Tris carbonyl chelate complexes derived

Chelate Complexes Derived from Tris(triphenylphosphine)rhodium(l) Carbonyl Hydride and Bisphosphines... 

As indicated in the introduction, bis-l,3-diphenylphosphino-propane (dppp) and bis-l,2-diphenylphosphinoethane (dppe) were reacted with tris(triphenylphosphine)rhodium(II) carbonyl hydride in toluene-deuterobenzene solution to derive cis-chelate complex hydroformylation catalysts. These complexes were expectedly non-selective terminal hydroformylation catalysts for 1-butene hydroformylation (see Table I) because of their cis-stereochemistry. They were also somewhat less active due to their specific structural features. The structure of these complexes in solution was studied in detail by P-31 NMR spectroscopy. 

A variety of monoanionic N,0-chelate complexes have been described. These include ligands derived from phenolic diazo compounds, a variety of Schiff-base derivatives, aldehyde hydrazone ligands,762 thiazolidin-4-ones,763,764 and salicylideneamino-3,5-dimercapto-l,2,4-tri-azoles.760 Similarly, the complexes Ti(OPr )4 (NHC(0)R) (R = Me, Ph, NC5H4, n 4) are thought to be coordinated via the carbonyl group of the amide functional group.765... 

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