Given that 1-phenyl-2-butene has an ultraviolet absorption at λ max = 208nm (∈ = 8000). On treatment with a small amount of strong acid it isomerizes to give a new compound with λ max = 250nm (∈ = 15,800). A structure for the isomer is to be proposed and a mechanism for its formation has to be suggested. Concept introduction: Among two isomers with same molecular formula, the isomer that has extended conjugation will have a higher λ max value than the other. To propose: A structure for the isomer which has an ultraviolet absorption at λ max = 250 nm (∈ = 15,800) obtained when 1-phenyl-2-butene with λ max = 208 nm (∈ = 8000) is treated with strong acids. Further to propose a mechanism for its formation.
Given that 1-phenyl-2-butene has an ultraviolet absorption at λ max = 208nm (∈ = 8000). On treatment with a small amount of strong acid it isomerizes to give a new compound with λ max = 250nm (∈ = 15,800). A structure for the isomer is to be proposed and a mechanism for its formation has to be suggested. Concept introduction: Among two isomers with same molecular formula, the isomer that has extended conjugation will have a higher λ max value than the other. To propose: A structure for the isomer which has an ultraviolet absorption at λ max = 250 nm (∈ = 15,800) obtained when 1-phenyl-2-butene with λ max = 208 nm (∈ = 8000) is treated with strong acids. Further to propose a mechanism for its formation.
Given that 1-phenyl-2-butene has an ultraviolet absorption at λmax = 208nm (∈ = 8000). On treatment with a small amount of strong acid it isomerizes to give a new compound with λmax = 250nm (∈ = 15,800). A structure for the isomer is to be proposed and a mechanism for its formation has to be suggested.
Concept introduction:
Among two isomers with same molecular formula, the isomer that has extended conjugation will have a higher λmax value than the other.
To propose:
A structure for the isomer which has an ultraviolet absorption at λmax = 250 nm (∈ = 15,800) obtained when 1-phenyl-2-butene with λmax = 208 nm (∈ = 8000) is treated with strong acids. Further to propose a mechanism for its formation.
How many chiral carbons are in the molecule?
OH
F
CI
Br
A mixture of three compounds Phen-A, Acet-B and Rin-C was analyzed using TLC
with 1:9 ethanol: hexane as the mobile phase. The TLC plate showed three spots
of R, 0.1 and 0.2 and 0.3.
Which of the three compounds (Phen-A; Acet-B or Rin-C) would have the highest
(Blank 1), middle (Blank 2) and lowest (Blank 3) spot respectively?
0
CH:
0
CH,
0
H.C
OH
H.CN
OH
Acet-B
Rin-C
phen-A
A
A
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