Esquire lc spectrometer

Chromatographic purifications were performed by column chromatography using 0.06–0.20 mm silica gel. NMR spectra were measured with a JEOL JNM-ECA 300/600 instrument (JEOL Ltd, Tokyo, Japan). A Bruker Esquire-LC spectrometer (Bruker, Fallanden, Switzerland) was employed to measure electrospray ionization mass spectrometry (ESI-MS). TEM was performed using a Tecnai Spiri 120 KV instrument (FEI, Hillsboro, OR, USA). Rheological properties were measured by a Physica MCR301 rotary rheometer (Anton Paar, Germany) at room temperature.
Triethylamine (Et₃N), benzoyl chloride, toluene, chlorobenzene, o-dichlorobenzene, bromobenzeneand, DMF were purchased from Beijing Chemical Plant (analytical purity). All solid samples requiring drying were vacuum-dried for 5–10 h before use.
p-phenylenediamine, 1-ethyl-3-(dimethylaminopropyl) carbonyl diimide hydrochloride (EDCI), trifluoroacetic acid (TFA) and isophthaloyl dichloride were purchased from J&K Scientific Co., Ltd. (Beijing, China).

Melting points were determined with a Cole-Parmer melting point apparatus (Cole-Parmer, Vernon Hills, IL, USA) (thermometer was uncorrected). IR spectra were recorded on a NEXUS-470 FTIR spectrometer (International Equipment Trading Ltd., Vernon Hills, IL, USA) with KBr pellets. ¹H NMR spectra were recorded with a Bruker DPX300 instrument (Bruker, Billerica, MA, USA) and tetramethylsilane was used as an internal standard. Analytical thin-layer chromatography (TLC) was carried out on precoated plates (silica gel 60 F254) and spots were visualized under ultraviolet light. Elemental analyses (C, H and N) were carried out with a Flash EA 1112 elemental analyzer (Thermo Finnigan, Bremen, Germany). Mass spectra were measured on a Bruker ESQUIRE-LC spectrometer (Bruker, Fallanden, Switzerland). The X-ray crystal diffraction (Bruker, Fallanden, Switzerland) data were collected with a Rigaku Saturn diffractometer at 294(2) K and the crystal structures were calculated using the SHELXL program package and refined by full-matrix least squares procedures at Nankai University (Tianjin, China).

All reagents were purchased from Sigma Aldrich and used without further purification. Preparation of 6,7-Dichloroquinoline-5,8-dione followed a reported procedure [14 (link),19 (link)]. The reaction yields were calculated for the products after chromatographic purification. Thin layer chromatography (TLC): Merck silica gel F₂₅₄ or reversed phase Merck RP-18 F₂₅₄, with visualization using UV light. Flash chromatography (FC): Merck Si 15–25 μm. Preparative thin layer chromatography (PLC): 20 × 20 cm Merck Kieselgel 60 F₂₅₄ 0.5-mm plates. NMR spectra were recorded on a Bruker-Avance 400 spectrometer using a 5-mm BBI probe ¹H at 400 MHz and ¹³C at 100 MHz in CDCl₃ (relative to δ_H 7.25 and δ_C 77.00 ppm), with δ values in ppm and J values in Hz; assignments were supported by heteronuclear single quantum correlation (HSQC) and heteronuclear multiple bond correlation (HMBC) experiments. Electrospray ionization (ESI)-MS mass spectra were recorded using a Bruker Esquire-LC spectrometer by direct infusion of a methanol solution (source temperature 300 °C, drying gas N₂, 4 L min⁻¹, scan range m/z 100 ÷ 1000). Electron ionization (EI) mass spectra (m/z; rel%) and high resolution (HR)-EI data were recorded with a Kratos-MS80 mass spectrometer, heating at 213 °C for 2a–c, at 276 °C for 1a–c and at 417 °C for compound 3, using a home-built computerized acquisition software.