Field-stepped direct detection electron paramagnetic resonance was written by Yu, Zhelin;Liu, Tengzhi;Elajaili, Hanan;Rinard, George A.;Eaton, Sandra S.;Eaton, Gareth R.. And the article was included in Journal of Magnetic Resonance in 2015.Application In Synthesis of (2R,3R,4S,5R,6R)-2-(Acetoxymethyl)-6-(((2S,3S,4R,5R)-3,4-diacetoxy-2,5-bis(acetoxymethyl)tetrahydrofuran-2-yl)oxy)tetrahydro-2H-pyran-3,4,5-triyl triacetate This article mentions the following:
The widest scan that had been demonstrated previously for rapid scan EPR was a 155 G sinusoidal scan. As the scan width increases, the voltage requirement across the resonating capacitor and scan coils increases dramatically and the background signal induced by the rapidly changing field increases. An alternate approach is needed to achieve wider scans. A field-stepped direct detection EPR method that is based on rapid-scan technol. is now reported, and scan widths up to 6200 G have been demonstrated. A linear scan frequency of 5.12 kHz was generated with the scan driver described previously. The field was stepped at intervals of 0.01 to 1 G, depending on the linewidths in the spectra. At each field data for triangular scans with widths up to 11.5 G were acquired. Data from the triangular scans were combined by matching DC offsets for overlapping regions of successive scans. This approach has the following advantages relative to CW, several of which are similar to the advantages of rapid scan. (i) In CW if the modulation amplitude is too large, the signal is broadened. In direct detection field modulation is not used. (ii) In CW the small modulation amplitude detects only a small fraction of the signal amplitude. In direct detection each scan detects a larger fraction of the signal, which improves the signal-to-noise ratio. (iii) If the scan rate is fast enough to cause rapid scan oscillations, the slow scan spectrum can be recovered by deconvolution after the combination of segments. (iv) The data are acquired with quadrature detection, which permits phase correction in the post processing. (v) In the direct detection method the signal typically is oversampled in the field direction. The number of points to be averaged, thereby improving the signal-to-noise ratio, is determined in post processing based on the desired field resolution A degased lithium phthalocyanine sample was used to demonstrate that the linear deconvolution procedure can be employed with field-stepped direct detection EPR signals. Field-stepped direct detection EPR spectra were obtained for Cu2+ doped in Ni(diethyldithiocarbamate)2, Cu2+ doped in Zn tetratolylporphyrin, perdeuterated tempone in sucrose octaacetate, vanadyl ion doped in a parasubstituted Zn tetratolylporphyrin, Mn2+ impurity in CaO, and an oriented crystal of Mn2+ doped in Mg(acetylacetonate)2(H2O)2. In the experiment, the researchers used many compounds, for example, (2R,3R,4S,5R,6R)-2-(Acetoxymethyl)-6-(((2S,3S,4R,5R)-3,4-diacetoxy-2,5-bis(acetoxymethyl)tetrahydrofuran-2-yl)oxy)tetrahydro-2H-pyran-3,4,5-triyl triacetate (cas: 126-14-7Application In Synthesis of (2R,3R,4S,5R,6R)-2-(Acetoxymethyl)-6-(((2S,3S,4R,5R)-3,4-diacetoxy-2,5-bis(acetoxymethyl)tetrahydrofuran-2-yl)oxy)tetrahydro-2H-pyran-3,4,5-triyl triacetate).
(2R,3R,4S,5R,6R)-2-(Acetoxymethyl)-6-(((2S,3S,4R,5R)-3,4-diacetoxy-2,5-bis(acetoxymethyl)tetrahydrofuran-2-yl)oxy)tetrahydro-2H-pyran-3,4,5-triyl triacetate (cas: 126-14-7) belongs to tetrahydrofuran derivatives. Tetrahydrofurans and furans are important oxygen-containing heterocycles that often exhibit interesting properties for biological applications or applications in the cosmetic industry. Commercial tetrahydrofuran contains substantial water that must be removed for sensitive operations, e.g. those involving organometallic compounds. Although tetrahydrofuran is traditionally dried by distillation from an aggressive desiccant, molecular sieves are superior.Application In Synthesis of (2R,3R,4S,5R,6R)-2-(Acetoxymethyl)-6-(((2S,3S,4R,5R)-3,4-diacetoxy-2,5-bis(acetoxymethyl)tetrahydrofuran-2-yl)oxy)tetrahydro-2H-pyran-3,4,5-triyl triacetate
Referemce:
Tetrahydrofuran – Wikipedia,
Tetrahydrofuran | (CH2)3CH2O – PubChem