Diastereoselective Synthesis of Arene Ruthenium(II) Complexes Containing Chiral Phosphetane-Based Tethers
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- 作者：Patrí ; cia Pinto ; Andreas W. Gö ; tz ; Guido Marconi ; Bernd A. Hess ; Angela Marinetti ; Frank W. Heinemann ; and Ulrich Zenneck
- 刊名：Organometallics
- 出版年：2006
- 出版时间：May 8, 2006
- 年：2006
- 卷：25
- 期：10
- 页码：2607 - 2616
- 全文大小：343K
- 年卷期：v.25,no.10(May 8, 2006)
- ISSN：1520-6041
文摘
Enantiomerically pure cyclic (R,R)-sulfates have been transformed into novel enantiopure ligands ofthe general type (S,S)-2,4-R2-1-(3-phenylpropyl)phosphetane (7a-c; R = Cy, i-Pr, t-Bu). 7a-c split thearene ruthenium complex dimer [{RuCl2(
6-C6H5COOMe)}2] (8) by forming the mononuclear 
complexes(SC,SC)-[RuCl2(6-C6H5COOMe){2,4-R2-1-(3-phenylpropyl)-1-phosphetane}] (9a-c). An intramoleculararene ligand displacement reaction leads to (SC,SC)-[RuCl2{2,4-R2-1-(6-3-phenylpropyl)-1-phosphetane}](10a-c) with tethered side chains of the arene ligand. Nucleophilic substitution of a chloride ligand byaniline with the assistance of NaPF6 gives access to the diastereomeric complex salts (SC,SC)-[RuCl(aniline){2,4-R2-1-(6-3-phenylpropyl)-1-phosphetane}] (11a-c). Good diastereoselectivities wereobtained with de values between 84 and 88%. The absolute structures of the major diastereomers of11a-c have been determined by X-ray structure analysis. RRu,SC,SC configurations were found in allcases. DFT calculations performed on the dechlorinated 16-valence-electron intermediate cation (SC,SC)-[RuCl{2,4-di-tert-butyl-1-(6-3-phenylpropyl)-1-phosphetane}]+ ([12]+) are in favor of an attack of anilinefrom the pro-RRu side of the complex. Investigation of the relative stabilities of the RRu and SRudiastereomers of the complex cation [11c]+ revealed an almost isoenergetic situation. The diastereoselectivity of the ligand exchange reaction is therefore believed to be kinetically controlled.
6-C6H5COOMe)}2] (8) by forming the mononuclear complexes(SC,SC)-[RuCl2(6-C6H5COOMe){2,4-R2-1-(3-phenylpropyl)-1-phosphetane}] (9a-c). An intramoleculararene ligand displacement reaction leads to (SC,SC)-[RuCl2{2,4-R2-1-(6-3-phenylpropyl)-1-phosphetane}](10a-c) with tethered side chains of the arene ligand. Nucleophilic substitution of a chloride ligand byaniline with the assistance of NaPF6 gives access to the diastereomeric complex salts (SC,SC)-[RuCl(aniline){2,4-R2-1-(6-3-phenylpropyl)-1-phosphetane}] (11a-c). Good diastereoselectivities wereobtained with de values between 84 and 88%. The absolute structures of the major diastereomers of11a-c have been determined by X-ray structure analysis. RRu,SC,SC configurations were found in allcases. DFT calculations performed on the dechlorinated 16-valence-electron intermediate cation (SC,SC)-[RuCl{2,4-di-tert-butyl-1-(6-3-phenylpropyl)-1-phosphetane}]+ ([12]+) are in favor of an attack of anilinefrom the pro-RRu side of the complex. Investigation of the relative stabilities of the RRu and SRudiastereomers of the complex cation [11c]+ revealed an almost isoenergetic situation. The diastereoselectivity of the ligand exchange reaction is therefore believed to be kinetically controlled.