Spectral Problems Instructions 1 Identify The Compounds For Each Group Of Spectra Mass Proton Carbon And Ir 2 Ass 1 (48.54 KiB) Viewed 10 times
Spectral Problems Instructions 1 Identify The Compounds For Each Group Of Spectra Mass Proton Carbon And Ir 2 Ass 2 (31.02 KiB) Viewed 10 times
Spectral Problems Instructions 1 Identify The Compounds For Each Group Of Spectra Mass Proton Carbon And Ir 2 Ass 3 (36.65 KiB) Viewed 10 times
Spectral Problems Instructions 1. Identify the compounds for each group of spectra (mass, proton, carbon and IR). 2. Assign the proton and carbon and IR spectra. Identify at least two fragmentations on the mass spectrum. HINTS ANS TIPS: 1. Finding a molecular formula using mass percentages: For element Z mass%2 therefore... #Z P = (Z x atomic wt Z) x 100% MW of compound mass Zx MW of compound atomic wt Z x 100 2. If all of the elements do not add up to 100 %, the remaining element is probably Nitrogen. 3. Odd Molecular Weights (MW) indicate the presence of an odd number of nitrogen atoms. 4. The MW can be obtained by looking at the molecular ion (MI) or by looking at the second to last peak visible in the mass spectrum. See Appendix for common fel need est apaq art fragmentations. possib 5. Units of unsaturation (# of rings and/or double bonds) may be obtained from the molecular formula in the following way: (Example: C-H₁NF-0₂) a) For the purpose of this calculation, find effective number of H. i) For each halogen, add 1 H. i) m For each nitrogen, subtract 1H. Oxygen has no effect on this calculation. So C₂H₁NF₂O, becomes C7H14 (JUST FOR THIS CALCULATION). b) Find how many H the compound would have if it were saturated (remember a saturated hydrocarbon is C₂H2n+2). C7H₁4--> C7H16 c) Units of unsaturation = Saturated H- Actual H 2 16-14 2 = 1 (ring or double bond) 6. For compounds with N, look to see if a nitro group (NO₂) is present.