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Updated: Apr 10, 2026

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
Alternative Synthesis and Structures of C-monoacetylenic Phosphaalkenes
Andreas Orthaber1, Elisabet Öberg1, Reuben T Jane1
1Department of Chemistry-Ångström Laboratory, Uppsala University Box 523, SE-751 20, Uppsala, Sweden.
Abstract:
An alternative synthesis of C-monoacetylenic phosphaalkenes trans-Mes*P=C(Me)(C≡CR) (Mes* = 2, 4, 6-tBu3Ph, R = Ph, SiMe3) from C-bromophosphaalkenes cis-Mes*P=C(Me)Br using standard Sonogashira coupling conditions is described. Crystallographic studies confirm cis-trans isomerization of the P=C double bond during Pd-catalyzed cross coupling, leading exclusively to trans-acetylenic phosphaalkenes. Crystallographic studies of all synthesized compounds reveal the extend of π-conjugation over the acetylene and P=C π-systems.
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