
(a)
Interpretation:
The IUPAC name for the given molecule has to be assigned including the prefix cis- or trans-.
Concept Introduction:
- The suffix –ane has to be replaced with the suffix –ene. This is used to indicate the presence of double bond.
- The longest continuous chain of carbon atoms has to be chosen that contains both carbon atoms of the double bond.
- The parent carbon chain has to be numbered in a way so that the numbering begins at the end near to the double bond. In case if the double bond is equidistant from both ends, then numbering has to be done from the end that is closer to substituents.
- The position of the double bond has to be given a single number which is lower‑numbered carbon atom that is present in the double bond.
- Suffixes like –diene, -triene, -tetrene, and so on are used when the compound contains more than one double bond.
- In case of cycloalkenes which do not have any substitution, the numbering is not needed to locate the double bond because the bond is assumed to be between the carbons 1 and 2.
- In case if substituents are present in cycloalkene, then the double‑bonded carbon
atoms are numbered 1 and 2 in a direction where the substituent gets the lower number. - If the cycloalkenes contain more than one double bond, then one double bond is assigned the numbers 1 and 2 followed by the other double bond so that the lowest number possible is given.
Structural formula where a line represent carbon‑carbon bond and the carbon atom is considered to be present in each point and the end of lines is known as Line-angle structural formula. To indicate a double bond between carbon atom, double line is used.
If stereoisomers are possible for the alkene, the stereoinformation is shown in the IUPAC name by adding prefix cis- or trans- with respect to the groups present on the same side of double bond or opposite side of double bond.
(a)

Answer to Problem 2.50EP
The IUPAC name for the given compound is chloroethene.
Explanation of Solution
Given compound is,
The longest continuous carbon chain present in the given compound is two carbon atoms. Hence, the parent
As the given compound contains a double bond, the suffix –ane is replaced by –ene. Therefore, the name obtained is ethene.
Numbering has to be given in a way that the carbon atoms present in the double bond gets the least numbering followed by least numbering to the substituents. Therefore, the name of the given compound is chloroethene. This is because both carbon atoms are identical.
In order to include the stereo information, the groups attached to the double‑bonded carbon atoms are looked into.
The carbon atom bears identical groups that are attached to the double bond. Therefore, stereoisomerism is not possible. Hence, the IUPAC name can be given as chloroethene.
IUPAC name for the given molecule is assigned.
(b)
Interpretation:
The IUPAC name for the given molecule has to be assigned including the prefix cis- or trans-.
Concept Introduction:
IUPAC nomenclature for alkene: There are about eight rules to be followed in giving IUPAC name for alkene.
- The suffix –ane has to be replaced with the suffix –ene. This is used to indicate the presence of double bond.
- The longest continuous chain of carbon atoms has to be chosen that contains both carbon atoms of the double bond.
- The parent carbon chain has to be numbered in a way so that the numbering begins at the end near to the double bond. In case if the double bond is equidistant from both ends, then numbering has to be done from the end that is closer to substituents.
- The position of the double bond has to be given a single number which is lower‑numbered carbon atom that is present in the double bond.
- Suffixes like –diene, -triene, -tetrene, and so on are used when the compound contains more than one double bond.
- In case of cycloalkenes which do not have any substitution, the numbering is not needed to locate the double bond because the bond is assumed to be between the carbons 1 and 2.
- In case if substituents are present in cycloalkene, then the double‑bonded carbon atoms are numbered 1 and 2 in a direction where the substituent gets the lower number.
- If the cycloalkenes contain more than one double bond, then one double bond is assigned the numbers 1 and 2 followed by the other double bond so that the lowest number possible is given.
Structural formula where a line represent carbon‑carbon bond and the carbon atom is considered to be present in each point and the end of lines is known as Line-angle structural formula. To indicate a double bond between carbon atom, double line is used.
If stereoisomers are possible for the alkene, the stereo information is shown in the IUPAC name by adding prefix cis- or trans- with respect to the groups present on the same side of double bond or opposite side of double bond.
(b)

Answer to Problem 2.50EP
The IUPAC name for the given compound is cis-1,2-dibromoethene.
Explanation of Solution
Given compound is,
The longest continuous carbon chain present in the given compound is two carbon atoms. Hence, the parent alkane is ethane.
As the given compound contains a double bond, the suffix –ane is replaced by –ene. Therefore, the name obtained is ethene.
Numbering has to be given in a way that the carbon atoms present in the double bond gets the least numbering. This is followed by the substituents present in the given molecule. It is found that an bromine atom is present on the second carbon atom and bromine atom is present on the first carbon atom. As the substituents are same, prefix di- is added. Therefore, the name of the given compound is 1,2-dibromoethene.
In order to include the stereo information, the groups attached to the double‑bonded carbon atoms are looked into.
