Ylid complexes

Figure 4.19 Synthesis of gold ylid complexes, including gold(II) compounds with metal-metal...

In contrast to the results obtained in reactions of M—CF3 complexes with BF3 (see Section III,B,1), the reaction of the perfluoronickelacyclopentane complex 49 appears to proceed via fluoride abstraction, followed by phosphine migration to the electron-deficient carbon to afford the a-fluorophos-phonium ylid complex 50 and related derivatives (117). 

A pronounced chirality effect on the chemical reactivity of ylid complexes is to be expected from propeller-type ligands with a C2 rotation axis. In a first attempt to synthesize pertinent examples, a spirobicyclic ylide 1 was designed (11) and converted into a novel lithio-derivative 2, which on reaction with metal halides yields multi-spiro complexes of unusual geometries ... 

A particularly interesting class are the binuclear ylid complexes [Au2 /i,-(CH2)2PR2 2] which react with Cl2, Br2, or I2 reversibly to give Au—Au bonded Aun alkyls further oxidation leads to Aum complexes without metal-metal bonds (Fig. 18-1-3). 

Dichloro(l, 3-propanediyl)platinum and its bis(pyridine) derivative have been studied by a number of authors. Dichloro(l,3-propanediyl)platinum, and the corresponding substituted 1,3-propanediyl platinum compounds release the parent cyclopropane on treatment with potassium cyanide, potassium iodide, a tertiary phosphine, carbon monoxide, and other ligands.2,6 Reduction by means of hydrogen or lithium aluminum hydride yields chiefly isomeric substituted propanes. Dichlorobis(pyridine)(l,3-propanediyl)platinum in refluxing benzene yields a pyridinium ylid complex, - (CH3CH2CHNC5Hs)-PtpyCla. 

The presence of bases, e.g., sodium hydride or potassium carbonate is essential. Metal(IB)-ylid complexes can be prepared for all three metals , e.g. ... 

A large group of ylid complexes of the type [M (CH2)(CH2)PMe2 3] is also known/ As shown by and NMR spectra, these complexes exist in equi-... 

Me3SiPPh2 gives the ylid complex (CO) MnPPh2C(OSiMe3)R with... 

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