Question

Solving the following road-map problem depends on determining the structure of A, the key intermediate. Give structures for compounds A through K.

Short answer

The identity of A is hept-2-one.

Step-by-step solution

Determining the structure of A, the key intermediate

The identity of A is hept-2-one.

Structure of compounds from A through K

(a) hept-2-one reacts with phenylmagnesiumbromide and H₃O⁺ forms 2-hydroxy-2phenylheptane.

hept-2-one 2-hydroxy-2phenylheptane

(b) hept-2-one reacts with a Grignard reagent and H₃O⁺ to form another product as 3-(1-hydroxy-1'methylhexyl)cylcohexanone.

hept-2-one 3-(1-hydroxy-1'methylhexyl)cylcohexanone

(c) hept-2-one reacts with HCN to form 2-hydroxy-2-methylhetanenitirile which undergoes hydrolysis to give 2-hydroxy-2-methylhetanoicacid.

(d) pentylmagensiumbromide on treatment with ethanal and H₃O⁺ forms 2-hydroxyheptane which on further treatment with NaOCL/HOAc undergoes oxidation to give hept-2-one.

(e) hexanoic on treatment with SOCl₂ to form hexanoyl which further reacts with Gilman reagent to give hept-2-one.

(f) Hydration of hept-1-yne takes place in presence of catalyst HgSO₄ , H₂ SO₄ / H₂O to hept-2-one.

(g) 2-methyl-heptan-1-ene undergoes ozonolysis which converts the alkene into carbonyl compound ( hept-2-one).