A correlation between .beta.-hydrogen isotope effects on carbon-13 NMR chemical shifts in unsaturated systems and the strength of hyperconjugative interactions
作者:Cheryl H. Arrowsmith、A. Jerry. Kresge
DOI:10.1021/ja00285a006
日期:1986.12
..beta..-Hydrogen isotope effects on the carbon-13 NMR chemicalshifts of the trigonal carbon in CL/sub 3/C(R)=X (L = H or D) are reported for 15 substances in which the positive charge density at the trigonal carbon is regulated through systematic variation of R and X. A linear relationship is found between these isotope effects and the chemicalshifts of the trigonal carbons, and this is taken as
..β..-氢同位素对 CL/sub 3/C(R)=X(L = H 或 D)中三角碳的碳 13 NMR 化学位移的影响报告了 15 种物质,其中正电荷三方碳的密度通过 R 和 X 的系统变化来调节。在这些同位素效应和三方碳的化学位移之间发现了线性关系,这被视为这些同位素效应的大小依赖于CL/sub 3/ 和 C(R)=X 之间超共轭相互作用的强度。提出了根据非谐碳氢键弯曲振动对超共轭 NMR 同位素效应的解释。
PINKUS A. G.; SABESAN A.; SUBRAMANYAM R., J. LABELLED COMPOUNDS AND RADIOPHARM., 1981, 18, NO 3, 439-443