Question

why tms is generally used as reference for measuring chemical shift of protons​

Answer 1

Answer:

Tetramethylsilane became the established internal reference compound for 1H NMR because it has a strong, sharp resonance line from its 12 protons, with a chemical shift at low resonance frequency relative to almost all other 1H resonances. Thus, addition of TMS usually does not interfere with other resonances.