Bisoxazolidine 1 is an effective ligand in the Me2Zn-promoted and the Cu(I)-catalyzed Henry reaction. While a wide range of nitroaldol products are obtained in high yields and ee's in both cases, the replacement of dimethylzinc with copper(I) acetate results in a complete reversal of the sense of asymmetric induction. The Cu(I)-catalyzed enantioselective addition of nitromethane to methyl 4-oxobutanoate followed by hydrogenation and spontaneous lactamization gives (S)-5-hydroxypiperidin-2-one in 72% overall yield and 98% ee which compares favorably with previously reported methods.
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DISTRIBUTION/AVAILABILITYSTATEMENT 13. SUPPLEMENTARY NOTES 14. ABSTRACT 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: 19a. NAME OF RESPONSIBLE PERSON a. REPORT b. ABSTRACT c. THIS PAGE 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19b. TELEPHONE NUMBER (Include area code) Standard Form 298 (Rev. 8/98)Rate-stick experiments were performed and digital high-speed framing-camera images were captured to determine energetic material detonation wave velocities. Rate-stick experiments consisting of 20-mm-diameter pressed pellets having a length-to-diameter (L/D) ratio of 1, with the total charge having a L/D of 10, were conducted. Digital high-speed images were recorded at rates upwards of 2.5 million frames/s using a Cordin model 570 rotating-mirror framing camera. Individual images were analyzed to determine the pixel position at which the reaction products break out from the energetic material-air interface. Position-time records were constructed and best-fit lines applied to the data to determine detonation velocities. The results of three different energetic materials are presented. Detonation velocities were found to be in good agreement with piezo-pin velocity measurements concurrently taken.Optical detonation velocity, Rate stick, Framing camera, High-speed UU 18
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