NMR Analysis
This page contains a collection of information how to reference analytical data. We provide this page to describe the preferred formatting of analytical evaluations in the Chemotion repository. The given preferences follow standards of journals/publishers and other stakeholders wherever we could find them. Currently, in particular the format of the metadata of the analytical data (everything before "=") is not reviewed critically. If you have suggestions and comments: please let us know or provide your ideas via the issue tracking option. https://github.com/ComPlat/chemotion_saurus/issues Updated: 01.03.2024
Inline notation for 1H NMR data
The inline notation gives a short summary of the metadata and a list of all signals or signals group (for signals that cannot be separated from each other). For each signal, the shift should be provided along with at least the following information given in parentheses: multiplet abbreviations, coupling constants, and number of atoms represented by each signal should be provided. (see example No 1)
Examples for desired formatting:
(1) Standard example:
1H NMR (400 MHz, CDCl3, 25 °C): δ [ppm] = 7.28 (dd, J = 1.6, 7.7 Hz, 1H), 7.14 (ddd, J = 8.2, 7.3, 1.6 Hz, 1H), 6.74–6.66 (m, 2H), 4.94 (s, 2H), 4.04 (br.s, 2H), 2.12 (s, 3H).
(2) Example for a solvent that needs signal definition:
1H NMR (400 MHz, DMF-d7 [2.75 ppm], 25 °C): δ [ppm] = 7.28
(dd, J = 7.7, 1.6 Hz, 1H), 7.14 (ddd, J = 8.2, 7.3, 1.6 Hz, 1H), 6.74–6.66
(m, 2H), 4.94 (s, 2H), 4.04 (br.s, 2H), 2.12 (s, 3H).
(3) Example with solvent ratio where CDCl3 is used as a reference:
1H NMR (400 MHz, CDCl3/DMF-d7 5:1, 25 °C): δ [ppm] = 7.28 (dd, J = 7.7, 1.6 Hz, 1H), 7.14 (ddd, J = 8.2, 7.3, 1.6 Hz, 1H), 6.74–6.66 (m, 2H), 4.94 (s, 2H), 4.04 (br.s, 2H), 2.12 (s, 3H).
(4) Example with additional standard TMS:
1H NMR (400 MHz, CDCl3, 25 °C, TMS): δ [ppm] = 7.28 (dd, J = 7.7, 1.6 Hz, 1H), 7.14 (ddd, J = 8.2, 7.3, 1.6 Hz, 1H), 6.74–6.66 (m, 2H), 4.94 (s, 2H), 4.04 (br.s, 2H), 2.12 (s, 3H).
(5) Example with order of coupling constants, if available and required:
1H NMR (400 MHz, DMF-d7 [2.75 ppm], 25 °C): δ [ppm] = 7.28 (dd, J = 7.7, 1.6 Hz, 1H), 7.14 (ddd, 3 J = 8.2, 3 J = 7.3, 4 J = 1.6 Hz, 1H), 6.74–6.66 (m, 2H), 4.94 (s, 2H), 4.04 (br.s, 2H), 2.12 (s, 3H).
(6) Example with couplings which are not H,H couplings:
1H NMR (400 MHz, DMF-d7 [2.75 ppm], 25 °C): δ [ppm] = 7.28 (dd, J = 7.7, 1.6 Hz, 1H), 7.14 (ddd, 3 J = 8.2, 3 J H,F = 7.3, 4 J = 1.6 Hz, 1H), 6.74–6.66 (m, 2H), 4.94 (s, 2H), 4.04 (br.s, 2H), 2.12 (s, 3H).
(7) Example with missing protons and impurities:
1H NMR (400 MHz, MeOD-d4, 25 °C): δ [ppm] = 7.28 (dd, J = 7.7, J = 1.6 Hz, 1H), 7.14 (ddd, 3 J = 8.2, 3 J H,F = 7.3, 4 J = 1.6 Hz, 1H), 6.74–6.66 (m, 2H), 4.94 (s, 2H), 4.04 (br.s, 2H), 2.12 (s, 3H). Missing signal (1H, OH) due to H/D exchange in MeOD. Impurities: 10% impurities due to the formation of the cis-isomer during the measurement of the sample.
(8) Example for isomers:
1H NMR (500 MHz, MeOD-d4 [3.31 ppm]): δ [ppm] = 13.23 (bs, 0.4H, CO2H-isomer1), 12.98 (bs, 0.6H, CO2H-isomer2), 8.24 (d, 0.6H, J = 1.5 Hz, CH-isomer2), 8.21 (d, 0.4H, J = 1.5 Hz, CH-isomer1), 3.30 (s, 3H, CH3-isomer1+-isomer2) etc.
(9) Example for assignment according to option 1:
1H NMR (250 MHz, CDCl3): δ [ppm] = 7.08 (dd, J = 7.6, 1.2 Hz, 1H, H-5), 6.97 (ps.td, J = 7.6, 1.2 Hz, 1H, H-7), 6.63 (ps.td, J = 7.6, 1.2 Hz, 1H, H-6), 6.48 (dd, J = 7.6, 1.2 Hz, 1H, H-8), 3.85 (bs, 1H, NH), 3.40–3.22 (m, 2H, H-2), 3.02–2.84 (m, 1H, H-4), 2.07–1.92 (m, 1H, Ha-3), 1.76–1.61 (m, 1H, Hb-3), 1.30 (d, J = 7.0 Hz, 3H, CH3).
(10) Example for assignment according to option 2:
1H NMR (250 MHz, CDCl3): δ [ppm] = 7.08 (dd, J = 7.6, 1.2 Hz, 1H, NHCCH), 6.97 (ps.td, J = 7.6, 1.2 Hz, 1H, CHCC H), 6.63 (ps.td, J = 7.6, 1.2 Hz, 1H, NHCCHCH), 6.48 (dd, J = 7.6, 1.2 Hz, 1H, CHCCHCH), 3.85 (bs, 1H, NH), 3.40–3.22 (m, 2H, NHCH 2), 3.02–2.84 (m, 1H, CHCH3), 2.07–1.92 (m, 1H, CH a), 1.76–1.61 (m, 1H, CHb), 1.30 (d, J = 7.0 Hz, 3H, CH3).
(11) Example for assignment according to option 3:
1H NMR (250 MHz, CDCl3): δ [ppm] = 7.08 (dd, J = 7.6, 1.2 Hz, 1H, Har), 6.97 (ps.td, J = 7.6, 1.2 Hz, 1H, H ar), 6.63 (ps.td, J = 7.6, 1.2 Hz, 1Har), 6.48 (dd, J = 7.6, 1.2 Hz, 1H, Har), 3.85 (bs, 1H, NH), 3.40–3.22 (m, 2H, H-2), 3.02–2.84 (m, 1H, H-4), 2.07–1.92 (m, 1H, Ha -3), 1.76–1.61 (m, 1H, Hb-3), 1.30 (d, J = 7.0 Hz, 3H, CH 3).
Alternatives for giving metadata
The following ways to cite the metadata for NMR are preferred: 1H NMR (400 MHz, CDCl3 [7.27 ppm], ppm) δ = 1H NMR (400 MHz, CDCl3, 25 °C): δ [ppm] =