6. For each of the following molecules: i) Fill in all the C-H bonds; ii) Then identify FOUR unlque stretching frequencies that will appear in the IR spectrum in the region 1600-4000 cm' ; and predfet the position (cm-1), shape and intensity of each band. a) C=C-C-H b) CミC-C-c-c c) c-c-c-と-CEN

2. Which C4H,Br isomers give rise to the two spectra shown below? b. 8 C. 8 7 7 6 5 5 34 4 8 (ppm) 33 32 PPM 4 8 (ppm) 2H t I 2H d 3 ند 3 2H 2H quint sext NH 2 1H m 2 6H d I C 3H 1.0 PPM 0 0

A) alcohol B) alkane C) alkene D) alkyne 4000 3000 2000 1500 1000 500 E) aldehyde An IR spectrum of an unknown compound is shown below. Predict the primary structural feature present in this compound.

Please provide the C13NMR spectra for the following compounds:

ii,iii,iv

2. (2) In proton NMR, hydrogens with environments which have the lowest electron density are found a) upfield c) downfield b) are unobservable d) can be anywhere in the spectrum 3. (1) How many signals (peaks) are found for the H atom on the tertiary carbon of 2-methylpropane, due to spin-spin splitting? a) 1 b) 2 c) 4 d) 8 e) 10

11

2. Draw a molecule with the molecular formula C3H100 that would have the following peak(s) in its IR spectrum. (all major non-fingerprint absorbances are listed) а. 2900-3000 cm-1 2750 and 2850 cm- 1725 cm- nothing above 3000 cm' -1

Estimate the chemical shifts on the following hydrogens. H (CH3)3C. H CH3- (a) (b) H C(CH3)3 CH₂ (d) CH3-C-C=C-H | OH (e) CH₂ CH₂ CH₂CH₂-C-OH CH₂ H o CH₂

10. Predict the number of signals expected (disregarding splitting) in the 1H spectrum of а. OH b. .CI HO