Chem. J. Chinese Universities ›› 2022, Vol. 43 ›› Issue (6): 20220084.doi: 10.7503/cjcu20220084
• Analytical Chemistry • Previous Articles Next Articles
Received:
2022-02-12
Online:
2022-06-10
Published:
2022-03-17
Contact:
WANG Liyan
E-mail:wangliyan@vip.sina.com
Supported by:
CLC Number:
TrendMD:
MIN Jing, WANG Liyan. 1H NMR Study on the Conformation of Aromatic Amides Limited by Three-center Hydrogen Bonds[J]. Chem. J. Chinese Universities, 2022, 43(6): 20220084.
βH | δβH(CDCl3) | δβH(CD3NO2) | δβH(CD3CN) | δβH(DMSO) | Δ(δβH)?1 | Δ(δβH)?2 | Δ(δβH)?3 |
---|---|---|---|---|---|---|---|
H6 of CO?O | 8.31 | 8.19 | 8.19 | 8.11 | 0.20 | 0.08 | 0.08 |
H6 of CF?O | 8.18 | 8.08 | 8.05 | 7.87 | 0.31 | 0.21 | 0.18 |
H3 of CPy?O | 8.30 | 8.23 | 8.23 | 8.20 | 0.10 | 0.03 | 0.03 |
H2,H6 of CPh?O | 7.90 | 7.93 | 7.95 | 7.97 | -0.07 | -0.04 | -0.02 |
Table 1 Chemical shifts of β H of CO-O, CF-O, CPy-O and CPh-O in CDCl3, CD3NO2, CD3CN and DMSO-d6 and their solvent-related changes*
βH | δβH(CDCl3) | δβH(CD3NO2) | δβH(CD3CN) | δβH(DMSO) | Δ(δβH)?1 | Δ(δβH)?2 | Δ(δβH)?3 |
---|---|---|---|---|---|---|---|
H6 of CO?O | 8.31 | 8.19 | 8.19 | 8.11 | 0.20 | 0.08 | 0.08 |
H6 of CF?O | 8.18 | 8.08 | 8.05 | 7.87 | 0.31 | 0.21 | 0.18 |
H3 of CPy?O | 8.30 | 8.23 | 8.23 | 8.20 | 0.10 | 0.03 | 0.03 |
H2,H6 of CPh?O | 7.90 | 7.93 | 7.95 | 7.97 | -0.07 | -0.04 | -0.02 |
γH | δγH(CDCl3) | δγH(CD3NO2) | δγH(CD3CN) | δγH(DMSO) | Δ(δγH)?1 | Δ(δγH)?2 | Δ(δγH)?3 |
---|---|---|---|---|---|---|---|
H6b of CO?O | 8.65 | 8.53 | 8.55 | 8.48 | 0.17 | 0.05 | 0.07 |
H6b of CF?O | 8.57 | 8.45 | 8.44 | 8.14 | 0.43 | 0.31 | 0.30 |
H6b of CPy?O | 8.62 | 8.52 | 8.54 | 8.45 | 0.17 | 0.07 | 0.09 |
H6b of CPh?O | 8.54 | 8.38 | 8.34 | 7.80 | 0.74 | 0.58 | 0.54 |
Table 2 Chemical shifts of γ H of CO-O, CF-O, CPy-O and CPh-O in CDCl3, CD3NO2, CD3CN and DMSO-d6 and their solvent-related changes*
γH | δγH(CDCl3) | δγH(CD3NO2) | δγH(CD3CN) | δγH(DMSO) | Δ(δγH)?1 | Δ(δγH)?2 | Δ(δγH)?3 |
---|---|---|---|---|---|---|---|
H6b of CO?O | 8.65 | 8.53 | 8.55 | 8.48 | 0.17 | 0.05 | 0.07 |
H6b of CF?O | 8.57 | 8.45 | 8.44 | 8.14 | 0.43 | 0.31 | 0.30 |
H6b of CPy?O | 8.62 | 8.52 | 8.54 | 8.45 | 0.17 | 0.07 | 0.09 |
H6b of CPh?O | 8.54 | 8.38 | 8.34 | 7.80 | 0.74 | 0.58 | 0.54 |
βH | δβH(CDCl3) | δβH(CD3NO2) | δβH(CD3CN) | δβH(DMSO) | Δ(δβH)?1 | Δ(δβH)?2 | Δ(δβH)?3 |
---|---|---|---|---|---|---|---|
H6 of CO?F | 8.31 | 8.18 | 8.17 | 7.96 | 0.35 | 0.22 | 0.21 |
H6 of CF?F | 8.19 | 8.04 | 7.97 | 7.72 | 0.47 | 0.32 | 0.25 |
