A saturated open-chain amine has the formula C₅H₁₃N…
Contributed by StemPy LabTry it on paper first. A hint, the key idea and the worked solution are here when you need them.
A saturated open-chain amine has the formula . Count its structural isomers class by class. A primary amine is one pentyl group on the nitrogen. A secondary amine is two alkyl groups with five carbon atoms between them. A tertiary amine is three alkyl groups with five carbon atoms among them. Use the numbers of alkyl groups: 1, 1, 2, 4 and 8 for one to five carbon atoms. Give the number of primary, secondary and tertiary amines, and the total.
Need a reminder? The key ideaShow
The class of an amine is the number of carbon groups on the nitrogen atom: one, two or three. An aromatic amine has the nitrogen joined straight to a benzene ring. A saturated amine with carbon atoms is . Count isomers by choosing alkyl groups: there are 1, 1, 2, 4, 8 and 17 different alkyl groups with 1 to 6 carbon atoms.
The worked solution
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. Primary. There are 8 pentyl groups, so 8 primary amines.
Step 2. Secondary. The split 1 + 4: one methyl group and any of 4 butyl groups, . The split 2 + 3: one ethyl group and any of 2 propyl groups, . The total is .
Step 3. Tertiary. The split 1 + 1 + 3: two methyl groups and one of 2 propyl groups, . The split 1 + 2 + 2: one methyl and two ethyl groups, . The total is .
Step 4. All. .
Answer: 8, 6, 3 and 17 in all.
Check. The lesson gave 8 for . One more carbon roughly doubles the count, and 17 fits.
Discussion (0)
Log in to join the discussion.
Loading…