Synthesis of a-Atlantone from -Limonene

Friedel-Crafts reaction between senecioyl chloride (6.96) and d-limonene (6.102) in the presence of stannic chloride at low temperature, gave a-atlantone in one step, along with the isomeric ketones 

2 Tagetones, Filifolone and Minor Components of Atlas Cedarwood 

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