An alkene A, C6H12, gives only propanoic acid on heating with concentrated alkaline KMnO4 followed by acidification. With cold dilute alkaline KMnO4 it gives a meso diol. A is

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An alkene A, $C X_{6} H X_{12}$ , gives only propanoic acid on heating with concentrated alkaline $KMnO X_{4}$ followed by acidification. With cold dilute alkaline $KMnO X_{4}$ it gives a meso diol. A is

A(Z)-hex-3-ene
B(E)-hex-3-ene
C(E)-hex-2-ene
D2-ethylbut-1-ene

Answer: A

Propanoic acid as the only acid means the alkene is symmetrical,

CH X_{3} CH X_{2} CH = CHCH X_{2} CH X_{3}

, i.e. hex-3-ene. Syn dihydroxylation of the Z isomer gives the meso diol (3R,4S), while the E isomer gives the racemic (R,R)/(S,S) pair. So A is (Z)-hex-3-ene.

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An alkene A, CX6​HX12​, gives only propanoic acid on heating with concentrated alkaline KMnOX4​ followed by acidification. With cold dilute alkaline KMnOX4​ it gives a meso diol. A is

Answer: A

More questions on Oxidation with KMnO4, K2Cr2O7, PCC, Jones

An alkene A, $C X_{6} H X_{12}$ , gives only propanoic acid on heating with concentrated alkaline $KMnO X_{4}$ followed by acidification. With cold dilute alkaline $KMnO X_{4}$ it gives a meso diol. A is