Collect. Czech. Chem. Commun. 2002, 67, 1345-1358

Synthesis of (Polyfluoroalkyl)cyclopentenes as Model Compounds for Fluorophilic Cyclopentadienes

Jaroslav Kvíčalaa,*, Tomáš Břízaa, Oldřich Paletaa and Jan Čermákb

a Department of Organic Chemistry, Institute of Chemical Technology Prague, Technická 5, 166 28 Prague 6, Czech Republic
b Institute of Chemical Process Fundamentals, Academy of Sciences of the Czech Republic, Rozvojová 135, 165 02 Prague 6, Czech Republic


Nucleophilic opening of the epoxide ring in 6-oxabicyclo[3.1.0]hexane (1) with ethenylmagnesium bromide was employed for the preparation of 2-ethenylcyclopentan-1-ol (2). Radical addition of perfluoroalkyl iodides 3 to alcohol 2 afforded (polyfluoroiodoalkyl)cyclopentanols 4, which were deiodinated with tributylstannane to (polyfluoroalkyl)cyclopentanols 5, followed by dehydration with Nafion-H to the target (polyfluoroalkyl)cyclopentenes 6, which are potential intermediates for fluorous chemistry. Attempts to synthesize (polyfluoroalkyl)cyclopentadienes or bis(polyfluoroalkyl)cyclopentadienes failed due to the exclusive formation of unexpected side product, polyfluoroiodoalkanol 7, in the course of radical addition of perfluoroalkyl iodides 3 to ethenylcyclopentenol (8) or diethenylcyclopentanediol (9), respectively.

Keywords: Cyclopentadienes; Cyclopentenes; Nucleophilic additions; Epoxides; Radical additions; Perfluoroalkylations; Fluorophilic ligands; Fluorous chemistry; Dehydrations.

References: 38 live references.