Chinese Journal of Magnetic Resonance ›› 1998, Vol. 15 ›› Issue (4): 347-353.

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CARBON ATOM DISTANCE EDGE VECTOR AND 13C NMR CHEMICAL SHIFTS OF ALKANES

Cao Chenzhong1, Liu Chao1, Liu Shushen2, Li Zhiliang3   

  1. 1. Department of Chemistry, Xiangtan Teachers College, Xiangan 411100;
    2. Department of Applied Chemistry, Guilin Technology, Guilin 541004;
    3. Institute of Chemistry and Chemical Engineering, ICP, Hunan University, Changsha 410082
  • Received:1997-12-22 Revised:1998-03-30 Published:1998-08-05 Online:2018-01-13

Abstract: A set of novel atom descriptor called as Distance-Edge Vector (μ) was developed, which expressed the total information about the carbon atom disposition with respect to one another in alkanes. By taking the Distance-Edge Vector(μ) and the path counts of length three C-C bonds (P3) apart from the given carbon atom as parameters, the multiple linear regression analysis between these parameters and the 13C NMR chemical shifts of all alkanes bearing one to nine carbon atoms (64 compounds including 326 different chemical shifts for topologically nonequivalent positions in alkanes) was curried out. The obtained result was:the standard deviation S is only 0.9629ppm and the correlation coefficient R is 0.9957. Using the linear regression analysis equation, we got precision of prediction:for 83% (90% and 95%) of the shifts, the difference between the experimental and predicted values was less than 1.0ppm (1.5ppm and 2.0ppm respectively).

Key words: 13C NMR Spectrometry, Carbon atom chemical shift, Distance-Edge Vector, Path counts of length three bounds (P3), Alkanes