Arx 500 mhz spectrometer

¹H- and ¹³C-NMR spectra were obtained in CDCl₃ on a Bruker ARX-500 MHz spectrometer using TMS as an internal standard. Electrospray Ionization Mass Spectra (ESI-MS) were obtained on a Thermo Finnigan TSQ7000 triple-quadrupole instrument with an API2 source. Elemental analyses were performed by Atlantic Microlab, Inc. (Norcross, GA). An ORTEC HPGe detector outfitted with Genie multichannel analysis software was used to assay ⁷⁷Ge and ⁷⁷As liquid samples. Reversed phase HPLC (RP-HPLC) was performed using a Shimadzu Prominence HPLC system equipped with a pump, controller, Prominence UV-Vis detector (model SPD20-AV) set to 254 nm and coupled to a Beckman 170 NaI(Tl) radioisotope detector. An Eckert & Ziegler Bioscan AR-2000 Imager using LabLogic Win-Scan imaging scanner software (Version 2.2(11)) was used for scanning radioTLC plates. The gradient system for RP-HPLC using a Thermo Scientific BetaBasic 18 (5 μm, 150 mm x 4.6 mm) column was as follows: 3 minutes at 60/40 ACN/H₂O w/ 0.1 % TFA, followed by a linear gradient to 75/25 over 7 min, and to 95/5 over 10 min, all at a flow rate of 1 mL/min.

All materials were purchased from either Sigma-Aldrich (Milwaukee, WI) or ThermoFisher Scientific (Pittsburgh, PA). Reactions were monitored by ¹H, ⁷⁷Se-NMR and high performance liquid chromatography-mass spectrometry (LCMS). ¹H, ¹³C and ⁷⁷Se-NMR were performed on either a Varian or Bruker ARX 500 MHz spectrometer at 25 °C. LCMS was executed using an ABI Sciex 4000QTrap Pro LCMS equipped with a C18 column in positive-ESI mode. Chemical shifts for ¹H and ⁷⁷Se-NMR are reported in parts per million (ppm) relative to water at 25 °C (δ = 4.79 ppm for ¹H-NMR) or KSeCN (δ = −273 ppm for ⁷⁷Se-NMR). All reactions were performed using oven-dried glassware, and all reagents were used as received.