Ketone ligands binding modes

Tetrahydrofuran (THF), acetone, water, and ethanol are much less strongly ligating and are widely used. Early transition metal complexes can be very sensitive to solvents containing labile protons, but this depends on the case. All of these solvents can act as weak ligands, and their complexes can be synthetically useful. Ketones usually bind in the mode via O, as in 4.22, but can also bind in the V mode via both C and O, as in 4.23 (Eq. 4.S9). The latter is favored by low steric hindrance and by a strongly back-donating... 

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