Chiral-at-Metal Compounds [CpFe(Prophos)L] (L = Cl, I, CN), [CpFe(Prophos)CO]X (X = I, PF6), and [IndFe(Prophos)CO]I

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• 作者：Henri Brunner ; Hayato Ike ; Manfred Muschiol ; Takashi Tsuno ; Naohisa Umegaki ; Manfred Zabel
• 刊名：Organometallics
• 出版年：2011
• 出版时间：February 14, 2011
• 年：2011
• 卷：30
• 期：3
• 页码：414-421
• 全文大小：931K
• 年卷期：v.30,no.3(February 14, 2011)
• ISSN：1520-6041

文摘

The compounds [CpFe(Prophos)Cl] and [CpFe(Prophos)I] were prepared in photochemical reactions of [CpFe(CO)₂Cl] and [CpFe(CO)₂I] with (R)-Prophos. They consist of pairs of R_Fe,R_C and S_Fe,R_C diastereomers which only differ in the configuration at the metal atom. The diastereomerically pure compounds (S_Fe,R_C)-[CpFe(Prophos)Cl] and (R_Fe,R_C)-[CpFe(Prophos)I], which have the same relative configurations, were isolated. They epimerize via change of the Fe configuration and approach the equilibria (R_Fe,R_C)-/(S_Fe,R_C)-[CpFe(Prophos)Cl] = 5/95 and (R_Fe,R_C)-/(S_Fe,R_C)-[CpFe(Prophos)I] = 95/5 in first-order reactions with half-lives of 43 min at 20 掳C and 50 min at 50 掳C in C₆D₆, respectively. The reaction of (R_Fe,R_C)-/(S_Fe,R_C)-[CpFe(Prophos)I] = 95/5 with KCN afforded the cyano complex [CpFe(Prophos)CN] in the diastereomer ratio R_Fe,R_C/S_Fe,R_C = 50/50. Both diastereomers (R_Fe,R_C)- and (S_Fe,R_C)-[CpFe(Prophos)CN] could be isolated diastereomerically pure. The compounds (R_Fe,R_C)- and (S_Fe,R_C)-[CpFe(Prophos)CN] are configurationally stable at the metal center. There is no diastereomer interconversion, not even at higher temperatures. The carbonyl complexes [CpFe(Prophos)CO]I, [CpFe(Prophos)CO]PF₆, and [IndFe(Prophos)CO]I were prepared in thermal reactions of [CpFe(CO)₂I] and [IndFe(CO₂)I] with (R)-Prophos or in an autoclave reaction of [CpFe(Prophos)I]/NH₄PF₆ with CO under pressure. All the carbonyl complexes are configurationally stable at the metal center. Seven diastereomers were characterized by X-ray crystallography. Including the two diastereomers (R_Fe,R_C)-[CpRu(Prophos)Br] and (R_Fe,R_C)-[CpRu(Prophos)I], a conformational analysis of the M-Prophos chelate ring was carried out, resulting in characteristic differences between major and minor diastereomers.