Concept explainers
Explain why each name is incorrect and then write a correct name. Strategy: First draw the structural formula suggested by the incorrect name. Then identify the error, for example, failure to locate the longest chain that contains the
(a) 1-Methylpropene (b) 3-Pentene
(c) 2-Methylcyclohexene (d) 3,3-Dimethylpentene
(e) 4-Hexyne
(f) 2-lsopropyl-2-butene
(a)
Interpretation:
To analyse the error and write the correct IUPAC names.
Concept Introduction:
The rules to write the IUPAC names are as follows-
- The longest carbon chain is identified, and the root name is given accordingly.
- All the substituents attached to the root chain are determined.
- The position of the substituents is so assigned that the sum of their positions comes to be the least of all possible positions.
- The prefix di, tri, tetra is used if the same substituent is present two, three and four times respectively.
- All the substituents in the name are written in alphabetical order.
- For a cyclic hydrocarbon the prefix cyclo- is used.
Answer to Problem 16P
But-2-ene.
Explanation of Solution
1-Methylpropene.
Error- longest chain not correctly located.
Correct name-
But-2-ene.
But-2-ene.
(b)
Interpretation:
To analyse the error and write the correct IUPAC names.
Concept Introduction:
The rules to write the IUPAC names are as follows-
- The longest carbon chain is identified, and the root name is given accordingly.
- All the substituents attached to the root chain are determined.
- The position of the substituents is so assigned that the sum of their positions comes to be the least of all possible positions.
- The prefix di, tri, tetra is used if the same substituent is present two, three and four times respectively.
- All the substituents in the name are written in alphabetical order.
- For a cyclic hydrocarbon the prefix cyclo- is used.
Answer to Problem 16P
2-pentene.
Explanation of Solution
3-Pentene.
Error- Position of double bond not mentioned correctly.
Correct name-
2-Pentene.
(c)
Interpretation:
To analyse the error and write the correct IUPAC names.
Concept Introduction:
The rules to write the IUPAC names are as follows-
- The longest carbon chain is identified, and the root name is given accordingly.
- All the substituents attached to the root chain are determined.
- The position of the substituents is so assigned that the sum of their positions comes to be the least of all possible positions.
- The prefix di, tri, tetra is used if the same substituent is present two, three and four times respectively.
- All the substituents in the name are written in alphabetical order.
- For a cyclic hydrocarbon the prefix cyclo- is used.
Answer to Problem 16P
1-Methylcyclo-1-hexene.
Explanation of Solution
2-Methylcyclohexene.
Error- Position of methyl not correct.
Correct name-
1-Methylcyclo-1-hexene.
(d)
Interpretation:
To analyse the error and write the correct IUPAC names.
Concept Introduction:
The rules to write the IUPAC names are as follows-
- The longest carbon chain is identified, and the root name is given accordingly.
- All the substituents attached to the root chain are determined.
- The position of the substituents is so assigned that the sum of their positions comes to be the least of all possible positions.
- The prefix di, tri, tetra is used if the same substituent is present two, three and four times respectively.
- All the substituents in the name are written in alphabetical order.
- For a cyclic hydrocarbon the prefix cyclo- is used.
Answer to Problem 16P
3,3-Dimethyl-1-pentene.
Explanation of Solution
3,3-Dimethylpentene.
Error-position of double bond not mentioned.
Correct name-
3,3-Dimethyl-1-pentene.
(e)
Interpretation:
To analyse the error and write the correct IUPAC names.
Concept Introduction:
The rules to write the IUPAC names are as follows-
- The longest carbon chain is identified, and the root name is given accordingly.
- All the substituents attached to the root chain are determined.
- The position of the substituents is so assigned that the sum of their positions comes to be the least of all possible positions.
- The prefix di, tri, tetra is used if the same substituent is present two, three and four times respectively.
- All the substituents in the name are written in alphabetical order.
- For a cyclic hydrocarbon the prefix cyclo- is used.
Answer to Problem 16P
2-Hexyne.
Explanation of Solution
4-Hexyne.
Error- position of triple bond is incorrectly mentioned.
Correct name 2-Hexyne.
(f)
Interpretation:
To analyse the error and write the correct IUPAC names.
Concept Introduction:
The rules to write the IUPAC names are as follows-
- The longest carbon chain is identified, and the root name is given accordingly.
- All the substituents attached to the root chain are determined.
