CHEM 2020 Chapter Notes - Chapter 13: Geminal, Ethyl Group, Alkyne
17 Sep 2013
School
Department
Course
Professor
Document Summary
There are three types of protons in a-xylene, but only two absorptions are seen in the spectrum. The aromatic protons hb and he are accidentally equivalent, producing a broadened peak at 07. 1. The area under the blue line is corresponding to the number of protons. A proton in the nmr spectrometer is subjected to both the external magnetic field and the induced field of the shielding electrons. This splitting of signals into multiplets, called spin-spin splitting, results when two different types of protons are close enough that their magnetic fields influence each other. Such protons are said to be magnetically coupled. Splitting of the - ch2br group in 1 , 1 ,2-tribromoethane. When the nearby ha proton is aligned with the external magnetic field, it deshields hb; when ha is aligned against the field, it shields hb. The ethyl group appears as a triplet at 81. 2 ( - ch3) and a quartet at 82. 6 (-ch2 - ) .
