Amaryllidaceae alkaloids are an important class of natural products especially as many members of the series display a wide range of potent biological activity. These properties include anticholinergic, antitumor, immunosuppresive, and analgesic activity, and they have also been shown to inhibit various cell cycle mechanisms (including HIV-1 activity), and have found recent application in the therapeutic treatment of Alzheimer×s disease.[1] Thus extensive synthetic studies of this family have been carried out over a number of years.[2, 3] Furthermore, the search for new members of the series has proved to be extremely profitable.[3, 4] The recently isolated compound ( )-plicamine (1) is especially attractive as it exemplifies many of the structural features of these natural Sellmann, E. Bˆhlen, M. Waeber, G. Huttner, L. Zsolnai, Angew. Chem. 1985, 97, 984; Angew. Chem. Int. Ed. Engl. 1985, 24, 981; f) D. Sellmann, W. Soglowek, F. Knoch, M. Moll, Angew. Chem. 1989, 101, 1244; Angew. 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Structural determination: direct methods[11] and fullmatrix least-squares refinement on all F2.[12] Anisotropic displacement parameters refined in both cases for all non-hydrogen atoms; hydrogen atoms were introduced in idealized positions. Phosphite and phenyl groups were restrained to agree with typical bonding geometry from the literature. Crystal data for 2-BPh4: C50H84BN2O13P4Re, MW 1242.12, crystal dimensions 0.3 0.2 0.2 mm3, space group P21/c, monoclinic, a 13.002(2), b 24.570(5), c 20.054(4) ä, 95.49(2) , V 6377(2) ä3, Z 4, calcd 1.308 gcm 3, max 30 , 18990 measured reflections (18537 unique), 4388 unique observed (I 2 (I)), R1 0.095, wR2 0.26 (on observed data), 176 restraints, 601 parameters, GOF 0.845. Crystal data for 3-BPh4: C50H83BNO13P4Re, MW 1227.11, crystal dimensions 0.4 0.3 0.2 mm3, space group P1≈, triclinic, a 15.393(5), b 16.977(5), c 12.916(5) ä, 100.02(5), 91.63(5), 71.08(5) , V 3143(2) ä3, Z 2, calcd 1.290 gcm 3, max 28 , 15138 measured unique reflections, 8634 unique observed (I 2 (I)), R1 0.048, wR2 0.115 (on observed data), 611 parameters, 79 restraints, GOF 0.912. CCDC-181120 (2-BPh4) and CCDC-181121 (3-BPh4) contain the supplementary crystallographic data for this paper. These data can be obtained free of charge via www.ccdc.cam.ac.uk/conts/ retrieving.html (or from the Cambridge Crystallographic Data Centre, 12, Union Road, Cambridge CB21EZ, UK; fax: ( 44)1223-336-033; or deposit@ccdc.cam.ac.uk). [10] A. C. T. North, D. C. Phillips, F. S. Mathews, Acta. Crystallogr. Sect. A 1968, 24, 351. [11] SIR97: A. Altomare, G. Cascarano, C. Giacovazzo, A. Guagliardi, M. C. Burla, G. Polidori, M. Camalli, J. Appl. Crystallogr. 1994, 27;, 435. [12] G. M. Sheldrick, SHELXL-97, Program for structure refinement, University of Gˆttingen, Gˆttingen (Germany), 1997. [13] W. A. Herrmann, L. K. Bell, M. L. Ziegler, H. Pfisterer, C. Pahl, J. Organomet. Chem. 1983, 247, 39. [14] J. Vicente, M. T. Chicote, M. D. Abrisqueta, R. Guerrero, P. G. Jones, Angew. Chem. 1997, 109, 1252; Angew. Chem. Int. Ed. Engl. 1997, 36, 1203. [15] D. A. Knight, M. A. Dewey, G. A. Stark, B. K. Bennett, A. M. Arif, J. A. Gladysz, Organometallics 1993, 12, 4523. [16] Coordination geometry for 2 : Re N 2.12(1), Re CO 2.14(1), Re P 2.354(4), NH N 1.251(4), N C 1.36(2), C O 1.12(1) ä; Re-N-N 145(2), N-N-C 123(2) . [17] Preliminary investigations show the presence of traces of ammonia in the final reaction mixture, but no other nitrogen-containing compound was unambiguously identified, and therefore no reaction path may be reasonably proposed. [18] Metal-mediated N N or N N bond activation is a topic of current interest. For some recent examples see: A. K. Verma, S. C. Lee, J. Am. Chem. Soc. 1999, 121, 10838; R. G. Peters, B. P. Warner, C. J. Burns, J. Am. Chem. Soc. 1999, 121, 5585; M. A. Aubart, R. G. Bergman, Organometallics 1999, 18, 811; F. Maseras, M. A. Lockwood, O. Eisenstein, I. P. Rothwell, J. Am. Chem. Soc. 1998, 120, 6598. [19] Interest in cleavage of the N N bond of hydrazine stems from its importance to inorganic and bioinorganic reducing system(s): a) A. E. Shilov, Metal Complexes in Biomimetic Chemical Reactions, CRC, Boca Raton, FL, 1997; b) R. R. Eady, Chem. Rev. 1996, 96, 3013; c) G. J. Leigh, Science 1995, 268, 827; d) R. R. Schrock, T. E. Glassman, M. G. Vale, J. Am. Chem. Soc. 1991, 113, 725; e) S. M. Malinak, K. D. Demadis, D. Coucouvanis, J. Am. Chem. Soc. 1995, 117, 3126; f) D. Sellmann, J. Sutter, Acc. Chem. Res. 1997, 30, 460.