Naphthalene is reduced with Na in liquid NH3 containing ethanol to give a dihydro compound C10H10. This is ozonised (O3, then Zn/H2O). The major organic product is

benzene-1,2-diacetaldehyde (C6H4(CH2CHO)2, ortho)

phthalaldehyde (benzene-1,2-dicarbaldehyde)

benzene-1,2-diacetaldehyde (C6H4(CH2CHO)2, ortho)

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Naphthalene is reduced with Na in liquid $NH X_{3}$ containing ethanol to give a dihydro compound $C X_{10} H X_{10}$ . This is ozonised ( $O X_{3}$ , then $Zn / H X_{2} O$ ). The major organic product is

Aphthalaldehyde (benzene-1,2-dicarbaldehyde)
Bbenzene-1,2-diacetaldehyde ( $C X_{6} H X_{4} (CH X_{2} CHO) X_{2}$ , ortho)
C3-(2-formylphenyl)propanal
Dphthalic acid

Answer: B

Naphthalene is reduced at C-1 and C-4 of one ring, giving 1,4-dihydronaphthalene while the other ring stays aromatic. The remaining isolated C2=C3 double bond is cleaved by ozone with reductive work-up into two CHO groups, each attached through a CH2 to the benzene ring. The product is ortho-

C X_{6} H X_{4} (CH X_{2} CHO) X_{2}

Practice Reduction, Oxidation and Hydrolysis in Organic Chemistry More on Dissolving metal reductions (Birch, Na/NH3)

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Naphthalene is reduced with Na in liquid NHX3​ containing ethanol to give a dihydro compound CX10​HX10​. This is ozonised (OX3​, then Zn/HX2​O). The major organic product is

Answer: B

More questions on Dissolving metal reductions (Birch, Na/NH3)

Naphthalene is reduced with Na in liquid $NH X_{3}$ containing ethanol to give a dihydro compound $C X_{10} H X_{10}$ . This is ozonised ( $O X_{3}$ , then $Zn / H X_{2} O$ ). The major organic product is