Efficient large-scale synthesis of 9-alkylfluorenyl phosphines for Pd-catalyzed cross-coupling reactions

CA Fleckenstein, R Kadyrov…

Index: Fleckenstein, Christoph A.; Kadyrov, Renat; Plenio, Herbert Organic Process Research and Development, 2008 , vol. 12, # 3 p. 475 - 479

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Citation Number: 15

Abstract

The reactions of aliphatic alcohols with fluorene coupled with a transfer hydrogenation result in the facile formation of 9-alkylfluorenes, whose deprotonation with n BuLi and quenching of the fluorenyl anion with Cy2PCl in MTBE gave 9-alkylfluorenyl-dicyclohexyl phosphines, which are conveniently isolated as the respective phosphonium tetrafluoroborates after treatment with aqueous HBF4. This route enables the facile large-scale (kilogram) ...