3 Experimental Section
3.1 General Information
Glassware and Techniques: Unless otherwise indicated, no glassware was
flame dried before use, and all reactions were performed under an air atmosphere, not using standard Schlenk-techniques. Reagents and Solvents:
Unless otherwise stated, all reagents and solvents were used as received
from commercial suppliers. Reaction Monitoring: Reaction progress was
monitored using thin layer chromatography (TLC) on aluminium sheets
coated with silica gel 60 with 0.2 mm thickness (Pre-coated TLC-sheets
ALUGRAM
© Xtra SIL G/UV 254 ). Visualisation was achieved either by
UV light (254 nm and 363 nm), by treatment with potassium permanganate and heat, or by treatment with ethanolic phosphomolybdic acid and
heat. Column Chromatography: Flash column chromatography was
performed using silica gel 60 (230 to 400 Mesh, Merck and co.). NMR
Spectra: All NMR spectra were recorded on Bruker Avance III 600 or
Avance III 700 spectrometers. Chemical shifts (δ) were given in ppm, referenced to the peak of tetramethylsilane (TMS), using residual non-deuterated
solvent as internal standard (
1 H: δ(CDCl 3 ) = 7.26 ppm;
13 C: δ(CDCl 3 ) =
77.16 ppm).
[54] Coupling constants (J) were quoted in Hz. Spectroscopy
splitting patterns were designated as singlet (s), doublet (d), triplet (t),
quartet (q), quintet (quint), or combinations thereof. Splitting patterns that
could not be interpreted or easily visualised were designated as multiplet (m).
Mass Spectra: Mass spectra were obtained using a Bruker maXis spectrometer with ESI-TOF. IR Spectra: Neat infra-red spectra were recorded
using a Perkin-Elmer Spectrum 100 FT-IR spectrometer. Wavenumbers
(˜ ν) were reported in cm
−1 . Optical rotation: Specific rotation ([α]
20
D )
was determined on a SCHMIDT+HAENSCH UniPol L 2000 polarimeter at
© The Editor(s) (if applicable) and The Author(s), under exclusive license to
Springer Fachmedien Wiesbaden GmbH, part of Springer Nature 2020
C. Knittl-Frank, A Concise Semisynthesis of Hederagonic Acid, BestMasters,
https://doi.org/10.1007/978-3-658-30011-1_3
3.1 General Information
Glassware and Techniques: Unless otherwise indicated, no glassware was
flame dried before use, and all reactions were performed under an air atmosphere, not using standard Schlenk-techniques. Reagents and Solvents:
Unless otherwise stated, all reagents and solvents were used as received
from commercial suppliers. Reaction Monitoring: Reaction progress was
monitored using thin layer chromatography (TLC) on aluminium sheets
coated with silica gel 60 with 0.2 mm thickness (Pre-coated TLC-sheets
ALUGRAM
© Xtra SIL G/UV 254 ). Visualisation was achieved either by
UV light (254 nm and 363 nm), by treatment with potassium permanganate and heat, or by treatment with ethanolic phosphomolybdic acid and
heat. Column Chromatography: Flash column chromatography was
performed using silica gel 60 (230 to 400 Mesh, Merck and co.). NMR
Spectra: All NMR spectra were recorded on Bruker Avance III 600 or
Avance III 700 spectrometers. Chemical shifts (δ) were given in ppm, referenced to the peak of tetramethylsilane (TMS), using residual non-deuterated
solvent as internal standard (
1 H: δ(CDCl 3 ) = 7.26 ppm;
13 C: δ(CDCl 3 ) =
77.16 ppm).
[54] Coupling constants (J) were quoted in Hz. Spectroscopy
splitting patterns were designated as singlet (s), doublet (d), triplet (t),
quartet (q), quintet (quint), or combinations thereof. Splitting patterns that
could not be interpreted or easily visualised were designated as multiplet (m).
Mass Spectra: Mass spectra were obtained using a Bruker maXis spectrometer with ESI-TOF. IR Spectra: Neat infra-red spectra were recorded
using a Perkin-Elmer Spectrum 100 FT-IR spectrometer. Wavenumbers
(˜ ν) were reported in cm
−1 . Optical rotation: Specific rotation ([α]
20
D )
was determined on a SCHMIDT+HAENSCH UniPol L 2000 polarimeter at
© The Editor(s) (if applicable) and The Author(s), under exclusive license to
Springer Fachmedien Wiesbaden GmbH, part of Springer Nature 2020
C. Knittl-Frank, A Concise Semisynthesis of Hederagonic Acid, BestMasters,
https://doi.org/10.1007/978-3-658-30011-1_3