Meso-2,3-Diaminobutane

Five-membered chelate ring of meso-2,3-diaminobutane is puckered with one methyl group equatorial and one axial. 

Table 1. Formation constants of some metal complexes with RS-diaminobutane (meso-DAB) and RR/SS-diaminobutane (rac-DAB) and the corresponding tetraacetic acids (DABTA)...

Another example studied is the isomers of the complex derived from racemic and meso forms of 2,3-diaminobutane. The complex is depicted below. With the racemic addition of Eu[(+)fpc]3 gives the two sets of resonances due to R,R- and 5,5-diastereomers. With meso form, a doubling of each spectral peak was observed. The doubling is due to the presence of a meso plane in the molecule which makes each half of the molecule enantiotropic. 

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. 

Diaminobutane, CH3.CH(NH2)XH(NH2).CH3 forms many salts which are unstable on heating exists as meso form, bp 59-60° at 60mm Hg, and as ragem form, bp 57-58° at 60mm Hg (Ref 4)... 

Tertiary Amines. The photolysis of trlethylamine has been studied by Pfordte and Leuschner (212) and by Allan and Swan (218). They identified the dehydrodimer N,N,N, N -tetraethyl-2, 3-diaminobutane (meso and racemic) and tetraethylhydrazine as well as N,N -diethyl-2,3-diaminobutane (218). 

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