All reactions were carried out under an atmosphere of nitrogen in oven-dried glassware with magnetic stirring, unless otherwise indicated. Toluene, dichloromethane, tetrahydrofuran, acetonitrile and diethyl ether were purified by an Innovative Technology Solvent Delivery System. Chemicals were used as obtained from the suppliers. Flash chromatography was performed with Silicycle silica gel 60 (0.040-0.063 μm grade) or acidic alumina (C. Roth, Aluminium oxide 90 acidic). Analytical thin-layer chromatography was performed with commercial glass plates coated with 0.25 mm silica gel (E. Merck, Kieselgel 60 F254). Compounds were either visualised under UV-light at 254 nm or by dipping the plates in an aqueous potassium permanganate solution followed by heating. Proton nuclear magnetic resonance ( 1 H-NMR) data were acquired on a Bruker AV400 (400 MHz) or a Bruker DRX600 (600 MHz). Chemical shifts (δ) are reported in parts per million (ppm) relative to incompletely deuterated CDCl3 (s, 7.26 ppm), C6D6 (s, 7.16 ppm), CD3OD (p, 3.31 ppm). Splitting patterns are designated as s, singlet; d, doublet; t, triplet; q, quartet; p, pentet; dd, doublet of doublets; qd, quadruplet of dublets; m, multiplet; br, broad. Proton decoupled Carbon-13 nuclear magnetic resonance ( 13 C-NMR) data were acquired on a Bruker AV400 (100 MHz) and a Bruker DRX600 (150 MHz) spectrometer. Chemical shifts are reported in ppm relative to CDCl3 (77.16 ppm), C6D6 (128.06 ppm), CD3OD (49.00 ppm). Proton decoupled Fluorine-19 nuclear magnetic resonance ( 19 F-NMR) were acquired at 376 MHz on a Bruker AV400 spectrometer. Infrared (IR) data were recorded on an Alpha-P Bruker FT-IR Spectrometer. Absorbance frequencies are reported in reciprocal centimeters (cm -1 ). HRMS measurements were performed by an Agilent LC-MS TOF. High resolution mass is given in m/z. Enantiomeric excesses were measured on an Agilent or Waters HPLC, or on a Thar SFC Investigator system using chiral stationary phase columns. Optical rotations were measured on a Polartronic M polarimeter using a 0.5 cm cell with a Na 589 nm filter. X-ray analysis was performed by Dr. R. Scopelliti and Dr. F. Fadaei Tirani at the EPF Lausanne.