Preparative column chromatography was performed on a Biotage Isolera One flash purification system using self-packed SiO 2 cartridges (Macherey-Nagel silica gel 60M, particle size 40-63 µm). TLC were performed on Macherey-Nagel TLC aluminium sheets with a 0.20 mm layer of silica gel 60 with F 254 fluorescence indicator. Dry THF was distilled from sodium benzophenone ketyl under argon, dry DCM was distilled from CaH 2 and DMF was distilled from CaH 2 under reduced pressure and stored with molecular sieve 4 Å. PCl 3 and Et 3 N were distilled and stored under argon prior to use. Other chemicals were bought from Sigma-Aldrich, Acros Organics and Alfa Aesar in reagent grade or better and used as recieved.