Q3(c)(ii). Photolysis of the α-diazoketone in methanol
Write the structure of the product formed and the steps involved in the following reaction: photolysis (hν) of a bicyclic α-diazoketone in MeOH. [structure of the bicyclo[2.2.2]octanone-derived α-diazoketone given in the paper]
Answer in brief
Product: methyl bicyclo[2.2.1]heptane-7-carboxylate, by a photochemical Wolff rearrangement (ring contraction).
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CoversWolff rearrangementα-diazoketoneketenering contractionArndt–Eistert
All parts of Question 3
- 3(a)(i) Products of two reactions10 marks
- 3(a)(ii) Ketone A from isobutanol alone5 marks
- 3(b)(i) Cyclopropane from tert-butyl chloroacetate and ethyl acrylate10 marks
- 3(b)(ii) Structures of C and D5 marks
- 3(c)(i) Missing reagents and intermediate10 marks
- 3(c)(ii) Photolysis of the α-diazoketone in methanol10 marks