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252 Organic Chemistry Solutions Manual Suggested solution The three diketones have 1,3-, 1,4-, and 1,5-dicarbonyl relationships. In each case the disconnection is the bond joining the ring to the chain. For the 1,3-diketone, this means acylation a ketone. analysis 0 0 0 0 1,3-dico specific enol(ate) equivalent needeo R + R synthesis 0 0 Me₃SiCI RCOCI R Et3N The same disconnection on the 1,4-diketone leads to totally different chemistry and require different specific enol(ate) equivalent for cyclopentanone. analysis 0 0 R R nonbasic + Br specific enol(ate) equivalent needed 0 0 synthesis 0 NR₂ R₂NH R R + Br 0 0 The 1,5-diketone requires a conjugate addition approach and we use a different specific equivalent more for variety than necessity. analysis 0 0 0 specific enol(ate) R + R equivalent needed synthesis 0 0 0 1. CO₂Et 1. NaOH TM CO₂Et 2. 0 R 2. heat R Problem 9 Suggest syntheses for these compounds. (Hint. Look out for a 1,4-dicarbonyl 0 CO₂Et Purpose of the problem Further exploration of the 1,4-diCO relationship but disguised by further chemistry.