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An operationally simple method for generating enantioenriched 2-oxazolidinones from N-Boc amines and monoor trans-disubstituted alkenes via chiral organoselenium catalysis is described. Critical to the success of the transformation was the inclusion of triisopropylsilyl chloride (TIPSCl), likely because it sequestered fluoride generated by the oxidant (N-fluorocollidinium tetrafluoroborate) throughout the reaction and suppressed side reactivity. The scope of both the amine and alkene substrates was explored, generating a variety of 2-oxazolidinones in modest to high yields with high enantioselectivities 

Polythiophenes (PTs) constitute a diverse array of promising materials for conducting polymer applications. However, many of the synthetic methods to produce PTs have been optimized only for the prototypical alkyl-substituted example poly(3-hexylthiophene) (P3HT). Improvement of these methods beyond P3HT is key to enabling the widespread application of PTs. In this work, P3HT and two ether-substituted PTs poly(2-dodecyl-2H,3H-thieno[3,4-b][1,4]dioxine) (PEDOT-C12) and poly(3,4-bis(hexyloxy)thiophene) (PBHOT) are synthesized by the FeCl3-initiated oxidative method under different conditions. Polymerization was carried out according to a common literature procedure (“reverse addition”) and a modified method (“standard addition”), which differ by the solvent system and the order of addition of reagents to the reaction mixture. Gel-permeation chromatography (GPC) was performed to determine the impact of the different methods on the molecular weights (Mw) and degree of polymerization (Xw) of the polymers relative to polystyrene standards. The standard addition method produced ether-substituted PTs with higher Mw and Xw than those produced using the reverse addition method for sterically unhindered monomers. For P3HT, the highest Mw and Xw were obtained using the reverse addition method. The results show the oxidation potential of the monomer and solution has the greatest impact on the yield and Xw obtained and should be carefully considered when optimizing the reaction conditions for different monomers.