Synthesis and characterization of 3- and 4-phenylgermatranes: X-ray crystal structures of N(CH2CH2O) 2(CH2CHPhO)GeZ (Z=F, OSiMe3, C≡CPh) and N(CH2CH2O)2 (CHPhCH2O)GeOH

Abstract Reaction of excess of product A [(HOCH2CH2)2NCH2CH(Ph)OH (1):(HOCH2CH2)2NCH(Ph)CH2OH (2)=9:1] with GeCl4 led to a mixture of 1-chloro-3-phenylgermatrane (3) and 1-chloro-4-phenylgermatrane (4). Compound 4 was isolated in yield 9% from this mixture. Reaction of (EtO)3GeCl with product A gave 3 in yield 55%. 1-(Phenylethynyl)-3-phenylgermatrane (5) was prepared in yield 31% by treatment of (EtO)3GeCCPh with product A. Reaction of product A with mixture of GeO2 and H2O produced N(CH2CH2O)2(CH2CHPhO)GeOH (6) in yield 73%. The presence of N(CH2CH2O)2(CHPhCH2O)GeOH (7) among the products of this reaction was confirmed by 1H-, 13C-NMR spectroscopy and X-ray analysis. N(CH2CH2O)2(CH2CHPhO)GeF (8) is formed by the treatment of 6 with BF3·Et2O. N(CH2CH2O)2(CH2CHPhO)GeOSiMe3 (9) was obtained by silylation of 6 with (Me3Si)2NH or Me3SiCl–Et3N. Refluxing of a suspension of 6 in xylene with continuous removal of water by azeotropic distillation afforded [N(CH2CH2O)2(CH2CHPhO)Ge]2O (10). 9 reacted with SOCl2, Me3SiBr and Me3SiOTf to give N(CH2CH2O)2(CH2CHPhO)GeX (3, X=Cl; 11, X=Br; 12, X=OTf), respectively. Reaction of 11 with Et3SnOMe led to the formation of N(CH2CH2O)2(CH2CHPhO)GeOMe (13). Germatranes N(CH2CH2O)2(CH2CHPhO)GeY [14, Y=Flu (fluorenyl); 15, Y=N(SiMe3)2] were obtained from the nucleophilic substitution of the substituent X in N(CH2CH2O)2(CH2CHPhO)GeX (X=OSiMe3, Br) with the corresponding LiY. All compounds were characterized by 1H- and 13C-NMR spectroscopy and mass spectrometry. Single-crystal structures of 5 and 7–9 were determined by X-ray diffraction studies.