Location of Signals TABLE 13-2 Chemical Shifts of the Chloromethanes More electronegative Chemical Compound Shif Difference atoms deshield more and S0.2 give larger shift values. 2.8 ppm Effect decreases with 53n distance. 2.3 ppm Additional electronegative 65.3 atoms cause increase in 1.9 ppm 87.2 chemical shift. => Note:Each chlorine atom added changes the chemical shift of the remaining methyl protons by about 2 to 3 ppm.These changes are nearly additive. Chapter 13 16Chapter 13 16 Location of Signals • More electronegative atoms deshield more and give larger shift values. • Effect decreases with distance. • Additional electronegative atoms cause increase in chemical shift. =>