Concept explainers
a) -CH3, -Br, -H, -I.
Interpretation:
To rank -CH3, -Br, -H, -I according to Cahn-Ingold-Prelog sequence rules.
Concept introduction:
According to Cahn-Ingold-Prelog sequence rules the member that ranks higher can be determined by considering the
To rank:
The substituents, -CH3, -Br, -H, -I, according to Cahn-Ingold-Prelog sequence rules.
Answer to Problem 45AP
According to Cahn-Ingold-Prelog sequence rules the substituents can be ranked in the order -I, -Br, -CH3, -H.
Explanation of Solution
The first atoms in the substituents given are I, Br, C and CH. Their atomic numbers are 53, 35, 12, 1 respectively. Based on these atomic numbers, the substituents can be ranked in the order -I, -Br, -CH3, -H.
According to the sequence rules the substituents can be ranked in the order -I, -Br, -CH3, -H.
b) -OH, -OCH3, -H, -CO2H.
Interpretation:
To rank -OH, -OCH3, -H, -CO2H according to Cahn-Ingold-Prelog sequence rules.
Concept introduction:
According to Cahn-Ingold-Prelog sequence rules the member that ranks higher can be determined by considering the atomic number of the first atom in each substituent. The atom with highest atomic number gets a higher rank. If a decision cannot be made by considering the atomic number of the first atom in each substituent then the second, third, fourth atoms can be considered until the first difference is found. Multiple bonded atoms are equivalent to the same number of single bonded atoms.
To rank:
The substituents, -OH, -OCH3, -H, -CO2H according to Cahn-Ingold-Prelog sequence rules.
Answer to Problem 45AP
According to Cahn-Ingold-Prelog sequence rules the substituents can be ranked in the order -OCH3, -OH, -CO2H, -H.
Explanation of Solution
Two groups have oxygen as first atom, third one has carbon as the first atom and the fourth one is H. Their atomic numbers are 8, 1, 12 respectively. Both -OH, -OCH3 have O as the first atom. Hence the second, third and fourth atoms to which they are bonded are to be considered. Oxygen in -OH is bonded to H, while the oxygen in -OCH3 is bonded to carbon. Hence -OCH3 ranks higher than -OH. The substituent -CO2H ranks third and -H the fourth.
According to the sequence rules the substituents can be ranked in the order -OCH3, -OH, -CO2H,-H.
c) -CO2H, -CO2CH3, -CH2OH, -CH3.
Interpretation:
To rank -CO2H, -CO2CH3, -CH2OH, -CH3 according to Cahn-Ingold-Prelog sequence rules.
Concept introduction:
The member that ranks higher can be determined by considering the atomic number of the first atom in each substituent. The atom with highest atomic number gets a higher rank. If a decision cannot be made by considering the atomic number of the first atom in each substituent then the second, third, fourth atoms can be considered until the first difference is found. Multiple bonded atoms are equivalent to the same number of single bonded atoms.
To rank:
The substituents -CO2H, -CO2CH3, -CH2OH, -CH3 according to Cahn-Ingold-Prelog sequence rules.
Answer to Problem 45AP
According to Cahn-Ingold-Prelog sequence rules the substituents can be ranked in the order -CO2CH3, -CO2H, -CH2OH, -CH3.
Explanation of Solution
The first atom in all the substituents given is C. Hence the second, third and fourth atoms to which they are bonded are to be considered. Carbon in -CO2CH3 is bonded to three oxygens(double bond) out of which one is attached to a carbon. Carbon in COOH is also bonded to three oxygen atom (double bond) out of which one is attached to a hydrogen. Carbon in –CH2OH is bonded to H, H, O. Carbon in methyl is bonded to H, H, H. Based on the atomic numbers of the differentiating atoms, the substituents can be ranked in the order -CO2CH3, -CO2H, -CH2OH,-CH3.
According to Cahn-Ingold-Prelog sequence rules the substituents can be ranked in the order -CO2CH3, -CO2H, -CH2OH,-CH3.
d) -CH3, -CH2CH3, -CH2CH2OH, -COCH3.
Interpretation:
To rank -CH3, -CH2CH3, -CH2CH2OH, -COCH3 according to Cahn-Ingold-Prelog sequence rules.
Concept introduction:
The member that ranks higher can be determined by considering the atomic number of the first atom in each substituent. The atom with highest atomic number gets a higher rank. If a decision cannot be made by considering the atomic number of the first atom in each substituent then the second, third, fourth atoms can be considered until the first difference is found. Multiple bonded atoms are equivalent to the same number of single bonded atoms.