- The position of the substituents is so assigned that the sum of their positions comes to be the least of all possible positions.
- The prefix di, tri, tetra is used if the same substituent is present two, three and four times respectively.
- All the substituents in the name are written in alphabetical order.
- For a cyclic hydrocarbon the prefix cyclo- is used.
Answer to Problem 16P
3,4-Dimethyl-2-pentene.
Explanation of Solution
2-Isopropyl-2-butene.
Error- longest chain is not correctly located.
The correct name will be-
3,4-Dimethyl-2-pentene.
Want to see more full solutions like this?
Chapter 12 Solutions
Introduction To General, Organic, And Biochemistry
- Question 1 One of these alkenes shows cis-trans isomerism. Draw structural formulas for both isomers. Note: All structures should be drawn with no bonds between carbon and hydrogen. (a) 1-Pentene (b) 2-Pentene (c) 3-Ethyl-2-pentene (d) 2,3-Dimethyl-2-pentene (e) 2-Methyl-2-pentene (f) 2,4-Dimethyl-2-pentene X Incorrect. Draw the cis isomer of the alkene. H;C. CH3 Edit H H. X Incorrect. Draw the trans isomer of the alkene. H;C. Edit Hi `CH3arrow_forwardDraw the structural formula of (Z)-3-methyl-2- heptene. Please draw it outarrow_forward2)What is the correct name of the following molecule? a) 3,5-difluoroanisole b) Difluoromethoxybenzene c) 1,5-difluoro-3-methoxybenzene d) 1,3-difluoro-5-methyl-O-benzenearrow_forward
- For the following, you must draw an appropriate structure that has the chemical formula C5H,NO with the indicated functional group(s) and/or property. In each case, identify any other functional groups in the molecule you draw, that were not indicated in the question. You may use condensed dash or bond-line structure to draw your molecules. a) An aldehyde b) A cyclic ether c) An acyclic amide that cannot form hydrogen bonds with itselfarrow_forwardQuestion 2arrow_forwardDraw structures for the following molecules. (a) 2-iodo-2,3-dimethylheptane (b) 4-cyclopropyl-3-ethyl-2-methyloctane (c) 1-ethyl-2,4-dimethylcyclopentanearrow_forward
- Each of the following names is wrong. Draw structuresbased on them, and correct the names:(a) 4-methylhexane(b) 2-ethylpentane(c) 2-methylcyclohexane(d) 3,3-methyl-4-ethyloctanearrow_forwardDraw line structures for the following alkenes. Which can exist as cis–trans isomers? For those that can, draw both isomers.(a) 2-Methyloct-2-ene (b) Hept-3-ene(c) 3,4-Dimethylhex-3-enearrow_forwardThe following names are incorrect. Draw the structure that is represented by the name, then name it correctly. a) 2-isopropyl butane b) 5-(1,3-dimethyl butyl)-6-ethyl decane c) (4-cyclobutyl pentyl) cyclohexane d) 1-chloro-2-ethyl-4-cyclopentanol e) 4-(2-ethyl butyl)-3-methyl-6-propyl nonanearrow_forward
- Answer the following: 1) A student observes a squiggly line for a while before telling another student that the molecule is 3,4,5-trimethylpentane. Is the student correct and, if not, what is the correct name of the molecule? a)They’re correct b)They’re incorrect. 2,3,4-trimethylpentane. c)They’re incorrect. 3,4-dimethylpentane. d)They’re incorrect. 3,4-dimethylhexane. 2) A student is interpretting Organic Chemical heiroglyphics and decides that the molecule must be “1,1-dimethylsomethingsomething”. Ignoring how clearly wrong the second part is, is “1,1-dimethyl” valid and, if not, why does it not work?a)It’s valid b)It’s not valid, there is no need to include “di” in front of methyl c)It’s not valid, there is no need to include the numbers. d)It’s not valid, having a methyl on Carbon-1 would just increase the length of the parent chain. 3) A student is looking at a hexagon that a teacher is swearing is a molecule. It’s a friggin’ square. What is something he knows must be part of the…arrow_forwardDo not write it out free handed. Please ensure it legible.arrow_forwardDraw the structures of the following compounds. (a) 1-chloro-1 isopropylcyclopentanearrow_forward
- Chemistry: The Molecular ScienceChemistryISBN:9781285199047Author:John W. Moore, Conrad L. StanitskiPublisher:Cengage Learning