Avance 3 500 ft nmr spectrometer

Infrared spectra were recorded at ambient conditions with a FT-Nicolet IR 200 equipment or as ATR-FTIR spectra by using a Biorad FTS-165 or a Nicolet iS 10 spectrometer from Thermo Scientific. NMR spectra (500.3 MHz for ¹H, 125.7 MHz for ¹³C, 160.5 MHz for ¹¹B) were recorded using a Bruker Avance III 500 FT-NMR spectrometer at ambient temperature. Chemical shifts are reported in ppm downfield from tetramethylsilane with the solvent as reference signal (¹H NMR: δ (CDCl₃) = 7.26 ppm; ¹³C{¹H} NMR: δ (CDCl₃) = 77.16 ppm). The melting points were determined with a Gallenkamp MFB 595 010 M melting point apparatus. Elemental analyses were performed with a Thermo FlashEA 1112 Series instrument (ThermoFisher). High-resolution mass spectra were recorded using a micrOTOF QII Bruker Daltonite workstation.

Melting points (mp) were determined using a Büchi M560 apparatus (Büchi Labortechnik AG, Flawil, Switzerland) and are uncorrected. Optical rotations ([α]_D) were measured using a P-2000 polarimeter (JASCO, Easton, MD, USA). Infrared (IR) spectra were reported in wave numbers (cm⁻¹) using an IR Prestige-21/FTIR-8400S Fourier transform infrared spectrophotometer (Shimadzu Kyoto, Kyoto Prefecture, Japan). ¹H and ¹³C-NMR spectra were recorded using a Bruker AVANCE III 500 FT-NMR spectrometer (Bruker, Rheinstetten, Germany) at room temperature, and the chemical shifts are reported in ppm using tetramethylsilane (TMS) as the internal standard. Mass spectra (MS) were obtained using a LCQ ion-trap mass spectrometer using the electrospray ionization (ESI) technique (Thermo-Finnigan, Mundelein, IL, USA). High-resolution electrospray ionization mass spectra (HRESI-MS) were recorded on a LTQ orbitrap XL hybrid ion trap-orbitrap mass spectrometer (Thermo Scientific, Waltham, MA, USA). Column chromatography was performed on 230−400 mesh silica gel.

All reactions treating air-sensitive compounds were performed under argon or nitrogen atmosphere using a high-vacuum line, standard Schlenk techniques, or a glove box, as well as dry and oxygen-free solvents. ¹H (500 MHz), ¹¹B (160 MHz), ¹³C (125 MHz), and ²⁹Si (99 MHz) NMR spectra were recorded on a Bruker Avance III 500 FT NMR spectrometer. The ¹H NMR chemical shifts in benzene-d₆ (C₆D₆) were referenced to the residual C₆D₅H signal (δ 7.16). The ¹³C{¹H} and ²⁹Si{¹H} NMR chemical shifts were relative to Me₄Si (δ 0.00). The ¹¹B NMR chemical shifts were relative to BF₃·OEt₂ (δ 0.00). Sampling of air-sensitive compounds was carried out using a VAC NEXUS 100027-type glove box. Mass spectra were recorded on a Bruker Daltonics SolariX 9.4T or a JEOL JMS-Q1050 spectrometer. UV-vis spectra were recorded on a JASCO V-660 spectrometer.