The following names are incorrect. Tell what is wrong with eac...

Question

The following names are incorrect. Tell what is wrong with each, and provide the correct names.

a. Incorrect structure for 2,2-Methylpentane; correct name should reflect proper alkane naming conventions.

Accepted Answer

All right. Hi, everyone. So this question says is the following alkene incorrectly named. If yes, what is its correct name? Explain option A says it is correctly named because it takes into account the correct prefix and position of the substituents as well as the correct name of the parent chain or it is incorrectly named because B it does not include the prefix of the substituents. Its correct name is 33 dimethyl hexane. C. The substituents are assigned the wrong position. Its correct name is 22 methyl hexane or D. It provided the wrong name of the parry chain. Its correct name is 33 methyl heptane. So now let me scroll up one more time. So you can see the whole arcane and the proposed name which is 33 methyl hexane. Now, the first step if you recall is to always find the parent chain and number it accordingly, recall that the parent chain is the longest continuous chain of carbons present in the molecule and examining the structure, given the longest continuous chain goes across the structure itself. And by counting the number of carbons along this chain, I get that there are six carbons in total. Now when the parent chain has six carbon atoms, the parent name is going to be hexane. So the next step now is to find substituents and name them accordingly. Now when it comes to numbering the parent chain for the purpose of labeling your substituents, you should always number your parent chain so that your substituents have the smallest position number possible. In this case, I decided to number my parent chain going from left to right because I can see that the branch point where my substituent art was closer to the left than it was to the right. So in this case, I have two different substituents each with just one carpet. Therefore, both substituents are methyl groups. And recall that when there are two or more identical substituents, a prefix is necessary to indicate how many there are in the molecule itself. We can use dye, try tetra et cetera. Now, in this case, because we only have two, the appropriate prefix is going to be dye as in dye methyl. So now the conversation is or the question is to find our position numbers, right? Recall that every single substituent must have one position number. So because I have two substituents, I need to have two position numbers even if they are on the same carbon. So according to the structure here, both methyl groups are attached to carbon three of the parent chain. So my position numbers are going to be three. So that's three comma three dash dimethyl. Now the dash is there to separate numbers from letters. And so the last step is to go ahead and put everything together, all substituents must be listed in alphabetical order before the name of the parent chain with no space in between. Now, in this case, we only had one type of substituent, namely methyl groups. So there was no need to necessarily sort substituents in alphabetical order, right? So I will take the name of my substituents which was three comma three dash thy missile. And then I will add the parent name afterwards with no space in between. So that's three comma three dash dimethyl hexane and again comma separate numbers from each other and dashes separate numbers from letters. So comparing the name that we've put together to the one proposed in the question, we can see that the Alcaine was originally incorrectly named because the name here 33 methyl hexane is missing the prefix necessary to specify the number of methyl groups present in the compound. Because even though it does list two position numbers, there is no prefix die to specify that there are two metal groups. So therefore, our answer is going to be option B in the multiple choice, right? It is incorrectly named because it does not include the prefix of the substituent. Its correct name is 33 dimethyl hexane. So with that being said, thank you. So very much for watching. And I hope you found this helpful.

The following names are incorrect. Tell what is wrong with each, and provide the correct names.
a.

Key Concepts

Correct Naming Conventions

Common Errors in Naming

Contextual Relevance

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