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7729302 
Journal Article 
The Utility of Sodium Diisopropylamide (NADA): Formation of a New Transition Metalate via Silyl Migration Chemistry, [(eta(5)-Me3SiC5H4)Fe(CO)(PPh3)]Na--(+) (SiFpPNa), and Resulting Thermal Rearrangements of the Complexes SiFpP-CH2SiMe2R (R = H, SiMe3) to SiFpP-SiMe2CH2R 
Munguia, T; Bakir, ZA; Cervantes-Lee, F; Metta-Magana, A; Pannell, KH 
2009 
1 
Organometallics
ISSN: 0276-7333
EISSN: 1520-6041 
28 
19 
5777-5782 
English 
WOS:000270363200025 
A new transition metálate system, [(η5Me 3SiC5H4)Fe(CO)(PPh3) -M+ (SiFpPM; M = Li, Na), was synthesized via treatment of (η5-C5H5)Fe(CO)(PPh3)SiMe 3 with sodium and lithium diisopropylamides (MN(ZPr2); NADA and LDA, respectively). The utility of NADA was far superior to that of LDA, with shorter reaction times, lower reagent concentrations, and higher yields. Infrared spectroscopic analysis of the new ferrates indicated that their stability and utility were dependent upon the tight ion pairs Fe-CO-M; in the presence of coordinating solvents and ionophores the separated ion pairs formed led to the expulsion of the PPh3 and CO scavenging led to formation of the dicarbonylferrate [η5-Me3SiC5H 4)Fe(CO)2]-M+. Hexane was the solvent of choice for formation and use of the ferrates. Reactions of the new ferrates with MeI led to [SiFpP]CH3, whereas reactions with ClCH 2SiMe2R (R = H, SiMe3) did not lead to the expected Fe-C bonded complexes [SiFpP]CH2SiMe2R but to high yields of the rearranged complexes [SiFpP]SiMe2CH2R. The presence of the thermally labile phosphine group readily produces a coordinatively unsaturated 16e species that permits Fe-CH2-SiMe 2R to FeSiMe2CH2R rearrangements (previously observed photochemically with the simple Fp derivatives) to occur thermally. © 2009 American Chemical Society.