5460
Figure 5. Synthesis of peroxyalkenals
In conclusion, reaction of silyl ketene acetals with peroxyacetals provides an ecient approach
to 3-peroxyalkanoates and 3-peroxyalkanals. Investigation of asymmetric versions of this trans-
formation and applications to the total synthesis of peroxide natural products are in progress.
Acknowledgements
We are grateful to the NIH for support and to Professor Richard Shoemaker for assistance
with NMR experiments.
References
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1
Rf=0.53 in 10% EA/hexane; H NMR 4.23 (m, 1H), 4.10 (m, 2H), 3.08 (qd, 1H, J=7.16, 5.60), 1.08 (d, 3H,
J=7.16), 1.40±0.80 (18H), 0.8 (s, 6H). Anal. calcd for C15H34O4Si: C, 60.33; H, 10.76. Found: C, 60.24; H, 10.74.
1
Ethylthio (4E)-3-(1,1-dimethylethyldimethylsilyldioxy)-4-undecenoate: Rf=0.6 (10% EtOAc/hexanes); H NMR
(300 MHz) 5.73 (dt, 1H, J=15.2, 6.7), 5.35 (ddt, 1H, J=15.5, 7.8, 1.4), 4.71 (q, 1H, J=6.7), 3.08 (dd, 1H, J=14.5,
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