Concise Total Synthesis of (+)-Disparlure and its trans-Isomer Using Asymmetric Organocatalysis

Abstract

The efficient enantioselective synthesis of (+)-disparlure and its trans-isomer is described. This approach involves tandem asymmetric organocatalytic α-aminoxylation-allylation of an aldehyde and olefin cross metathesis using Grubbs’ catalyst as key steps.

Key words

disparlure - total synthesis - organocatalysis - asymmetric synthesis - olefin cross metathesis

References

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11

The ratio of E/Z-regioisomers in 10 (1:5), which was estimated by ^¹³C NMR spectroscopy, was not important because the double bond was reduced by hydrogenation in the next step.

13

We have found that Grubbs’ catalyst cleanly cleaved the N-O bond of 4 to furnish diol in the case of the absence of a cross-metathesis partner; detailed results will be published in due course.