Polymorphs, enantiomorphs, chirality and helicity in [Rh{N,O}(eta4-cod)] complexes with {N,O}=salicylaldiminato Schiff base or aminocarboxylato ligands.
Polymorphs, enantiomorphs, chirality and helicity in [Rh{N,O}(eta4-cod)] complexes with {N,O}=salicylaldiminato Schiff base or aminocarboxylato ligands.
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DOI：
10.1039/b820072f
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发表时间：
2009-05
影响因子：
4
通讯作者：
C. Janiak;Anne-Christine Chamayou;A. K. M. Royhan Uddin;M. Uddin;K. Hagen;M. Enamullah
中科院分区：
文献类型：
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作者：
C. Janiak;Anne-Christine Chamayou;A. K. M. Royhan Uddin;M. Uddin;K. Hagen;M. Enamullah
二聚配合物乙酰基(eta4-环辛基-1,5-二烯)铑(I)，[Rh(O2CMe)(eta4-cod)]2（cod = 环辛基-1,5-二烯）与N,O-螯合希夫碱配体或与N-苯基甘氨酸反应，得到二胺基-或 氨基羧基(4-环辛基-1,5-二烯)铑(I)络合物 [{Rh(eta4-cod)}2(salen)] (1)、[{Rh(eta4-cod)}2(salophen)] (2)、[Rh((S)-N-苯基甘氨酸)(eta4-cod)] (3S)、 [Rh(rac-N-苯基甘氨酸)(eta4-cod)] (3rac)、[Rh((R)-N-(4-甲氧基苯基)乙基-2-氧代-1-萘二胺)(eta4-cod)] (4) 和 [Rh(N-(邻甲苯基)-2-氧代-1-萘二胺)(eta4-cod)] (5) [salen2- = N,N-亚乙基-双(水杨醛亚胺), salophen2- = N,N-(1,2-亚苯基)-双(水杨醛亚胺)]。该配合物通过IR、UV/Vis、1H/13C-NMR 和质谱进行表征。配合物 1、2、4 和 5 含有接受 C-H...pi 接触的六元金属芳族 Rh-(N-CCC-O)-螯合环。 2 的晶体结构呈现出与先前报道的结构（2b，CSD 参考代码 SCLIRB10）不同的多晶型（二晶型）(2a)。多晶型2a和2b可追溯到相邻双核分子与其波纹范德华表面的不同联锁。非手性 N-苯基甘氨酸配体产生手性 N-苯基甘氨酸配合物 [Rh(O2C-CH2-NHPh)(eta4-cod)] (3)，其中氮原子在金属配位后成为立体中心。由于分子间 N-H...O 氢键仅将相同 (S-) 构型的分子连接成（右旋或 P-）41 螺旋链，配合物 3 可以在四方手性空间群 P41 中结晶为对映体 3S，外消旋混合物自发拆分为同手性螺旋对映体。结晶条件的变化得到3作为外消旋多晶型3rac。 R-和S-复合物3通过N-HO氢键沿着21轴平行链组装在多晶型物3rac中。同样，只有相同构型的分子才能组合成链，尽管相邻的链具有相反构型的复合物。手性对映体萘二胺配合物4呈现人字形排列。非手性化合物 5 在非中心对称极性空间群 Cc 中结晶，其中所有分子均显示相同的取向。
The dimeric complex acetato(eta4-cycloocta-1,5-diene)rhodium(I), [Rh(O2CMe)(eta4-cod)]2 (cod = cycloocta-1,5-diene) reacts with N,O-chelating Schiff-base ligands or with N-phenylglycine to afford the diminato- or aminocarboxylato(4-cycloocta-1,5-diene)rhodium(I) complexes [{Rh(eta4-cod)}2(salen)] (1), [{Rh(eta4-cod)}2(salophen)] (2), [Rh((S)-N-phenylglycinato)(eta4-cod)] (3S), [Rh(rac-N-phenylglycinato)(eta4-cod)] (3rac), [Rh((R)-N-(4-methoxphenyl)ethyl-2-oxo-1-naphthaldiminato)(eta4-cod)] (4) and [Rh(N-(o-tolyl)-2-oxo-1-naphthaldiminato)(eta4-cod)] (5) [salen2- = N,N-ethylene-bis(salicylaldiminato), salophen2- = N,N-(1,2-phenylene)-bis(salicylaldiminato)]. The complexes are characterized by IR-, UV/Vis-, 1H/13C-NMR- and mass-spectroscopy. Complexes 1, 2, 4 and 5 contain six-membered metallaaromatic Rh-(N-CCC-O)-chelate rings which accept C-H...pi contacts. The crystal structure of 2 presents a polymorph (dimorph) (2a) to a previously reported structure (2b, CSD refcode SCLIRB10). Polymorphic forms 2a and 2b are traced to a different interlocking of adjacent dinuclear molecules with their corrugated van der Waals surface. The achiral N-phenylglycine ligand gives a chiral N-phenylglycinato complex [Rh(O2C-CH2-NHPh)(eta4-cod)] (3) with the nitrogen atom becoming the stereogenic center upon metal coordination. Complex 3 can crystallize as the enantiomorph 3S in the tetragonal, chiral space group P41 in a spontaneous resolution of the racemic mixture into homo-chiral helix-enantiomers due to inter-molecular N-H...O hydrogen bonding which connects only molecules of the same (S-) configuration into (right-handed or P-) 41-helical chains. Variation of the crystallization conditions gives 3 as a racemic polymorphic 3rac. R- and S-complexes 3 assemble in the polymorph 3rac in parallel chains along the 21-axes through N-HO hydrogen bonding. Again, only molecules of the same configuration are combined into a chain, albeit neighboring chains have complexes of opposite configuration. The chiral enantiomeric naphthaldiminato complex 4 displays a herring-bone arrangement. Achiral compound 5 crystallizes in the non-centrosymmetric polar space group Cc where all molecules show the same orientation.