Satellite ft ir spectrophotometer

The starting compounds, reagents, and solvents (Sigma-Aldrich, Darmstadt, Germany) used in this study were of analytical reagent grade. Thin-layer chromatography was performed on an aluminum plate precoated with layers of silica gel 60F₂₅₄ (Merck, Darmstadt, Germany). The chromatograms were visualized using UV light. The stationary base in column chromatography (70–230 mesh) was high-purity grade silica gel 60 (Merck, Darmstadt, Germany). Melting points were measured once via a Stuart SMP30 apparatus (Stone, Staffordshire, UK). IR spectra were recorded using KBr pellets on a Satellite FT-IR spectrophotometer (Bruker, Madison, WI, USA). ¹H and ¹³C NMR spectra in DMSO-d₆ were recorded using a Varian Unity Plus (500 MHz) instrument (Varian Medical Systems, Palo Alto, CA, USA). The elemental analyses (%C, H, and N) were determined using a Perkin Elmer PE 2400 Series II CHNS analyzer (Perkin-Elmer, Shelton, CT, USA). The results of the elemental analyses were consistent with the calculated values within the ±0.4% range.

The initial compound (Apollo Scientific, Bredbury, UK) and all reagents and solvents (Sigma-Aldrich, Darmstadt, Germany) were of analytical grade. Thin-layer chromatography was performed on Merck silica gel 60F₂₅₄ plates and visualized using UV light. The stationary phase in column chromatography was high-purity Merck silica gel (pore size 60 Å, 70–230 mesh). Elemental analyses (%C, H, N) of all synthesized compounds in the solid form were carried out using a PerkinElmer PE 2400 Series II CHNS analyzer (Perkin-Elmer, Shelton, CT, USA), the results of which were in agreement with the calculated values within the ±0.4% range. IR spectra were recorded as KBr pellets of the solids using a Satellite FT-IR spectrophotometer (Bruker, Madison, WI, USA). The ¹H and ¹³C NMR spectra in DMSO-d₆ were recorded using Varian Unity Plus (500 MHz) and Varian Gemini (200 MHz) instruments (Varian Medical Systems, Palo Alto, CA, USA). Melting points were determined using a Stuart SMP30 apparatus (Stone, Staffordshire, UK) and were uncorrected.

The reagents, solvents, and materials used were of analytical purity (Sigma-Aldrich-Merck KgaA, Darmstadt, Germany). The purity of the products was confirmed by thin-layer chromatography (TLC). In the analysis, silica gel plates were used, and a lamp emitting light with a wavelength of λ = 254 nm was used for detection. The melting points of the compounds obtained were measured once with a Stuart SMP30 (Stone, Staffordshire, UK). IR spectra for potassium bromide pellets of solids were recorded on a Satellite FT-IR spectrophotometer (Bruker, Madison, WI, USA). Standard ¹H and ¹³C NMR spectra were performed in CDCl₃ or DMSO-d₆ using Varian Unity Plus (500 MHz) and Varian Gemini (200 MHz) instruments (Varian Medical Systems, Palo Alto, CA, USA). The ¹H NMR spectra of 1a–c were acquired at various temperatures (233, 243, 253, 263, 273 and 300 K) using a Bruker Avance II Plus 16.4 T spectrometer (Bruker BioSpin, Rheinstetten, Germany) operating at an ¹H frequency (700.16 MHz). The elemental composition of the products was determined on the basis of elemental analysis (% C, H, N), and the obtained results were consistent with the values calculated with a maximum deviation of 0.4%.
Methyl 4-phenylpicolinimidate was synthesized according to method described by us elsewhere [13 (link)] and analytical data were consistent with those obtained by other authors [14 (link)].