Structural characterization and quantitation of compound loading of disubstituted benzoates bound to Wang resin through high‐resolution magic angle spinning NMR spectroscopy

Abstract

The combination of 1D and 2D high-resolution magic angle spinning NMR experiments led to the assignment of the proton and carbon resonances for several disubstituted benzoates bound to a polystyrene resin through a Wang linker. It is shown that the signal corresponding to the methylene protons of the linker can be utilized to monitor the solid-phase reactions and determine the loading of the compounds on the resin.

Micro-environmental fine-tuning of electronic and kinetic properties of photochromic dyes

“…Structural characterisation was carried out using FT-IR spectroscopy showing proof of attachment, and 1 H-MAS to determine percentage of resin reactive sites containing SP molecules following a previously reported procedure. 35 Two particle sizes were chosen, 50 and 100 mm, designated as 4a (WR-SP 50 mm) and 4b (WR-SP 100 mm), producing coloured particles labelled 5a (WR-MC 50 mm) and 5b (WR-MC 100 mm) following UV irradiation. Previously 1b was chosen having a suitable linker group for attachment to the resin.…”

13C SPE MAS measurement of ligand concentration in compressible chromatographic beads

“…Our study also connects to characterization of silica‐based chromatography media with solid‐state NMR, a field that has been active for many years. Besides investigating the molecular dynamics of components immobilized on silica or on polymeric resins and the interactions between bound ligands and analytes in the mobile phase, a few MAS NMR studies concerned the ligand concentration in stationary phases such as chromatography media or resins for solid‐phase organic synthesis . Here, we present for the first time quantitative MAS NMR to measure ligand concentration in a chromatography medium based on a soft polysaccharide hydrogel resin.…”

Solid-Phase Synthesis of Novel Trimers Containing a Phenylstatine Core and Analysis by High-Resolution Magic Angle Spinning

“…Inspection of the 1 H spectrum revealed the appearance of four weak signals between 7.2 and 7.8 ppm that corresponded to the aromatic protons of the Fmoc protecting group, thus confirming the incorporation of the residue into the resin (Figure b). The yields of solid-phase reactions were determined by comparison of the intensity of a proton signal of the resin-bound product with that of a proton signal of the linker. , In this case, the aromatic signal of the Fmoc protecting group at 7.74 ppm, which accounted for two aromatic protons and appeared to be well-separated from the resin background, was compared with that of the methylene protons of the linker (H1 in Figure b). The determined yields were quite low (10−20%), in complete agreement with those obtained through the conventional Fmoc quantification procedure upon cleavage of the protecting group from the resin.…”