UPSC Combined Geo-Scientist, Mains · 2020 · Mains Paper III
Q8(c)(ii). UV maximum of a steroidal tetraene
Question
Calculate λₘₐₓ for B, the depicted acetoxy-substituted steroidal conjugated tetraene.
Answer in brief
λₘₐₓ≈353 nm using the homoannular-diene parent.
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CoversUV maximum of a steroidal tetraeneWoodward–Fieser calculation
All parts of Question 8
- 8(a) Robinson annulation10 marks
- 8(b) Benzilic acid rearrangement of phenanthrenequinone10 marks
- 8(c)(i) UV maximum of a bicyclic enone5 marks
- 8(c)(ii) UV maximum of a steroidal tetraene5 marks