dC = -2.3 + 9.1a + 9.4b - 2.5g + 0.3d + 0.1e + S(steric corrections) ppm
where: a,b,g,d,e are the numbers of carbon atoms in the a,b,g,d,e positions relative to the carbon atom observed
Steric corrections are derived from the following table (use all that apply, even if they apply more than once).
Ce- Cd-Cg- Cb-Ca- C-Ca-Cb- Cg-Cd- Ce
Steric Corrections (ppm) |
||||
| Type of Attached Carbon | ||||
| Observed Carbon Atom | Primary | Secondary | Tertiary | Quaternary |
| Primary | 0.0 | 0.0 | -1.1 | -3.4 |
| Secondary | 0.0 | 0.0 | -2.5 | -7.5 |
| Tertiary | 0.0 | -3.7 | -9.5 | -15.0 |
| Quaternary | -1.5 | -8.4 | -15.0 | -25.0 |
 |
|
| dC1 = -2.3 + 9.1(1) + 9.4(3) - 2.5(1) + [1(-3.4)] | = 29.1 ppm |
| Observed: | 29.1 ppm |
| dC2 = -2.3 + 9.1(4) + 9.4(1) + [3(-1.5) + 1(-8.4)] | = 30.6 ppm |
| Observed: | 30.6 ppm |
| dC3 = -2.3 + 9.1(2) + 9.4(3) + [1(-7.5)] | = 36.6 ppm |
| Observed: | 36.9 ppm |
| dC4 = -2.3 + 9.1(1) + 9.4(1) - 2.5(3) + [1(0.0)] | = 8.7 ppm |
| Observed: | 8.9 ppm |
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