Answer
The IUPAC names of the compounds are:
(a) (E)-4-Methylhex-2-ene
(b) (Z)-4-Ethyl-3,7-dimethyloct-2-ene
(c) 2-Ethylbut-1-ene
(d) (5E)-3,4-Dimethylhepta-1,5-diene
(e) (2Z,4E)-4,5-Dimethylocta-2,4-diene
(f) Buta-1,2-diene
Work Step by Step
For
(a) (E)-4-Methylhex-2-ene
(b) (Z)-4-Ethyl-3,7-dimethyloct-2-ene
(d) (5E)-3,4-Dimethylhepta-1,5-diene
(e) (2Z,4E)-4,5-Dimethylocta-2,4-diene
The longest chain of carbon atoms is identified and numbered. Substituents are also provided locants/numbers. The groups on either side of the double bond are assigned priorities and if two groups having higher priority are on the same side of the double bond, they are assigned a Z configuration. If the higher priority groups are on opposite side of the double bond, they are assigned an E configuration.
If two double bonds are present, the suffix -diene is used and the E,Z configurations of both the double bonds are determined, wherever possible.
For
(c) 2-Ethylbut-1-ene
(f) Buta-1,2-diene
The longest chain of carbon atoms is counted and the position of double bonds and substituents is indicated.
