Q37E - Organic Chemistry (Mcmurry)

Question

Question: Give IUPAC names for the following compounds:

Step-by-Step Solution

Answer

a. 2-methyl 1,4-butanediol

b. 3-ethyl,2-hexanol

c. cis1,3 cyclobutanediol

d. cis-2methyl,4-cyclohepten-1-ol

e. cis 3-phenylcyclopentanol

f. 3-bromo 4-hydroxybenzonitrile

Step1: IUPAC nomenclature

It is method to give scientific name to the organic compounds recommended by the International Union of Pure and Applied Chemistry.

Step2: Nomenclature of alcohol

IUPAC rules used for naming of cycloalkanes

• Select the longest carbon chain
• the parent alkane chain and add suffix ol  
• Assign numbering to the substituents
• Assign the first number to the hydroxy group
• Halogens get the priority than others substituent 
• Write the name of the molecule in alphabetic

Step3: Naming of cycloalkane a, b, c

a.

1. The parent alkane is butane having 2 OH at 1 and 4 position group so butanediol.
2. Substituent is methyl 
3. Position of methyl is 2
4. So, the IUPAC name is 2-methyl 1,4-butanediol

compound A

b.

1. The parent alkane is hexane having OH at 2 position group so 2-hexaneol
2. Substituent is ethyl
3. Position of methyl is 3
4. So, the IUPAC name is 3-ethyl-2-hexanol  

compound B

c.

1. The parent cycloalkane is butane having 2 OH at 1 and 3 position group so cyclo butanediol
2. Position of the diol is cis so prefix cis is used
3. So, the IUPAC name is cis1,3 cyclo butanediol  

Compound C

Step 4: Naming of cycloalkane d, e, f

d.

1. The parent cycloalkene is cycloheptene having 1 OH at 1 so hepte-1-ol
2. Substituent is methyl 
3. Position of methyl is 2 and cis prefix is because diol is in cis position to each other.
4. So, the IUPAC name is cis-2methyl,4-cyclo hepten-1-ol

Compound D

e.

1. The parent cycloalkane is cyclo pentane having 1 OH at 1 so cyclopentanenol
2. Substituent is phenyl
3. Position of phenyl is 3 and cis prefix is because diol is in cis position to each other.
4. So, the IUPAC name is cis-2 phenyl cyclopentanenol

                            

Compound E

f.

1. The parent benzene having CN so benzonitrile
2. Substituent is bromo and hydroxy
3. Position of bromo is at 3 and hydroxy at 4
4. So, the IUPAC name is 3-bromo 4-hydroxy benzonitrile