclisation of olefins bearing both a benzophenanthrene and a benzophosphole unit. When the method has been extended to olefins bearing a partially saturated benzophospholene unit, a divergent regioselectivity of the photocyclisation step has been observed, leading to new helicenes in which the phosphorus function is located on the external rim of the helical backbone. The observed regioselectivity correlates well with the free-valence numbers of the atoms involved in the photocyclisation reaction (DFT calculations).
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