Ch. 4 - Alkanes and CycloalkanesWorksheetSee all chapters
All Chapters
Ch. 1 - A Review of General Chemistry
Ch. 2 - Molecular Representations
Ch. 3 - Acids and Bases
Ch. 4 - Alkanes and Cycloalkanes
Ch. 5 - Chirality
Ch. 6 - Thermodynamics and Kinetics
Ch. 7 - Substitution Reactions
Ch. 8 - Elimination Reactions
Ch. 9 - Alkenes and Alkynes
Ch. 10 - Addition Reactions
Ch. 11 - Radical Reactions
Ch. 12 - Alcohols, Ethers, Epoxides and Thiols
Ch. 13 - Alcohols and Carbonyl Compounds
Ch. 14 - Synthetic Techniques
Ch. 15 - Analytical Techniques: IR, NMR, Mass Spect
Ch. 16 - Conjugated Systems
Ch. 17 - Aromaticity
Ch. 18 - Reactions of Aromatics: EAS and Beyond
Ch. 19 - Aldehydes and Ketones: Nucleophilic Addition
Ch. 20 - Carboxylic Acid Derivatives: NAS
Ch. 21 - Enolate Chemistry: Reactions at the Alpha-Carbon
Ch. 22 - Condensation Chemistry
Ch. 23 - Amines
Ch. 24 - Carbohydrates
Ch. 25 - Phenols
Ch. 26 - Amino Acids, Peptides, and Proteins

When alkanes contain double or triple bonds, that totally changes the way we name the molecule. 

Concept #1: How to name alkenes and alkynes 

Transcript

Let's go ahead and add a few more functional groups, so now we're going to talk about aklenes, alkynes, and alcohols.
So first let's start off with the pi bonds, with the double bonds and the triple bonds. Alkenes and alkynes are going to be named by adding a modifier. So this is going to be the very first time that we're using a modifier in an IUPAC name, so I'm going to teach you guys how to do this.
What that means is that instead of using the ending -ane, like we always use. It stands for alkane. Instead of using that ending we're going to use, we're going to modify it to either be -ene if it's an alkene or -yne if it's an alkyne. That's why we call it a modifier. It modifies the root name. So now all of the sudden, a hexane becomes a hexyne if it has a triple bond in it. Does that make sense? Cool.
So then let's talk about some important rules here. Alkenes and alkynes are actually going to receive priority in numbering alkanes. This is also going to be the very first time that now when it comes to numbering the chain, we are going to give priority to this group. What that means is that I don't care about the closest substituent, all I care about now is how do I give my double bond or my triple bond the lowest number possible. Isn't that interesting? So now I'm just saying how can I make that number as low as possible. That's all I care about.
Then, finally, this can get tricky because these double bonds go over two carbons, so sometimes it can be tricky what's the location. Is it the first carbon or the second carbon? The location is always assigned to the first double-bonded carbon or triple-bonded carbon.
So what I want to do here is I want to go ahead and name this compound. I want you guys to go ahead and try it first with the rules and then I'll go ahead and I'll give you the name.

Alkenes and alkynes are named as modifiers, meaning we add suffix modifiers to the root chain: 

Double and triple bonds get priority, so try to give them the smallest number possible. 

Example #1: Name the following compound 

(You may see alcohols at the end of the video above. If it is included in your textbook, the videos will be in the corresponding chapter).

 

To find it quickly, just type "Naming Alcohols" in the searchbar at the top of the page :).

 

Nice job, guys! Let's move on to the next topic. 

