og (ppm from M5) Question 3. (8 Marks) i. Match the IR values in column B with the structure in column A. (2 Marks) A B OH i. 1680 cm 3500-3300 cm 1. cyclohex-3-enol ii. 1730 cm 2200 cm1 2. pent-4-yn-2-one 3. ii. 1720 cm 2125 cm N 4-formylcyclohexanecarbonitrile iv 4. 1600 cm 3300 cm 1 N-methylacetamide ii. For each of the given compounds, determine whether the two protons shown in red are homotopic, enantiotopic, or diastereotopic. (3 Marks) H. CH, ' Br NH2 H , H HH .CO2H "H H2N iii. Encircle/write the auxochromes in the given structure. (1 Mark) OH OH SO Na iv. Encircle/write the chromophore in the given structure. (1 mark) NH2 Bordado CI v. With the help of arrows show the possible homonuclear/hetronuclear NOE in the given structures. (1 mark) ok B D Question 4. (4 + 4 = 8 Marks) A. Why tetramethylsilane (TMS) is used as solvent in NMR