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Amide, thiolate, and alkoxide ligands

Alcohols and thiols also react rapidly with most amides to give alkoxide or thiolate ligands with liberation of amine. Steric factors can be sufficiently important to limit this exchange (e.g. equation 66) and in some instances redox reactions may occur (equation 67).212 Salt formation is also possible in some cases (equation 68).213... [Pg.180]

Monomeric amide, alkoxide and thiolate derivatives of germanium(II), tin(II) and lead(II) are only obtained with very sterically crowded ligands. Thus, bis(2,2,6,6-... [Pg.220]

Such a charge transfer from the ligated arene can lead to (a) nucleophilic addition or substitution, (b) electron transfer, and (c) proton elimination/transfer, thus revealing the dose relationship between all of these processes. The reactivity of the arene ligands towards nudeophiles in (arene)ML complexes depends on the electrophilidty of the metal fragments [MLn], this increasing in the order [Cr(CO)3] < [Mo(CO)3] [FeCp]+ < [Mn(CO)3]+ [2]. For example, in (arene)FeCp+, which is widely used for synthetic purposes, a chloro or nitro substituent on the arene is readily substituted by such nudeophiles as amides, eno-lates, thiolates, alkoxides, and carbanions [45]. [Pg.456]

It is clear that electron-withdrawing alkoxides in M(NAr)(CHR)(OR )2 complexes dramatically increase the rate of reaction of an olefin with the M=CHR bond. In fact, no other X ligands in M(NAr)(CHR)X2 complexes are as successful as alkoxides for sustained metathesis activity, [66] either because they are not bulky enough to stabilize an electron deficient metal center and prevent bimolecular decomposition (e.g., halides) or because they donate too much electron density to the metal in a a and/or Ji fashion (e.g., amides or thiolates). A recent example is Mo(NAr)(CHR)(diamide) where the diamide is a N,N -disubstituted-2,2 -bisamido-l,r-binaphthyl ligand no ready reaction was observed between this complex and ethylene or even benzaldehyde. [108] Alkylidene complexes are now known for all metals in groups 4, 5, and 6, plus rhenium. For example, it was shown that Cp2Ti(CH2) could be trapped... [Pg.221]


See other pages where Amide, thiolate, and alkoxide ligands is mentioned: [Pg.2]    [Pg.71]    [Pg.2]    [Pg.71]    [Pg.390]    [Pg.432]    [Pg.432]    [Pg.577]    [Pg.547]    [Pg.432]    [Pg.147]    [Pg.1386]    [Pg.108]    [Pg.41]    [Pg.333]    [Pg.41]    [Pg.333]    [Pg.363]    [Pg.598]    [Pg.2059]    [Pg.43]    [Pg.402]    [Pg.2]    [Pg.155]    [Pg.415]    [Pg.421]   
See also in sourсe #XX -- [ Pg.71 , Pg.72 , Pg.73 , Pg.74 , Pg.75 , Pg.76 ]




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Amide ligands

Thiolate

Thiolates

Thiolation

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