All reactions and handling of air-and moisture sensitive compounds were carried out under dried argon atmosphere (Air Liquide, 99.995 %) using conventional Schlenk techniques. Glassware were baked out and silanized prior to use. Sample preparation for further analysis was carried out in an Argon filled glovebox (Mbraun). All commercially available chemicals were used without further purification. Solvents were dried by a solvent purification system (MBraun) and stored over molecular sieves (4 Å) under an argon atmosphere. NMRsolvents were degassed and dried over activated molecular sieves (4 Å).