1,3-Diaminopropanes

If one end of a chelate ring on an octahedral complex is detached from the metal, the five-coordinate transition state can be considered as a fluxional molecule in which there is some interchange of positions. When the chelate ring reforms, it may be with a different orientation that could lead to racemization. If the chelate ring is not symmetrical (such as 1,2-diaminopropane rather than ethyl-enediamine), isomerization may also result. For reactions carried out in solvents that coordinate well, a solvent molecule may attach to the metal where one end of the chelating agent vacated. Reactions of this type are similar to those in which dissociation and substitution occur. 

Synthesis of hindered morpholinones or piperazinones from ketones (such as acetone) and 2-amino-2-methyl-l-propanol or 1,2-diaminopropanes. 

Here pn is 1,2-diaminopropane and bn is 2,3-diaminobutane. Decomposition of the amine cation radicals obtained by photooxidation of the ligands en, bn, and pn have been discussed by Moeller. The products of Co(en)33+ photolysis can be satisfactorily explained by postulating that carbon-carbon bondbreaking is the principal step in decomposition of the cation radical H2NCH2CH2NH2t.58 Presuming a similar mechanism to obtain in photoreduction of Co(pn)33+, there are then two possible reaction pathways leading to different products. 

The conversion of 2,4-bis(4-cyanophenyl)-6-dimethylamino-13,5-triazine into the corresponding diaryl cyclic diamidine via reaction with an excess of 1,2-diaminopropane saturated with hydrogen sulfide has been reported. 2,4-Bis(4-cyanophenyl)-133-triazine is resistant to cyclization in reacting with 1,4-diaminobutane under similar conditions and affords 2,4-bis[4-[V-(4-aminobutyl)thiocarbamoyl]phenyl]-133-triazine <99TL2841>. 

Equatorial substituents on the C atoms of coordinated 1,3-diamino-propane should be stabilized in the same manner as the 1,2-diaminopropane system and axial substituents on the 1 and 3 C atoms should interact strongly with the axial substituents on the Co atom. Substituents on the N atoms... 

Diaminopropane (called 1,2-Diamino-propan or Propylendiamin in Ger), CH3.CH(NH2).CH2.NH2 exists as d-form, 1-form dl-form all of which form numerous, cryst salts, some of which are unstable on heating (Ref 1)... 

N -Nitro-1, 2-diaminopropane [called N1-Nitro-1,2-Propane diamine in CA and 2-Amino... 

Complexes [VL3]X2 (L = en, 1,2-diaminopropane, 1,3-diaminopropane X = C1, Br, I) and [V(dien)2]X2 were prepared by mixing ethanolic solutions of amine and of vanadium(II) halide. The magnetic moments (3.66-3.91 BM) and electronic spectra were typical of octahedral vanadium(II) and there was no halogen coordination.65... 

Although earlier attempts to isolate chromium(II) complexes of various bidentate amines from aqueous solutions produced chromium(III) complexes and hydrogen, the predominantly non-aqueous methods outlined in Scheme 10 provide complexes of ethylenediamine (en), 1,2-diaminopropane (pn), 1,3-diaminopropane (tmd), l,2-diamino-2-methylpropane (dmp), jVjA-dimethylethylenediamine (NNdmn) and N, N -dimethylethylenediamine (NN dmn) (Table 11). In general, ethanol is a suitable solvent but with some amines it is necessary to dehydrate the halide with 2,2-dimethoxypropane (DMP) and dry the ethanol carefully to prevent hydrolysis and oxidation. 

The potentially six-coordinate ligands (edta)4- and (pdta)4" (H4edta = N,N,N, N tetrakis(2-ethanoic acid)-l,2-diaminoethane, H4pdta = N,N,N, iV -tetrakis(2-ethanoic acid)-1,2-diaminopropane) add to dimeric molybdenum(V) centres to form complexes such as [Mo202Y2(edta)]2- and [Mo02Y2(pdta)]2- (Y = O, S) 425-429 The structure of... 

Since many ligands are organic compounds which have possibilities for isomerism, the resulting complexes can show isomerism from this source. Examples of isomeric ligands are 1,2-diaminopropane ( propylenediamine, pn) and 1,3-diaminopropane C trimethylenediamine, tn) or ortho-, meta-, and pcra-toluidine fCH3C6H4NH2). 

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