Reference no: EM13132377

Lab(5) establish a structure
1. A colorless liquid A (C3H6O) was soluble in water and ether, and had a boiling point of 94-96 degrees C. it decolorized a Br2-CH2Cl2 solution and gave a positive ceric nitrate test. On catalytic hydrogenation it formed Compound B (C3H8O), which did not decolorized the above bromine solution, but did give a positive ceric nitrate test. Treatment of Compound A with ozone, followed by hydrolysis in the presence of zinc, gave formaldehyde as one of the products. Compound A formed an alpha-naphthylurethane with a melting point of 190 degrees C. what are the names and structures of Compounds A and B?

2. A compound of formula C14H12 gave a positive Baeyer test and burned with a yellow, sooty flame. Treatment with ozone followed by hydrolysis in the presence of zinc gave formaldehyde as one of the products. Also isolated from the ozonolysis reaction was a second compound, C13H10O, which burned with a yellow, sooty flame, and readily formed a semicarbazone with a melting point of 164 degrees C. The 1H NMR spectrum of this compound (C13H10) showed only complex multiplets near 7.5 ppm; the fully 1H-decoupled 13C NMR spectrum showed only 5 peaks. What are the structures and names of the two compounds?

3. Compound A (C7H14O) burned with a yellow, nonsooty flame and did not decolorized a bromine-methylene chloride solution. It did give a positive 2,4- dinitrophenylhydrazine test, but a negative Tollens test. Treatment of the compound with lithium aluminum hydride followed by neutralization with acid, produced a Compound B, which gave a positive Lucas test in about 5 min. Compound B also gave a positive ceric nitrate test. The 1H NMR spectrum for Compound A gave the following data:

1.02 ppm 9H, singlet
2.11 ppm 3H, singlet
2.31 ppm 2H, singlet.

Give suitable structures for Compounds A and B.

4. A friend of yours who is a graduate student attempting to establish the structure of a chemical species from field clover, isolated an alcohol that was found to have an optical rotation of +49.5 degrees. Chemical analysis gave a molecular formula of C5H10O. It was also observed that this alcohol readily decolorized Br2-CH2Cl2 solution. On this basis, the alcohol was subjected to catalytic hydrogenation and was found to absorb 1 mol of hydrogen gas. The product of the reduction gave a positive ceric nitrate test, indicating that it too was an alcohol. However, the reduced compound was optically inactive. Your friend has come to you for assistance in determining the structures of the two alcohols. What do you believe the structures are?