Extended Data Table 1 Paramagnetic NMR shifts for 3, 4 and 7

From: Four-electron reduction of benzene by a samarium(ii)-alkyl without the addition of external reducing agents

Compound

Proton group

Experimental (ppm)

Calculated (ppm)

3

BDIDicyp CH

−17.39

−17.92

BDIDicyp CH3

−3.48

−9.97

4

BDIDicyp CH

+5.76

+5.80

BDIDicyp CH3

+3.60

+10.20

7

BDIDicyp CH

+2.94

+3.76

BDIDicyp CH3

+1.92

+2.50

  1. Calculated values obtained from SA-CASSCF-SO calculations using solid-state structures from X-ray diffraction. Calculated using the equation: \({\delta }_{{{\rm{PCS}}}}=\frac{1}{{N}_{A}{r}^{3}}\left(\left({\chi }_{{zz}}-{\chi }_{{\rm{av}}}\right)\frac{2{z}^{2}-{x}^{2}-{y}^{2}}{2{r}^{2}}+\left({\chi }_{{xx}}-{\chi }_{{yy}}\right)\frac{{x}^{2}-{y}^{2}}{2{r}^{2}}\right.\)\(\left.+{\chi }_{{xy}}\frac{2{xy}}{{r}^{2}}+{\chi }_{{xz}}\frac{2{xz}}{{r}^{2}}+{\chi }_{{yz}}\frac{2{yz}}{{r}^{2}}\right)\) where NA is Avogadro’s number, r is the distance between Sm and the proton in question in metres, x, y and z are the Cartesian coordinates of the proton in question in metres where Sm is defined as the origin, χ is the molar magnetic susceptibility tensor in CGS EMU units (cm3 mol−1) and χav = (χxx + χyy + χzz)/3. Calculated CH3 shift is averaged over all six equivalent protons in the X-ray structure.
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