Orgoreview

Give the structures of compounds B-D from the following data. 

(a) Compound B has a molecular formula of C₅H₆O, has 5 absorptions in the ¹³C NMR spectrum and is achiral. Compound B can be reduced with NaBH₄ in methanol to compound C.

(b) Compound C has a molecular formula of C₅H₈O, has 5 absorptions in the ¹³C NMR spectrum and is a racemic mixture. Compound C can be reduced with H₂/Pd-C to give compound D.

(c) Compound D has a molecular formula of C₅H₁₀O, has only 3 absorptions in the ¹³C NMR spectrum and is achiral.