Ibrom K, Boeckmann KU, Kraft R, Holba-Schulz P, Ernst L
Institut fur Organische Chemie, Technische Universitat Braunschweig, Hagenring 30, D-38106 Braunschweig, Germany.
Org Lett. 2000 Dec 14;2(25):4111-3. doi: 10.1021/ol006780y.
A CD(3) group close in space to (but many bonds distant from) a carbon atom A causes a substituent effect on the chemical shift of C(A) that is algebraically smaller than the effect of a CH(3) group, in agreement with the notion of shorter C-D relative to C-H bonds. Hence, the deuterium isotope effect of CD(3) upon delta(C(A)) is shielding when the substituent effect is deshielding, and vice versa.
与碳原子A在空间上接近（但相隔多个键）的CD(3)基团对C(A)化学位移产生的取代基效应，在代数上小于CH(3)基团的效应，这与C-D键相对于C-H键更短的概念相符。因此，当取代基效应为去屏蔽时，CD(3)对δ(C(A))的氘同位素效应为屏蔽，反之亦然。
