Carbon coupling constants longer range 251

Compound Formula 2 Jcc ( z) Table 3.11 (b). Longer-Range Carbon-Carbon Coupling Constants 2JCC and 3Jqc, Data from Ref. [133 a],... 

Table 4.30. Longer-range carbon-carbon coupling constants Jqc and...

Rotational-echo double-resonance (REDOR)(75,79) is a new solid-state NMR technique which is sensitive to through-space carbon-nitrogen interactions between selectively 13C and 15N-enriched sites separated by up to 5A (20-22). The parameter directly measured in a REDOR experiment is the heteronuclear dipolar coupling constant DCN, which is in itself proportional to the inverse third power of the intemuclear distance, rCN. It is this dependence on (icn)3 which accounts both for REDOR s ability to accurately measure short distances and its insensitivity to longer-range interactions. As a technique which can probe, in detail, intermolecular interactions over a distance range of 5A, REDOR is well suited to studying the distribution of small selectively-labeled molecules in polymer delivery systems. 

Table 3.8. Longer-Range Carbon-Proton Coupling Constants in Relation to Comparable Proton-Proton Couplings.

Table 4.51. One-Bond (J and Longer-range (2J, 3J, 4J) Carbon-Phosphorus Coupling Constants of Representative Phosphines [372], Phosphonium Salts [365], Phosphine oxides [366, 372, 373], Phosphonium Ylides [365, 373], Phosphonates [368, 372], Phosphites [374], and Phosphates [375] (in Hz). 

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