The bulky groups are present on same side of the double bond. Hence, the configuration of the given molecule is cis-. Therefore, the IUPAC name can be given as cis-1,2-dibromoethene.
IUPAC name for the given molecule is assigned.
(c)
Interpretation:
The IUPAC name for the given molecule has to be assigned including the prefix cis- or trans-.
Concept Introduction:
IUPAC nomenclature for alkene: There are about eight rules to be followed in giving IUPAC name for alkene.
- The suffix –ane has to be replaced with the suffix –ene. This is used to indicate the presence of double bond.
- The longest continuous chain of carbon atoms has to be chosen that contains both carbon atoms of the double bond.
- The parent carbon chain has to be numbered in a way so that the numbering begins at the end near to the double bond. In case if the double bond is equidistant from both ends, then numbering has to be done from the end that is closer to substituents.
- The position of the double bond has to be given a single number which is lower‑numbered carbon atom that is present in the double bond.
- Suffixes like –diene, -triene, -tetrene, and so on are used when the compound contains more than one double bond.
- In case of cycloalkenes which do not have any substitution, the numbering is not needed to locate the double bond because the bond is assumed to be between the carbons 1 and 2.
- In case if substituents are present in cycloalkene, then the double‑bonded carbon atoms are numbered 1 and 2 in a direction where the substituent gets the lower number.
- If the cycloalkenes contain more than one double bond, then one double bond is assigned the numbers 1 and 2 followed by the other double bond so that the lowest number possible is given.
Structural formula where a line represent carbon‑carbon bond and the carbon atom is considered to be present in each point and the end of lines is known as Line-angle structural formula. To indicate a double bond between carbon atom, double line is used.
If stereoisomers are possible for the alkene, the stereoinformation is shown in the IUPAC name by adding prefix cis- or trans- with respect to the groups present on the same side of double bond or opposite side of double bond.
(c)

Answer to Problem 2.50EP
The IUPAC name for the given compound is trans-2-butene.
Explanation of Solution
Given compound is,
The longest continuous carbon chain present in the given compound is four carbon atoms. Hence, the parent alkane is butane.
As the given compound contains a double bond, the suffix –ane is replaced by –ene. Therefore, the name obtained is butene.
Numbering has to be given so that the double bond gets the least numbering. This gives the name as 2-butene.
Regarding the stereo informaton, the groups attached to the double‑bonded carbon atom has to be considered.
In this case, the methyl groups are present on opposite side of the double bond. Hence, trans- has to be included before the IUPAC name. The IUPAC name can be given as, trans-2-butene.
IUPAC name for the given molecule is assigned.
(d)
Interpretation:
The IUPAC name for the given molecule has to be assigned including the prefix cis- or trans-.
Concept Introduction:
IUPAC nomenclature for alkene: There are about eight rules to be followed in giving IUPAC name for alkene.
- The suffix –ane has to be replaced with the suffix –ene. This is used to indicate the presence of double bond.
- The longest continuous chain of carbon atoms has to be chosen that contains both carbon atoms of the double bond.
- The parent carbon chain has to be numbered in a way so that the numbering begins at the end near to the double bond. In case if the double bond is equidistant from both ends, then numbering has to be done from the end that is closer to substituents.
- The position of the double bond has to be given a single number which is lower‑numbered carbon atom that is present in the double bond.
- Suffixes like –diene, -triene, -tetrene, and so on are used when the compound contains more than one double bond.
- In case of cycloalkenes which do not have any substitution, the numbering is not needed to locate the double bond because the bond is assumed to be between the carbons 1 and 2.
- In case if substituents are present in cycloalkene, then the double‑bonded carbon atoms are numbered 1 and 2 in a direction where the substituent gets the lower number.
- If the cycloalkenes contain more than one double bond, then one double bond is assigned the numbers 1 and 2 followed by the other double bond so that the lowest number possible is given.
Structural formula where a line represent carbon‑carbon bond and the carbon atom is considered to be present in each point and the end of lines is known as Line-angle structural formula. To indicate a double bond between carbon atom, double line is used.
If stereoisomers are possible for the alkene, the stereoinformation is shown in the IUPAC name by adding prefix cis- or trans- with respect to the groups present on the same side of double bond or opposite side of double bond.
(d)

Answer to Problem 2.50EP
The IUPAC name for the given compound is 1,1-dibromoethene.
Explanation of Solution
Given compound is,
The longest continuous carbon chain present in the given compound is two carbon atoms. Hence, the parent alkane is ethane.
As the given compound contains a double bond, the suffix –ane is replaced by –ene. Therefore, the name obtained is ethene.
