Fundamentals of Organic ChemistryChemistryGeneral Organic Chemistry
Arrange the following alkenes in increasing order of their stability: (I) (II) (III) (IV)
Options
- A(IV) < (II) = (III) < (I)
- B(IV) < (II) < (III) < (I)
- C(IV) < (III) < (II) < (I)
- D(I) < (III) < (II) < (IV)
Correct answer
B. (IV) < (II) < (III) < (I)
Step-by-step solution
The stability of an alkene is directly proportional to the number of -hydrogens it possesses, as more -hydrogens lead to more hyperconjugative structures. Let us analyze the given alkenes: (I) The structure is 2,3-dimethylbut-2-ene. It is a tetrasubstituted alkene. The double-bonded carbons are attached to four methyl groups. Number of -hydrogens = 3 + 3 + 3 + 3 = 12 (II) The structure is hex-2-ene. It is a disubstituted alkene. The double-bonded carbons are attached to one methyl group and one propyl group. Number