Determine what this molecule should really be named.
2,2-ethylpent-3-ene
I get the answer 2,2-diethylpent-3-ene. Why would the answer be:
4-ethyl-4-methylhex-2-ene
If you draw it out as a 2,2-diethylpent-3-ene but show one of the ethyl groups as -CH2CH3 instead of C2H5, it adds another C to make the longest chain a hexene. From there you add the substituents.
A chemist ran the reaction and obtained 5.80 g of ethyl butyrate. What was the percent yield?
The correct name for the given molecule, 2,2-ethylpent-3-ene, would actually be 4-ethyl-4-methylhex-2-ene.
Let's break it down step-by-step:
1. Identify the longest continuous chain of carbon atoms: In this case, it is a six-carbon chain.
2. Number the carbon atoms in the chain to give the substituents the lowest possible numbers: Start numbering from the end that gives the substituents the lowest numbers. In this case, if we start numbering from the left, the ethyl group would be on carbon 2, and the methyl group would be on carbon 3.
3. Name and locate the substituents: The molecule has two substituents - an ethyl group and a methyl group. The ethyl group is on carbon 4, and the methyl group is on carbon 4 as well.
4. Write the substituents and their corresponding positions as prefixes: The substituents are a 4-ethyl group and a 4-methyl group.
5. Complete the name by adding the name of the main chain with the double bond: The main chain is a hex (6) carbon chain with a double bond between carbon 2 and carbon 3, so the main chain is called hex-2-ene.
Putting it all together, the correct name for the molecule is 4-ethyl-4-methylhex-2-ene.
To determine the correct name of a molecule, you must follow the guidelines of organic nomenclature. Let's break down the steps to arrive at the correct name.
1. Identify the longest carbon chain: In this case, we have a 7-carbon chain.
2. Number the chain: Begin numbering from one end to the other, choosing the direction that will give the substituents the lowest possible numbers. In this case, numbering from left to right would be appropriate.
3. Locate and name the substituents: We have two substituents on the second carbon. One is an ethyl group (C2H5) and the other is a methyl group (CH3).
4. Assign the locants: The locant is the number in front of the substituent name indicating its position on the main carbon chain. In this case, we have a 2,2-disubstituted compound.
Based on these steps, the correct name for the molecule should be 2,2-diethylpent-3-ene.
However, the alternative name you mentioned, 4-ethyl-4-methylhex-2-ene, is also correct. This name is obtained by numbering the chain in the opposite direction (from right to left), which gives higher locants to the substituents.
Both names are acceptable according to the IUPAC nomenclature rules, as they accurately describe the structure of the molecule. The choice between the two names depends on the specific context or convention being followed.