Numbering has to be given in a way that the carbon atoms present in the double bond gets the least numbering. Therefore, the name of the given compound is ethene. The substituent present on the longest carbon chain are bromine atoms that is present on the first carbon atom. Therefore, the name of the given molecule can be given as,
In order to include the stereo information, the groups attached to the double‑bonded carbon atoms are looked into.
The bulky groups are present on same carbon atom of the double bond. Hence, isomerism is not possible. Therefore, the IUPAC name of the given molecule is 1,1-dibromoethene.
IUPAC name for the given molecule is assigned.
Want to see more full solutions like this?
Chapter 2 Solutions
Organic And Biological Chemistry
- How many signals do you expect in the H NMR spectrum for this molecule? Br Br Write the answer below. Also, in each of the drawing areas below is a copy of the molecule, with Hs shown. In each copy, one of the H atoms is colored red. Highlight in red all other H atoms that would contribute to the same signal as the H already highlighted red. Note for advanced students: In this question, any multiplet is counted as one signal. Number of signals in the 'H NMR spectrum. For the molecule in the top drawing area, highlight in red any other H atoms that will contribute to the same signal as the H atom already highlighted red. If no other H atoms will contribute, check the box at right. No additional Hs to color in top molecule For the molecule in the bottom drawing area, highlight in red any other H atoms that will contribute to the same signal as the H atom already highlighted red. If no other H atoms will contribute, check the box at right. No additional Hs to color in bottom moleculearrow_forwardIn the drawing area below, draw the major products of this organic reaction: 1. NaOH ? 2. CH3Br If there are no major products, because nothing much will happen to the reactant under these reaction conditions, check the box under the drawing area instead. No reaction. Click and drag to start drawing a structure. ☐ : A คarrow_forwardPredict the major products of the following organic reaction: NC Δ ? Some important Notes: • Draw the major product, or products, of the reaction in the drawing area below. • If there aren't any products, because no reaction will take place, check the box below the drawing area instead. • Be sure to draw bonds carefully to show important geometric relationships between substituents. Note: if your answer contains a complicated ring structure, you must use one of the molecular fragment stamps (available in the menu at right) to enter the ring structure. You can add any substituents using the pencil tool in the usual way. Click and drag to start drawing a structure. Х аarrow_forward
- Predict the major products of this organic reaction. Be sure you use dash and wedge bonds to show stereochemistry where it's important. + ☑ OH 1. TsCl, py .... 文 P 2. t-BuO K Click and drag to start drawing a structure.arrow_forwardConsider this organic reaction: ( Draw the major products of the reaction in the drawing area below. If there won't be any major products, because this reaction won't happen at a significant rate, check the box under the drawing area instead. Click and drag to start drawing a structure. Х : а ค 1arrow_forwardIn the drawing area below, draw the major products of this organic reaction: If there are no major products, because nothing much will happen to the reactant under these reaction conditions, check the box under the drawing area instead. 1. NaH 2. CH3Br ? Click and drag to start drawing a structure. No reaction. : ☐ Narrow_forward
- + Predict the major product of the following reaction. : ☐ + ☑ ค OH H₂SO4 Click and drag to start drawing a structure.arrow_forwardConsider this organic reaction: ... OH CI Draw the major products of the reaction in the drawing area below. If there won't be any major products, because this reaction won't happen at a significant rate, check the box under the drawing area instead. ☐ No Reaction. Click and drag to start drawing a structure. : аarrow_forwardConsider the following reactants: Br Would elimination take place at a significant rate between these reactants? Note for advanced students: by significant, we mean that the rate of elimination would be greater than the rate of competing substitution reactions. yes O no If you said elimination would take place, draw the major products in the upper drawing area. If you said elimination would take place, also draw the complete mechanism for one of the major products in the lower drawing area. If there is more than one major product, you may draw the mechanism that leads to any of them. Major Products:arrow_forward
- Draw one product of an elimination reaction between the molecules below. Note: There may be several correct answers. You only need to draw one of them. You do not need to draw any of the side products of the reaction. OH + ! : ☐ + Х Click and drag to start drawing a structure.arrow_forwardFind one pertinent analytical procedure for each of following questions relating to food safety analysis. Question 1: The presence of lead, mercury and cadmium in canned tuna Question 2: Correct use of food labellingarrow_forwardFormulate TWO key questions that are are specifically in relation to food safety. In addition to this, convert these questions into a requirement for chemical analysis.arrow_forward
- Introductory Chemistry: An Active Learning Approa...ChemistryISBN:9781305079250Author:Mark S. Cracolice, Ed PetersPublisher:Cengage LearningChemistry: Matter and ChangeChemistryISBN:9780078746376Author:Dinah Zike, Laurel Dingrando, Nicholas Hainen, Cheryl WistromPublisher:Glencoe/McGraw-Hill School Pub Co

