Introducing Stereogenic Centers to Group XIV Metallatranes
Britta Glowacki1, Michael Lutter1, Hazem Alnasr1
1Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund , 44221 Dortmund, Germany.
Abstract:
The syntheses of the novel amino alcohols NH(CH2CMe2OH)2(CMe2CH2OH) (1) and N(CH2CMe2OH)(CMe2CH2OH)(CH2CH2OH) (2) as well as the stannatranes N(CH2CMe2O)(CMe2CH2O)(CH2CH2O)SnX (3, X = Ot-Bu), N(CH2CMe2O)3SnOC(O)C9H13O2, 4, and germatranes N(CH2CMe2O)(CMe2CH2O)(CH2CH2O)GeX (5, X = OEt; 6, X = Br) are reported. The compounds were characterized by 1H, 13C (1-6), 119Sn (3, 4), and 15N (2, 3, 5) NMR and IR spectroscopy, electrospray ionization mass spectrometry, and single crystal X-ray diffraction analysis. Graphset analyses were performed for compounds 1 and 2. Detailed NMR spectroscopic studies including variable temperature 1H (3, 5, 6) and 119Sn (3, 4) DOSY experiments reveal the stannatrane 3 being involved in a monomer-dimer equilibrium. Both the stannatranes 3 and 4 as well as the germatranes 5 and 6 show Λ ⇌ Δ isomerization of the atrane cages in solution.
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