Applying the macrocyclic effect to smaller ring structures. N,N'-dimethyl-3,7-diazabicyclo[3.3.1]nonane nickel(0) complexes

Journal of the American Chemical Society

Volumn 119, Issue 34, 1997, Pages 7992-7999

  Haack, Karl Josef ^a   Goddard, Richard ^a   Pörschke, Klaus Richard ^a  

^a MAX PLANCK INSTITUT FÜR KOHLENFORSCHUNG   (Germany)

Author keywords

[No Author keywords available]

Indexed keywords

NICKEL; ORGANOMETALLIC COMPOUND; TERTIARY AMINE;

ARTICLE; CHELATION; CHEMICAL STRUCTURE; COMPLEX FORMATION; CONFORMATION; NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY; SYNTHESIS;

EID: 0030818606     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja971037v     Document Type: Article

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95. Although illustrative, this fact alone does not explain the stability of the complexes because both (-)-sparteine and N,N′-dimethyl-3,7-diazabicyclo[3.3.1]nonan-9-one fail to form a nickel(0)-ethene complex. The stability of complexes 1-4 is based on the optimal geometry of free dabn, which is superior to that of the above-mentioned reference diamines with a bispidine skeleton (leaving α-isosparteine out of consideration). It is, however, conceivable that a different bicyclic or multicyclic structure would also give a satisfactory arrangement of the N atoms.
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102. (b) Jonas, K.; Krüger, C. Angew. Chem. 1980, 92, 513; Angew. Chem., Int. Ed. Engl. 1980, 19, 520. Jonas, K. Adv. Organomet. Chem. 1981, 19, 97 and literature cited therein.
103. For a detailed treatment of this matter, see: Pearson, R. G. Inorg. Chem. 1988, 27, 734.
104. (a) Examples of common and medium-sized rings in coordination chemisty: 1,5-cyclooctadiene (cod), 1,4,7-triazacyclononane, 1,5,9-cyclododecatriene isomers. Example of bicyclic rings: norbornadiene. Examples of multicyclic rings: sparteine, α-isosparteine.
105. 35 (58) Since the reaction used to prepare dabn only has a yield of ∼2%, we would welcome a more efficient synthesis of dabn.
106. Michaelis, S. Ph.D. Dissertation, Universität Bochum, 1991.