Which of the following is the correct IUPAC name for the following compound?a) 4-ethyl-1,3-dimethyl-3-penteneb) 2-ethyl-1,1,3-trimethylbutenec) 3-ethyl-2,4-dimethyl-2-pentened) 2,4-dimethylhexene
The general molecular formula for alkanes is  CnH2n+2. What is the general molecular formula for: (b) Alkenes 
The IUPAC name for the following molecule isA)        2,4-dimethyl-5-hexeneB)        3,5,5-triethyl-1-penteneC)        3,5-dimethyl-1-hexene
There are three constitutional isomers of the molecular formula C6H10 that are internal alkynes. Draw them and name them.
Provide a name for the following pure compound. Be sure to name stereoisomers properly, designating configurations when necessary.
Name the following cycloalkenes using systematic names.
Select the correct name for the following compound, including the correct (E) or (Z) designation where appropriate.a. (E)-4-ethyl-4-methyl-2-hexyneb. (Z)-4-ethyl-4-methyl-2-hexynec. 3-ethyl-3-methyl-2-hexyned. 4-ethyl-4-methyl-2-hexyne
Provide the missing information (structure, IUPAC name, or substituents) and also indicate the stereochemistry where necessary (i.e. cis, trans)
Name the following molecule (using IUPAC nomenclature):
Provide a systematic IUPAC name for the molecule below. Remember to include the absolute configuration (R/S) of all the chirality centers in the molecule.
Name the following alkenes using systematic names. 
Write structural formulas for each of the following:(a) 1-Heptene
Write structural formulas for each of the following:(b) 3-Ethyl-2-pentene
Name the following alkene using systematic names.
Write structural formulas for each of the following:(g) 1-Bromo-3-methylcyclohexene
Name the following alkenes using systematic names.
Write structural formulas for each of the following:(h) 1-Bromo-6-methylcyclohexene
Write structural formulas for each of the following:(j) Vinylcycloheptane
Name the following alkenes using systematic names.
Write a structural formula and give two acceptable IUPAC names for each alkene of molecular formula C7H14 that has a tetrasubstituted double bond.
Name the following alkenes using systematic names.
Give an IUPAC name for each of the following compounds:
Name the compound given below.
Give an IUPAC name for each of the following compounds:
Give an IUPAC name for each of the following compounds:
Give an IUPAC name for each of the following compounds:
Give an IUPAC name for each of the following compounds:
Give an IUPAC name for each of the following compounds:
(a) A hydrocarbon isolated from fish oil and from plankton was identified as  2,6,10,14-tetramethyl-2-pentadecene. Write its structure.
There are 3 different possible structures (known as isomers) for a dibromoethene molecule, C2H2Br2. One of them has no net dipole moment, but the other two do. Draw a structure for each isomer. Include H atoms.
Name the following alkene. 
Name the following alkene.
What is the systematic name of this compound?a) 2-isobutyl-3-mehtylhex-5-eneb) 5-isobutyl-4-mehtylhex-1-enec) 4,5,7-trimethyloct-1-ened) 2,4,5-trimethyloct-7-ene
Give the IUPAC name for the following molecule:a) 2-chloro-1,4-dimethylcyclohex-4-eneb) 1-chloro-3,6-dimethylcyclohex-3-enec) 3-chloro-2,4-dimethylcyclohexened) 5-chloro-1,4-dimethylcyclohexene
Convert the following IUPAC names into structures:(2Z,5E)-5-isopropylocta-2,5-diene
Convert the following alkene to IUPAC name:
Name the structure below according to IUPAC nomenclature rules. If stereochemistry is indicated in the structure, denote the correct stereochemistry in the name.
Draw the structure of 1,3-dichloro-2-butene.
Provide an IUPAC name for each of the compounds shown. (Specify (E)/(Z) stereochemistry, if relevant, for straight chain alkenes only. Pay attention to commas, dashes, etc.) 
Name the following alkenes using systematic names. 
What is the IUPAC name of the substance shown in the following line drawing
The molecule pictured below is name:a. cis-2-ethyl-3-octeneb. trans-1-ethyl-1-octenec. trans-5-ethyl-6-octened. cis-4-ethyl-2-octenee. 3-methy-2-heptane 
Choose the correct IUPAC name of the molecule shown below: 1) trans-4-ethyl-5-propyl-4-octene2) cis-4-ethyl-5-propyl-4-octene3) trans-4-propyl-5-ethyl-4-octene 4) 4-ethyl-5-propyl-4-octene 5) none of the above 
Provide the most correct IUPAC name for the compound drawn below. Be sure to use commas and hyphens properly.
Spell out the full name of the compound.  
Name the following alkenes using systematic names.
Provide an IUPAC name for the following compound
Provide the I.U.P.A.C. name of the following compound: a. 1, 1, 2-trimethylethene b. 2-methylbuta-2-ene c. 1, 2-dimethylprpene d. 2-methyl-2-butene
Spell out the full name of the compound.
Give the IUPAC name of the product that would form when the following cycloalkene
Write the IUPAC name for the compound below. Be sure to use correct punctuation. The IUPAC name is 
Spell out the full name of the compound. 
Which of the following is the correct IUPAC name for the following compound?a. 3-bromo-1,5-cyclohexadieneb. 2-bromo-1,4-cyclohexadinec. 6-bromo-1,3-cyclohexadiened. 5-bromo-1,3-cyclohexadiene  
Provide an IUPAC name for the following compound. 
Spell out the full name of the compound.  
What is the correct name for the compound shown in the attached image?a. 3-phenyl-2-propeneb. 1-phenyl-2-propenec. 3-phenyl-1-propened. 1-phenyl-1-propene  
Write the IUPAC name for the compound below. Be sure to use correct punctuation.
Spell out the full name of the compound.