「パラ置換プロピルベンゼン(a)、2-メチルプロピルベンゼン(b)及び2,2-ジメチルプロピルベンゼン(c)の側鎖炭素化学シフトにおける置換基効果について」

The substituent-induced chemical shifts (SCS) for the side chain carbons in a number of the para substituted propylbenzenes (A), 2-methylpropylbenzenes (B), and 2, 2-dimethylpropylbenzenes (C) were determined. The SCS of C_2 (β-position to the ring) of A showed clearly an inverse trend in the sense of the substituent electronic effect as good as SCS (^<13>CH_3) of p-substituted ethylbenzenes. SCS (C_2) of B for electron attracting groups by resonance exhibited also an inverse trend while the magnitudes were very small. SCS (C_2) of C showed a normal trend. It was confirmed that the most important factor for the inversed SCS for SCS (C_2) for the ethylbenzenes, A, and B was the polarization of the C_2-H bond induced by the substituted phenyl moiety.