Ethylenediamine, condensation with

Other examples of template cyclization reactions leading to macrocycles with amine double bonds that can be reduced to the fully saturated systems will be discussed later. Often, without the template ion, small 1 1 cyclizations take place. In the case of the Curtis reaction, a seven-membered ring was formed without the template ion (Montecatini, 1968). Ethylenediamine condensed with mesityl oxide or with other a,/3-unsaturated ketones to give tetrahydro-l,4-diazepines without the template ion (Elguero et al., 1969 Guareshi, 1894 Mushkalo and Shokol, 1960). However, in the case of reactions of rigid arylideneacetone or benzylideneacetophenone with ethyl-... 

On oxidation by potassium hexacyanoferrate(III) adrenaline is converted into adrenochrome which then condenses with ethylenediamine ... 

Ethylenediamine (15 g, 0 5 mol) was added dropwise to 100 ml 9B-100% formic acid in a two-necked 500 ml flask, fitted with an addition tube and reflux condenser with drying tube, cooled in an ice-bath. After complete addition of the base, 53 g of benzaldehyde (0.5 mol) was added in one lot. The ice-bath was removed and the flask was heated to the refluxing temperature. The initial rate of carbon dioxide evolution was too rapid to measure. After twenty minutes, the rate was circa 100 ml per minute and decreased rapidly to B ml per minute in one hour. Heating at reflux was continued for 35 hours. 

The complex [Co(NH3)5(OS02CF3)]2+ undergoes triflate substitution by cyanate and condensation with acetone to form the unusual bis-bidentate imine complex (213)917 in a reaction reminiscent of the classic Curtis condensation of acetone with ethylenediamine. Apart from the novelty of the synthesis, the reported crystal structure was only the second of a CoN6 complex bearing a cyanate ligand. 

Bis(ethylenediamine)gold(III) chloride reacts with /3-diketonates in aqueous base via Schiff base condensation to form complexes of gold(III) with a 14-membered macrocyclic tetraaza ligand such as (292).1711-1713 The X-ray structure showed the cation to be nearly planar. Delocalization of -electrons within the six-membered /3-diketonate rings was indicated by the observed pattern of C—C and C—N distances. Open-chain tetraaza ligand complexes in which condensation of only one /3-diketonate has occurred, can be isolated as intermediates in this reaction. They may be used for further condensation with a different /3-diketonate. Oxidation of this complex with trityl tetrafluoroborate introduces a double bond in position C2C3.1712,1714... 

Which of the following will give a polymer when condensed with adipic acid (a) ethanol (b) ethylene glycol (c) glycerol (d) aniline or (e) ethylenediamine ... 

The synthesis of the hrst of these agents starts with the dye intermediate leucoquinizarin (35-1), the reduction product of the dihydroxyanthraquinone, quinizarin. Condensation with A-(2-hydroxyethyl)ethylenediamine (35-2) leads to the corresponding bis imine (35-3). Air oxidation may be visualized as starting at the hydroquinone-like central ring bond reorganization will lead to ametrantrone (35-4) [35]. 

Diiminodiphosphines. The aldehyde PCHO cleanly condenses with ethylenediamine in refluxing ethanol to afford the off-white dii-mine, en = P2. This ligand reacts readily with most metal ions affording derivatives in a variety of geometries as shown by X-ray crystallographic and spectroscopic studies (6). 

The second method makes use of the modified Streckter synthesis [9], First, hydrogen cyanide is reacted with formaldehyde to produce cyanohydrine. The latter compound is condensed with ethylenediamine to produce ethylenediamine tetracyanomethylene. Hydrolysis of the this compound produces the free acid. These reactions are schematically represented by Scheme 2. 

Fe(en)3]Cl2 (en = ethylenediamine) The complex forms when, under anhydrous and anaerobic conditions, an excess of ethylenediamine is added to a solution of iron(II) chloride in ethanol. The product may be condensed with acetone, producing a tetraazacyclotetradecadiene macrocycle by way of a metal template reaction (88). [Fe(en)3]Cl3 is produced in a similar manner by reacting anhydrous iron(III) chloride with ethylenediamine (89). 

Macrocycles with 2 nitrogen and 3 sulfur donors have been prepared (14) by a template synthesis in which the dialdehyde (XCI) is condensed with primary diamines, e.g., ethylenediamine gives XCII in boiling acetonitrile containing Fe(II) perchlorate. The reaction is typical of template condensation between carbonyl compounds and primary amines. An unusual monanionic macrocyclic ligand was produced (2) when formaldehyde was condensed with the hydrazine (XCIII) instead of a primary amine in the presence of Ni(II) salts, and complexes XCIV have been characterized. 

The labile Co2+ ion was made to react with three molecules of ethylenediamine (en), to give the octahedral [Con(en)3]2+ complex, which was then oxidised by air to the inert [Cora(en)3]3+ (Fig. 8, step i). Then, Schiff base condensation with six... 

Ethylenediamine has been condensed with a variety of compounds to produce 1,4-diazepine systems. For example, use of a (8-diketone such as acetylacetone gave 164 or 165.176,177 Other (8-diketones178,178 behave in a similar manner. The reaction of malondialdehyde diacetal with 2V,AT -diphenyl ethylenediamine in the presence of perchloric acid also took a similar course to give 166.170 Substituted malon-... 

One of the few examples of formation of the pyrazine ring as the last step in the synthesis of imidazo[4,5-fe]pyrazines (504) involves the reaction of biacetyl with the diamine (503) generated in situ from the 4-nitro-5-amino compound (502) (70TL1013>. Another synthesis involving the use of an imidazole is the condensation of ethylenediamine (505) with (506) to give the perhydro derivative (507). 

As has been demonstrated in Section 3.1.2.4, complexation of amino groups offers a quite different concept for reversible protection. Making use of this principle, the coordination of chromium carbyne complexes with amino acids was described as a new amino protection. Similarly, bis(ethylene-diamine)cobalt(III) complexes of amino acids constitute a new interesting method for protection which recently was extended to the development of a new type of anchoring in solid-phase synthesis (Scheme 69). First, a t-BOC amino acid is condensed with the aquabis(ethylenediamine)cobalt(lII) complex of p-aminomethylbenzoic acid. The handle obtained in this way is then linked to aminomethyl polystyrene to give the anchored amino acid (69). Due to the sufficient stability of the complex toward... 

Ethylenediamine undergoes catalytic self-condensation (with loss of 2 Nil,) to give piperazine and subsequently (by dehydrogenation)pyrazine (Pt—AFO, 400°C —38% pyrazine)." ... 

As a 1,2-diketone, 4,7-phenanthroIine-5,6-dione reacts readily with ethylenediamine and 5,6-diamino-4,7-phenanthroline to give pyrazine derivatives. Several related condensations have also been reported. It also condenses with enamines, trialkyl and dialkyl phosphites, and guanidine carbonate. ... 

Figure 1. Condensation reaction of metal(n)-ethylenediamine complexes with acetone. (Only one of the products is shown.)...

Tetracyclic metal complexes. The 14-membered macrocycle (3) can be prepared by the condensation of ethylenediamine (2) with phenylazomalondialde-hyde (1) in the presence of this nickel salt. Divalent copper salts can also be used. 

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