Bidentate 2,3-diaminobutane

The first examples of metallated phosphine-functionalized dendrimers that were suitable as homogeneous catalysts were reported by Reetz et al. [42], DAB-based phosphino dendrimers were synthesized from the commercially available DAB-polypropylene imine dendrimers (DAB = 1,4-diaminobutane) via a double phosphination of the amines with diphenylphosphine and formaldehyde. These dendrimers were loaded with Pd(II) centers by the reaction of the phosphine-functionalized dendrimer with [Pd(Me)2(tmeda)] (tmeda = tetramethylethylenediamine), in which the diphenylphosphino end groups act as a bidentate ligand (Scheme 6). 

The synthesis and reactivities of substituted aliphatic bidentate complexes are similar to the reactions of analogous ethylenediamine complexes. Basolo and co-workers prepared619 and studied the rates of chloride aquation555 of a variety of trails-[Rh(N N)2 Cl2 ]+ complexes (NN = meso-bn, where bn = 2,3-diaminobutane (+)-bn, and tetrameen—both cis and trans isomers) the rate of chloride release is not dramatically dependent on the nature of the aliphatic amine ligand. 

A stopped-flow spectrophotometer was used to obtain the kinetics data for the reaction of a nickel(II) complex NiL2 of a substituted bidentate diamine ligand (L = tetmeen = 2,3-dimethyl-2,3-diaminobutane) with cyanide ion. The reaction is biphasic one diamine ligand is replaced by two cyanide ligands, then the second diamine ligand is replaced ... 

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