NMR Experiment A Spectroscopy I 1 H NMR Guidelines and Tips 1 1 2 When labeling peaks don t mistake residual solvent peaks or the TMS peak for a signal peak from the sample a 1H NMR singlet at 7 26 ppm due to residual CHCl3 from CDCl3 solvent singlet at 0 ppm due to TMS 3 Chemical shifts should be reported as the center of the peak set For peaks with odd multiplicities triplet quintet etc the chemical shift is that of the middle peak For peaks with even multiplicities doublet quartet etc the chemical shift is reported as the average of the two central most peaks 4 The peak labels in the expanded regions are in hertz Hz for assigning coupling constants a The coupling constant J for a given multiplet is equal to the distance in Hz between adjacent peaks 5 Integral values are proportional to the number of hydrogens represented by a given peak 6 Use the following abbreviations for peak multiplicities For our purposes a multiplet m is a peak that cannot be assigned a simple first order splitting pattern i e not a singlet doublet triplet etc singlet s quartet q octet oct doublet d quintet quint nonet non triplet t sextet sext multiplet m H NMR peaks should be labeled using letters a b c etc starting with the peak that is the most downfield highest ppm DOU 2C 2 H N X 2 7 Degrees of unsaturation DOU is calculated as where C is the number of carbons H the number of hydrogens N the number of nitrogens and X the number of halogens 8 Work your way through the following problems and record your answers in the answer pack 1 For each of the following compounds give the number of signals resonances that you would expect to find in the 1H NMR spectrum O a 2 H OH b For each of the following compounds give the multiplicity s d t etc and the number of protons relative integrations for each type of proton indicated Be sure to give the integration value for the entire set of protons that are of the type indicated O O N H O a b 3 O cd e ghi f Give the chemical shifts multiplicities and coupling constants for each of the peaks in the 1H NMR spectrum shown below taken on a 300 MHz spectrometer 4 Use the information from question 3 to assign the chemical shift of each peak to the appropriate set of protons in the following molecule b d O Cl O a c e 5 Complete the spectroscopy data table in the answer pack using the 1H NMR NO2 spectrum shown below for the following compound 1 H NMR 300 MHz 6 Complete the spectroscopy data table in the answer pack using the 1H NMR spectrum shown below for the following compound CN NC 1 H NMR 300 MHz Complete the spectroscopy data table in the answer pack using the 1H NMR spectrum shown 7 O O below for the following compound 1 H NMR 300 MHz 8 Complete the spectroscopy data table in the answer pack using the 1H NMR spectrum shown O O O below for the following compound 1 H NMR 300 MHz 9 Complete the spectroscopy data table in the answer pack using the 1H NMR spectrum shown O OH Br below for the following compound 1 H NMR 300 MHz