Phenyl metal bonds

The allyl-metal, cyclopropyl-metal, and phenyl-metal bonds are all generally cleaved by electrophilic reagents much more readily than are bonds between the simple alkyl groups and metals. Aralkyl-metal bonds, such as benzyl-metal bonds, on the other hand do not seem to be especially reactive in SE2 substitutions compared with alkyl-metal bonds29. 

X 10 s ) and the phenyl (ki = 1 x lO s ) derivatives to be made at 30 C in 2,2 -diethoxydiethyl ether the cleavage to form the coordinatively unsaturated intermediate occurs more readily for the methyl-manganese bond than for the phenyl derivative. In general, phenyl-metal bonds are stronger than methyl-metal bonds... 

Laser flash photolysis of phenylated Group 14 catenates followed by trapping of the radical intermediates indicates that homolytic cleavage of the metal-metal bond is the... 

Hydrosulfido complexes, 517 bonding, 519 reactivity, 519 structures, 519 synthesis, 518 types, 518 Hydroxamates metal complexes, 505-508 Hydroxamic acid, N-methyl-metal complexes, 507 Hydroxamic acid, phenyl-metal complexes stability, 506 Hydroxamic acids... 

The chromium complexes are proved to be silanediyl complexes, as shown by the silicon-transition metal bond lengths (Table 5) and by the extreme low field shift of the 29Si NMR signals (124.9 and 121.2) at 22 °C for R = H and CH2NMe2, respectively (Table 6). The 29Si NMR shifts of these complexes are temperature-dependent due to the hindered rotation of the phenyl ring and dynamic coordination of the nitrogens to the Si atom. 

In both systems the hydrogen molecule is apparently split into ions, rather than atoms. Weight is lent to this conclusion by the fact that the order of increasing ease of hydrogenolysis of phenyl derivatives is Ca, Li, Na, K, Rb, and Cs this is also the order of increasing polarity of the carbon-metal bond. 

The mass spectra of certain metal carbonyl complexes of triphenyl-phosphine and l,2-bis(diphenylphosphino)ethane (Pf-Pf) have been investigated 48>. Besides the usual stepwise loss of carbonyl groups, cleavage of the phosphorus-carbon bond occurs. Thus triphenylphosphine complexes exhibit cleavage of the phenyl-phosphorus bond after all carbonyl groups are lost. The 1,2- bis(diphenylphosphino)ethane complexes (e.g. (Pf-Pf)[W(CO)5]2 and (Pf-Pf)M(CO)4) exhibit elimination of the ethylene bridge between two phosphorus atoms. 

The reduction equivalents required for conversion of N2 to NH3 are obtained from the carbanionic phenyl groups bonded to nickel in 14 (biphenyl formation). The Ni atoms, which are still present as Ni(0), i.e., in the form of metallic nickel after hydrolysis, only function as agents for the transfer of electrons from C6H5 to N2. In this respect, the hydrolysis of... 

During the oxidative addition of allylic phenyl sulfides to palladium(0) complexes to give / -allyl-/ -sulfide complexes, 41 (R -R = H or Me, R H, Me, or Ph), reactants having y substituents (R or R ) require more than 20 times as long for completion of the reactions than those with either no or a or substituents. The reaction, therefore, probably occurs by initial electrophilic attack by the palladium on C-y, expulsion of the SPh unit, and formation of a metal-metal bond (63). 

With the use of suitable bridging ligands [bis(diphenylphosphinomethyl)phenyl-phosphine, bis(biphenylphosphinomethyl)phenylarsine, and 2,6-bis(diphenylphos-phino)pyridine], it is possible to construct nearly linear arrays of three metal-metal bonded centers " ... 

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