To rank:
The substituents -CH3, -CH2CH3, -CH2CH2OH, -COCH3 according to Cahn-Ingold-Prelog sequence rules.
Answer to Problem 45AP
According to Cahn-Ingold-Prelog sequence rules the substituents can be ranked in the order -COCH3, -CH2CH2OH, -CH2CH3, -CH3.
Explanation of Solution
The first atom in all the substituents given is C. Hence the second, third and fourth atoms to which they are bonded are to be considered.
Carbon in -COCH3 is bonded to O, O(double bond), C.
Carbon in -CH2CH2OH is bonded to H, H & C attached to H, H, O.
Carbon in –CH2CH3 is bonded to H, H & C attached to three hydrogens.
Carbon in methyl is bonded to H, H, H.
Based on the atomic numbers of the differentiating atoms, the substituents can be ranked in the order -COCH3, -CH2CH2OH, -CH2CH3, -CH3.
According to Cahn-Ingold-Prelog sequence rules the substituents can be ranked in the order -COCH3, -CH2CH2OH, -CH2CH3, -CH3.
e) -CH=CH2, -CN, -CH2NH2, -CH2Br.
Interpretation:
To rank -CH=CH2, -CN, -CH2NH2, -CH2Br according to Cahn-Ingold-Prelog sequence rules.
Concept introduction:
The member that ranks higher can be determined by considering the atomic number of the first atom in each substituent. The atom with highest atomic number gets a higher rank. If a decision cannot be made by considering the atomic number of the first atom in each substituent then the second, third, fourth atoms can be considered until the first difference is found. Multiple bonded atoms are equivalent to the same number of single bonded atoms.
To rank:
The substituents -CH=CH2, -CN, -CH2NH2, -CH2Br according to Cahn-Ingold-Prelog sequence rules.
Answer to Problem 45AP
According to Cahn-Ingold-Prelog sequence rules the substituents can be ranked in the order -CH2Br, -CN, -CH2NH2, -CH=CH2.
Explanation of Solution
The first atom in all the substituents given is C. Hence the second, third and fourth atoms to which they are bonded are to be considered.
Carbon in -CH=CH2, is bonded to C, C(double bond), H.
Carbon in -CN, is bonded to three nitrogens.
Carbon in -CH2NH2 is bonded to N, H, H.
Carbon in -CH2Br is bonded to Br, H, H.
Based on the atomic numbers of the differentiating atoms, the substituents can be ranked in the order -CH2Br, -CN, -CH2NH2, -CH=CH2.
According to Cahn-Ingold-Prelog sequence rules the substituents can be ranked in the order -CH2Br, -CN, -CH2NH2, -CH=CH2.
f) -CH=CH2, -CH2CH3, -CH2OCH3, -CH2OH.
Interpretation:
To rank -CH=CH2, -CH2CH3, -CH2OCH3, -CH2OH according to Cahn-Ingold-Prelog sequence rules.
Concept introduction:
The member that ranks higher can be determined by considering the atomic number of the first atom in each substituent. The atom with highest atomic number gets a higher rank. If a decision cannot be made by considering the atomic number of the first atom in each substituent then the second, third, fourth atoms can be considered until the first difference is found. Multiple bonded atoms are equivalent to the same number of single bonded atoms.
To rank:
The substituents -CH=CH2, -CH2CH3, -CH2OCH3, -CH2OH according to Cahn-Ingold-Prelog sequence rules.
Answer to Problem 45AP
According to Cahn-Ingold-Prelog sequence rules the substituents can be ranked in the order -CH2OCH3, -CH2OH, -CH=CH2, CH2CH3.
Explanation of Solution
The first atom in all the substituents given is C. Hence the second, third and fourth atoms to which they are bonded are to be considered.
Carbon in -CH=CH2, is bonded to C, C(Double bond), H.
Carbon in -CH2CH3 is bonded to C, H, H.
Carbon in -CH2OCH3 is bonded to H, H, O attached to a carbon.
Carbon in -CH2OH is bonded to H, H, O attached to a hydrogen.
Based on the atomic numbers of the differentiating atoms, the substituents can be ranked in the order -CH2OCH3, -CH2OH, -CH=CH2, CH2CH3.
According to Cahn-Ingold-Prelog sequence rules the substituents can be ranked in the order -CH2OCH3, -CH2OH, -CH=CH2, CH2CH3.
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Chapter 7 Solutions
Organic Chemistry
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EBK A SMALL SCALE APPROACH TO ORGANIC LChemistryISBN:9781305446021Author:LampmanPublisher:CENGAGE LEARNING - CONSIGNMENT