H3 of CPy?F | 8.30 | 8.24 | 8.23 | 8.14 | 0.16 | 0.10 | 0.09 |
H2,H6 of CPh?F | 7.90 | 7.95 | 7.93 | 7.98 | -0.08 | -0.03 | -0.05 |
Table 3 Chemical shifts of β H of CO-F, CF-F, CPy-F and CPh-F in CDCl3, CD3NO2, CD3CN and DMSO?d6 and their solvent-related changes*
βH | δβH(CDCl3) | δβH(CD3NO2) | δβH(CD3CN) | δβH(DMSO) | Δ(δβH)?1 | Δ(δβH)?2 | Δ(δβH)?3 |
---|---|---|---|---|---|---|---|
H6 of CO?F | 8.31 | 8.18 | 8.17 | 7.96 | 0.35 | 0.22 | 0.21 |
H6 of CF?F | 8.19 | 8.04 | 7.97 | 7.72 | 0.47 | 0.32 | 0.25 |
H3 of CPy?F | 8.30 | 8.24 | 8.23 | 8.14 | 0.16 | 0.10 | 0.09 |
H2,H6 of CPh?F | 7.90 | 7.95 | 7.93 | 7.98 | -0.08 | -0.03 | -0.05 |
γH | δγH(CDCl3) | δγH(CD3NO2) | δγH(CD3CN) | δγH(DMSO) | Δ(δγH)?1 | Δ(δγH)?2 | Δ(δγH)?3 |
---|---|---|---|---|---|---|---|
H6b of CO?F | 8.61 | 8.46 | 8.44 | 8.23 | 0.38 | 0.23 | 0.21 |
H6b of CF?F | 8.51 | 8.30 | 8.21 | 7.79 | 0.72 | 0.51 | 0.42 |
H6b of CPy?F | 8.58 | 8.45 | 8.45 | 8.18 | 0.40 | 0.27 | 0.27 |
H6b of CPh?F | 8.48 | 8.18 | 7.99 | 7.61 | 0.87 | 0.57 | 0.38 |
Table 4 Chemical shifts of γ H of CO-F, CF-F, CPy-F and CPh-F in CDCl3, CD3NO2, CD3CN and DMSO-d6 and their solvent-related changes*
γH | δγH(CDCl3) | δγH(CD3NO2) | δγH(CD3CN) | δγH(DMSO) | Δ(δγH)?1 | Δ(δγH)?2 | Δ(δγH)?3 |
---|---|---|---|---|---|---|---|
H6b of CO?F | 8.61 | 8.46 | 8.44 | 8.23 | 0.38 | 0.23 | 0.21 |
H6b of CF?F | 8.51 | 8.30 | 8.21 | 7.79 | 0.72 | 0.51 | 0.42 |
H6b of CPy?F | 8.58 | 8.45 | 8.45 | 8.18 | 0.40 | 0.27 | 0.27 |
H6b of CPh?F | 8.48 | 8.18 | 7.99 | 7.61 | 0.87 | 0.57 | 0.38 |
βH | δβH(CDCl3) | δβH(CD3NO2) | δβH(CD3CN) | δβH(DMSO) | Δ(δβH)?1 | Δ(δβH)?2 | Δ(δβH)?3 | |
---|---|---|---|---|---|---|---|---|
H6 of CO?Es | 8.19 | 8.10 | 8.08 | 8.00 | 0.19 | 0.10 | 0.08 | |
H6 of CF?Es | 8.07 | 8.02 | 7.99 | 7.91 | 0.16 | 0.11 | 0.08 | |
H3 of CPy?Es | 8.31 | 8.25 | 8.24 | 8.21 | 0.10 | 0.04 | 0.03 | |
H2, H6 of CPh?Es | 8.06 | 8.04 | 8.01 | 7.97 | 0.09 | 0.07 | 0.04 |
Table 5 Chemical shifts of β H of CO-Es, CF-Es, CPy-Es and CPh-Es in CDCl3, CD3NO2, CD3CN and DMSO-d6 and their solvent-related changes*
βH | δβH(CDCl3) | δβH(CD3NO2) | δβH(CD3CN) | δβH(DMSO) | Δ(δβH)?1 | Δ(δβH)?2 | Δ(δβH)?3 | |
---|---|---|---|---|---|---|---|---|
H6 of CO?Es | 8.19 | 8.10 | 8.08 | 8.00 | 0.19 | 0.10 | 0.08 | |
H6 of CF?Es | 8.07 | 8.02 | 7.99 | 7.91 | 0.16 | 0.11 | 0.08 | |
H3 of CPy?Es | 8.31 | 8.25 | 8.24 | 8.21 | 0.10 | 0.04 | 0.03 | |
H2, H6 of CPh?Es | 8.06 | 8.04 | 8.01 | 7.97 | 0.09 | 0.07 | 0.04 |
