Why Is the Correct Name 3-Methyl-3-Propylheptane?

  • Thread starter Thread starter toothpaste666
  • Start date Start date
  • Tags Tags
    Hydrocarbon
Click For Summary

Discussion Overview

The discussion revolves around the naming of a chemical compound, specifically why the correct name is 3-Methyl-3-Propylheptane. Participants explore the principles of IUPAC nomenclature, focusing on identifying the longest carbon chain and the implications of branching in the structure.

Discussion Character

  • Homework-related
  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant asserts that the longest chain has 7 carbons and proposes the name 3-methyl-3-propylheptane based on this count.
  • Another participant questions the comparison between chains of 7 and 8 carbons, implying that the longest chain should be prioritized.
  • A different participant expresses confusion about the presence of three chains, suggesting a need for clarification on the structure.
  • One participant argues against an alternative name (E), stating it incorrectly suggests an octane chain when a heptane structure is present.
  • Another participant admits uncertainty about where an octane chain could be identified in the structure.
  • A comment highlights that "longest chain" does not necessarily refer to a straight line, suggesting a more nuanced understanding of chain selection.
  • A later reply provides a directional approach to identifying the longest chain by suggesting a method of counting from the leftmost carbon and turning at the branching point.
  • One participant expresses gratitude for the clarification, indicating a shift in understanding.

Areas of Agreement / Disagreement

Participants exhibit a mix of agreement and confusion regarding the identification of the longest chain and the correct nomenclature. Multiple competing views remain, particularly concerning the interpretation of chain length and structure.

Contextual Notes

There are unresolved assumptions about the structural representation of the compound, particularly regarding the identification of the longest chain and the implications of branching. The discussion does not resolve the question of whether an octane chain is present.

toothpaste666
Messages
517
Reaction score
20

Homework Statement


chemproblem.png

The Attempt at a Solution


The answer is supposedly C but I can't figure out why its not E.
first I count the number of C in the longest chain. There are 7 C and there are only single bonds so the the root and suffix is heptane. there is a chain with one C (methyl) and one with 3 C (propyl) and they are both attached the the third carbon counting from the side that gives the smallest numbers. listing in alphabetical order the name should be 3-methyl-3-propylheptane
 
Physics news on Phys.org
You have to select the longest chain. Which number is higher 7, or 8?
 
I am confused. To me it seems that there are 3 chains, one with 7, one with 3 and one with 1 carbons
 
E can't be right as it calls for HEPTane, when there is a possible OCTane chain.
 
forgive me if it is obvious but I don't see where the octane chain could be
 
"Longest chain" doesn't necessarily mean longest straight line.
 
  • Like
Likes   Reactions: toothpaste666
Start from the leftmost carbon, turn right (down) at the ternary carbon.
 
  • Like
Likes   Reactions: toothpaste666
ahh i get it now. thanks guys
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 1 ·
Replies
1
Views
15K
Replies
10
Views
2K
Replies
4
Views
3K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 1 ·
Replies
1
Views
7K
Replies
2
Views
3K
  • · Replies 4 ·
Replies
4
Views
4K