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UPSC Civil Services (Mains)

Chemistry optional

  • 2 papers
  • 250 marks each
  • 3 h per paper
  • 5 of 8 questions, Q1 and Q5 compulsory

Paper I covers physical and inorganic chemistry.

UPSC Civil Services (Mains), Chemistry optional · 2023 · Paper I

Q8(a). Acetylferrocene and ferrocenecarboxylic acid from ferrocene

Question

Sketch the synthesis of [Fe(η⁵-C₅H₅)(η⁵-C₅H₄COCH₃)] and [Fe(η⁵-C₅H₅)(η⁵-C₅H₄COOH)] starting from [Fe(η⁵-C₅H₅)₂].

Answer in brief

Ferrocene + CH₃COCl/AlCl₃ gives acetylferrocene (Friedel–Crafts acylation); ferrocene + t-BuLi gives lithioferrocene, then CO₂ and H₃O⁺ give ferrocenecarboxylic acid.

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CoversferroceneacetylferroceneFriedel–Crafts acylationlithiationferrocenecarboxylic acidorganometallic synthesis

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