γH | δγH(CDCl3) | δγH(CD3NO2) | δγH(CD3CN) | δγH(DMSO) | Δ(δγH)?1 | Δ(δγH)?2 | Δ(δγH)?3 |
---|---|---|---|---|---|---|---|
H3b of CO?Es | 8.93 | 8.83 | 8.85 | 8.76 | 0.17 | 0.07 | 0.09 |
H3b of CF?Es | 8.90 | 8.81 | 8.81 | 8.56 | 0.34 | 0.25 | 0.25 |
H3b of CPy?Es | 8.98 | 8.93 | 8.94 | 8.86 | 0.12 | 0.07 | 0.08 |
H3b of CPh?Es | 8.94 | 8.84 | 8.84 | 8.58 | 0.36 | 0.26 | 0.26 |
Table 6 Chemical shifts of γ H of CO-Es, CF-Es, CPy-Es and CPh-Es in CDCl3, CD3NO2, CD3CN and DMSO-d6 and their solvent-related changes*
γH | δγH(CDCl3) | δγH(CD3NO2) | δγH(CD3CN) | δγH(DMSO) | Δ(δγH)?1 | Δ(δγH)?2 | Δ(δγH)?3 |
---|---|---|---|---|---|---|---|
H3b of CO?Es | 8.93 | 8.83 | 8.85 | 8.76 | 0.17 | 0.07 | 0.09 |
H3b of CF?Es | 8.90 | 8.81 | 8.81 | 8.56 | 0.34 | 0.25 | 0.25 |
H3b of CPy?Es | 8.98 | 8.93 | 8.94 | 8.86 | 0.12 | 0.07 | 0.08 |
H3b of CPh?Es | 8.94 | 8.84 | 8.84 | 8.58 | 0.36 | 0.26 | 0.26 |
βH | δβH(CDCl3) | δβH(CD3NO2) | δβH(CD3CN) | δβH(DMSO) | Δ(δβH)?1 | Δ(δβH)?2 | Δ(δβH)?3 |
---|---|---|---|---|---|---|---|
H6 of HO?O | 8.26 | 8.13 | 8.12 | 7.83 | 0.43 | 0.30 | 0.29 |
H6 of HF?F | 8.16 | 8.00 | 7.91 | 7.67 | 0.49 | 0.33 | 0.24 |
H6F of HF?O | 8.15 | 8.12 | 7.93 | 7.68 | 0.47 | 0.44 | 0.25 |
H6O of HF?O | 8.24 | 8.01 | 8.09 | 7.78 | 0.46 | 0.23 | 0.31 |
Table 7 Chemical shifts of β H of HO-O, HF-F and HF-O in CDCl3 and DMSO?d6 and their solvent?related changes*
βH | δβH(CDCl3) | δβH(CD3NO2) | δβH(CD3CN) | δβH(DMSO) | Δ(δβH)?1 | Δ(δβH)?2 | Δ(δβH)?3 |
---|---|---|---|---|---|---|---|
H6 of HO?O | 8.26 | 8.13 | 8.12 | 7.83 | 0.43 | 0.30 | 0.29 |
H6 of HF?F | 8.16 | 8.00 | 7.91 | 7.67 | 0.49 | 0.33 | 0.24 |
H6F of HF?O | 8.15 | 8.12 | 7.93 | 7.68 | 0.47 | 0.44 | 0.25 |
H6O of HF?O | 8.24 | 8.01 | 8.09 | 7.78 | 0.46 | 0.23 | 0.31 |
Aromatic amide | CO?O | CF?O | CPy?O | CO?F | CF?F | CPy?F | CO?Es | CF?Es | CPy?Es |
---|---|---|---|---|---|---|---|---|---|
Δ(δβH) | 0.20 | 0.31 | 0.10 | 0.35 | 0.47 | 0.16 | 0.19 | 0.16 | 0.10 |
Δ(δγH) | 0.17 | 0.43 | 0.17 | 0.38 | 0.72 | 0.40 | 0.17 | 0.34 | 0.12 |
Table 8 Solvent-related changes in chemical shifts of β H and γ H of aromatic amides in CDCl3 and DMSO-d6*
Aromatic amide | CO?O | CF?O | CPy?O | CO?F | CF?F | CPy?F | CO?Es | CF?Es | CPy?Es |
---|---|---|---|---|---|---|---|---|---|
Δ(δβH) | 0.20 | 0.31 | 0.10 | 0.35 | 0.47 | 0.16 | 0.19 | 0.16 | 0.10 |
Δ(δγH) | 0.17 | 0.43 | 0.17 | 0.38 | 0.72 | 0.40 | 0.17 | 0.34 | 0.12 |
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