three compounds A,B and C all have the formula C5H8. All three compounds will decolorize bromine in CCl4. Compound A reacts with NaNH2. Compounds A and B both yield pentane when they are treated with excess H2 with the pt catalyst. Under the same conditions C absorbs only 1 mol of H2 and gives the product C5H10. Reaction of compound B ozone at 78deg followed by Zn workup gives three different compounds, one of which is a formaldehyde. Reaction of C with ozone gives only one compound, a symmetrical dialdehyde with the formula C5H8O2. What are the structures of A,B and C?
To determine the structures of compounds A, B, and C, we need to analyze the given information and consider the reactivity and products obtained in various reactions. Let's break down the information step by step:
1. All three compounds have the formula C5H8. This means they contain five carbon atoms and eight hydrogen atoms.
2. All three compounds decolorize bromine in CCl4. This implies that they have unsaturated bonds (double or triple bonds), which react with bromine, causing the solution to lose its characteristic brown color.
3. Compound A reacts with NaNH2. This reaction suggests that compound A contains an acidic hydrogen atom (capable of being deprotonated by NaNH2).
4. Compounds A and B yield pentane when treated with excess H2 in the presence of a platinum (pt) catalyst. This reaction indicates that both A and B have double bonds, which are saturated (reduced) to form pentane.
5. Under the same conditions as above, compound C absorbs only 1 mol of H2 and gives the product C5H10. This suggests that compound C has either a triple bond or two double bonds, resulting in a partial reduction to C5H10.
6. Reaction of compound B with ozone (O3) at 78°C followed by Zn workup gives three different compounds, one of which is formaldehyde (H2C=O). This indicates that compound B has an alkene (double bond) that undergoes ozonolysis, yielding different products, including formaldehyde.
7. Reaction of compound C with ozone gives only one compound, a symmetrical dialdehyde with the formula C5H8O2. This implies that compound C has two double bonds, which undergo ozonolysis to produce the symmetrical dialdehyde.
Based on this information, we can deduce the structures of compounds A, B, and C as follows:
A: Compound A has a formula of C5H8, reacts with NaNH2, and is reduced to pentane. Therefore, A must have a double bond and an acidic hydrogen atom. One possible structure is 1-pentene (CH2=CH-CH2-CH2-CH3).
B: Compound B has a formula of C5H8, reacts with ozone to yield formaldehyde, and forms pentane when reduced with H2. B must contain an alkene that undergoes ozonolysis, producing formaldehyde. One possible structure is 2-methyl-2-butene (CH3-C(=CH2)-CH(CH3)-CH3).
C: Compound C has a formula of C5H8, absorbs only 1 mol of H2 to form C5H10, and yields a symmetrical dialdehyde when reacted with ozone. This indicates that C contains two double bonds and undergoes ozonolysis, producing a symmetrical dialdehyde. One possible structure is 1,2-pentadiene (CH2=CH-CH2-CH=CH2).
Please note that these are one possible set of structures for compounds A, B, and C based on the given information. Other isomers may also fulfill these criteria.