Formation of Double Cubanes [Sn 7 (NR) 8 ] in the Reactions of Pyridyl and Pyrimidinyl Amines with Sn(NMe 2 ) 2 : A Synthetic and Theoretical Study
2002; American Chemical Society; Volume: 41; Issue: 6 Linguagem: Inglês
10.1021/ic011090r
ISSN1520-510X
AutoresDavid R. Armstrong, Francesca Benevelli, Andrew D. Bond, N. Feeder, E.A. Harron, Alexander D. Hopkins, Mary McPartlin, David Moncrieff, David Adrian Saez, Elsje Alessandra Quadrelli, Anthony D. Woods, Dominic S. Wright,
Tópico(s)Organometallic Compounds Synthesis and Characterization
ResumoIn contrast to the reactions of Sn(NMe2)2 with unfunctionalized primary amines (RNH2), which yield the simple imido SnII cubanes [SnNR]4, the reactions of 2-pyridyl or 2-pyrimidinyl amines give the mixed-oxidation-state SnII/SnIV double cubanes [Sn7(NR)8]. In addition to [Sn7{2-N(5-Mepy)}8]·2thf (1·2thf) (py = pyridine) and [Sn7{2-N(pm)}8]·0.33thf (2·0.33thf) (pm = pyrimidine), which were communicated previously, the syntheses and structures of the new complexes [Sn7{2-N(4-Mepm)}8]·2thf (3·2thf), [Sn7{2-N(4,6-Me2pm)}8]·4thf (4·4thf), [Sn7{2-N(4-Me-6-MeO-pm)}8] (5), and [Sn7{2-N(4-MeO-6-MeO-pm)}8] (6) are reported. Model DFT calculations on the reactions of Sn(NMe2)2 with 2-pmNH2 or PhNH2, producing the cubanes [Sn{2-N(pm)}]4 and [SnNPh]4 (respectively), and the corresponding double cubanes [Sn7{2-N(pm)}8] and [Sn7(NPh)8], show that the presence of intramolecular Sn···N bonding which spans the cubane halves of the complexes is crucial to the formation of the double-cubane structure.
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