Chiral Quaternary Carbon Compounds. Ii. an Asymmetric Synthesis of (r) or (s)-4,4-dialkyl-z-cyclopentenones
نویسنده
چکیده
The chiral bicyclic lactam (2) derived from levulinic acid and (S)-valinol is sequentially alkylated and then cleaved to 2,2-dialkyl levulinaldehyde (5) which is cyclized to the title products (2) in > 99% ee.
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