Q2(a)(ii). 7-Norbornyl and anti-7-norbornenyl tosylates: participation of a C=C
Show the products of the following reactions:
Answer in brief
(I) gives 7-norbornyl acetate , very slowly. (II) gives anti-7-norbornenyl acetate (retention) , 10¹¹ times faster, through the π-bridged non-classical cation. As printed (syn-TsO): no π participation; the product is exo-bicyclo[3.2.0]hept-3-en-2-yl acetate (rearranged).
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Coversneighbouring-group participationplanar cationanchimeric assistancenon-classicalanti-7-acetoxynorbornene
All parts of Question 2
- 2(a)(i) (S)-2-Bromobutane with HCOOH and with HCOO⁻Na⁺/DMSO5 marks
- 2(a)(ii) 7-Norbornyl and anti-7-norbornenyl tosylates: participation of a C=C5 marks
- 2(b) E2 in a locked trans-decalin and in locked 1,2-dibromocyclohexanes10 marks
- 2(c)(i) Bromolactonisation of endo-norbornene-carboxylic acid5 marks
- 2(c)(ii) Octalin to the tertiary and the secondary decalol5 marks
- 2(d) Aromatic character of sydnones10 marks