Chemistry 2212 Organic Chemistry II Spring 2003Week 4: covering material through the end of Chapter 12Major concepts from this week:• Interpreting mass spectra of ethers, alcohols, and ketones• Calculating the index of hydrogen deficiency (IHD)• Infrared spectroscopy• IR absorption bands for functional groups• Interpreting infrared spectraProblem solving1. (a) An unknown compound was found on the shelf in your research lab. You sentthe sample out for elemental analysis and learned that the molecular formula wasC5H12. You also acquired a mass spectrum of the compound, which is shownbelow:Give a structure for the compound that is consistent with the mass spectrum.(b) You received a telephone call from the company who did the elemental analysis, whotold you that the original elemental analysis was incorrect. The actual molecular formulawas C4H8O. Assuming that the new formula is correct and using the same massspectrum, deduce a structure that is consistent with the mass spectrum.c) Not trusting the analysis company, you acquired an infrared spectrum of the compoundthat is shown below. What is the structure of your unknown compound? Support youranswer!2. Here are the mass and IR spectra of an unknown compound with a molecularweight of 134.5 g/mole:(a) Does the compound contain a halogen atom? If so, which halogen?b) Does the compound have a functional group containing oxygen? If so, which one?c) Assuming one oxygen and one halogen, determine the molecular formula for thecompound.d) What is the index of hydrogen deficiency (IHD) for this compound?e) BONUS – give a reasonable structure for the unknown compound.4. The IR spectrum for an unknown compound with molecular formula C4H8O isshown below. (a) Determine the IHD for this compound. (b) Give a structureconsistent with the IR
View Full Document
Unlocking...