Azridine

Joseph P.A. Harrity of the University of Sheffield has reported (J. Org. Chem. 2005, 70, 207) a complementary approach to enantiomerically-pure piperidines. Alkylated azridines such as 17 are readily available from aspartic acid. Pd-catalyzed condensation of 17 with the Trost reagent 18 was found to be most effectively mediated by bis-phosphines such as dppp , 1,3-bis-diphenylphosphinopropane. The piperidine 19 was the key intermediate for the preparation of several of the Nuphar alkaloids, including 20. 

SYNS C 3172 ENT 50,003 MAPO METEPA METPiAPHOXIDE METHYL APHOXIDE 1,1, "-PHOSPHINYLIDYNETRIS(2-METHYL)AZRIDINE TRIS(2-METHYL-l-AZIRIDINYL)PHOSPHINE OXIDE TRIS(2-METHYLAZIRIDIN-l-YL)PHOSPHINE OXIDE NI, N"-TRIS(l-METHYLETHYLENE)PHOSPHORAMIDE... 

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