Condensation of 1,2-Diamine

The common synthetic route to bismaleimides or maleimide functionalized oligomers is the condensation of diamines or amino-terminated oligomers with maleic anhydride. Another possibiUty is the use of an AB-type monomer of the following general formula to build the polymaleimide, where X represents a functional group that can be employed in condensation reactions. 

Macrocycles have been prepared by formation of macrocyclic imines as well as by using variations of the Williamson ether synthesis ". Typically, a diamine or dialdehyde is treated with its counterpart to yield the Schiff s base. The saturated macrocycle may then be obtained by simple reduction, using sodium borohydride, for example. The cyclization may be metal-ion templated. In the special case of the all-nitrogen macrd-cycle, 15, the condensation of diamine with glyoxal shown in Eq. (4.14), was unsuccess-ful ... 

Similar chemistry was applied by Heeg and co-workers in their synthesis of substituted quinoxalines 244, which were prepared by condensation of diamine 243 with 1,2-dicarbonyl compounds <00JHC1273>. Vagg utilized analogous chemistry to synthesize phenazines as well as quinoxalines (Section 6.2.8.1). 

Condensations of diamines with dicarbonyl compounds are a fruitful source of imino macrocycles. Condensations can be 2 2 with diamines to form tetraimine macrocycles, or 1 1, with additional heteroatoms present for the amine and/or carbonyl components, to form diimine macrocycles, as for (9) and (10) formed from 1,2-dicarbonyl compounds. 

Other examples of macrocycles formed by 1 1 condensations of diamines with dicarbonyl compounds, with additional donor atoms present for the amine or carbonyl compound, include an extensive family with 2-aminobenzaldimino chelate rings, such as (20), and those formed from (7). 

Fig. 9.27. Condensation of diamines with dicarbonyl compounds (and/or their hydrates) to give N heterocycles. Double imine formation yields quinoxalines (B), double enamine formation leads to dimethylpyrrole (D).

Condensations of Diamines with Saturated Electrophilic Carbon. 199... 

Cu-diimine macrocycle compounds (31) are formed by Jaeger template condensations of diamines with acyl-substituted /3-keto imines (30) (Scheme 9). The acyl substituents on the macrocycles are labile and undergo a variety of reactions. Reaction with trifluoromethyl sulfonate produces reactive methoxy ethylidene diimine compounds (32), which react with amines to form saddle-shaped cyclidenes. With bulky substituents these compounds have a hydrophobic void above the metal ion which can accommodate a guest molecule, an effect enhanced when the... 

Several Schiff-base ligands derived from the condensation of diamines and 1,3-diones were employed as tetradentate ligands for Zr. For example, the complexes ZrCl2[OCRCHC-(Me)NCH2]2 (R = CF3, Me) were derivatized and subsequently the salt... 

A diamine solution in water and a diacid chloride solution in hexane are prepared. A porous substrate membrane is then dipped into the aqueous solution of diamine. The pores at the top of the porous substrate membrane are filled with the aqueous solution in this process. The membrane is then immersed in the diacid chloride solution in hexane. Because water and hexane are not miscible, an interface is formed at the boundary of the two phases. Poly condensation of diamine and diacid chloride will take place at the interface, resulting in a very thin layer of polyamide. The preparation of composite membranes by the interfacial in situ polycondensation is schematically presented in Fig. 3. 

In contrast to the condensation of diamine with acetoacetate (Chapter 76), base-catalysed cyclization of the product of acetoacetate with one amine group gives the benzodiazepine-2-one [2327], The anilinopyrrole (48.3) is cyclized to form a new imidazole ring when heated with PPA (Chapter 54), but when PPA... 

The Wurlan Process [88] (i.e., the condensation of diamines and diacid chloride in the presence of wool fiber)... 

Nylons can be made from the condensation of diamines and dibasic acids, or from the condensation of amino acids, which contain both amine and acid functional groups in a single molecule. For example ... 

Aliphatic polyamides are produced commercially by condensation of diamines with dibasic adds, by self-condensation of an amino acid, or by self-condensation of an amino acid, or by ring-opening polymeri2ation of a lactam [14,40,41]. To obtain polymers of high molecular weight, there should be stoichiometric equivalence of amine and acid groups of the monomers. For amino acids and lactams the stoichiometric balance is ensured by the use of pure monomers for diamines and dibasic acids this is readily obtained by the preliminary formation of a 1 1 ammonium salt, often referred to as a nylon salt. Small quantities of monofunctional compounds are often used to control the molecular weight. 

The synthesis of novel quinoxaline derivatives was key in the study of inhibitors of Pirn kinases. This structure-activity relationship (SAR) study found several promising molecules that demonstrated antiproliferative properties against solid cancer cell lines (PAl, PC3, and DU145). The synthesis of these compounds relied on the previously optimized condensation of diamines with a-halogenated carbonyls followed by oxidation to provide the aromatic bicycle. ... 

Fig. 22 Condensation of diamines with a dicarbonyl compound. The size and nature of the macrocycies thus obtained are strongly related to the relative overall proportion of the two reactants, the chain length of the diamine, and the template cation used.

Nylons are prepared by (1-a) eondensation of diamines and dibasie acids or (1-b) condensation of diamines and dibasic acid chlorides, (2) ring-opening polymerization of eyelie lactams, (3) self-condensation of bifimctional amino acids, etc. Some important polymerization reactions and citations to the reviews covering them are given in Table 2. 

The first synthesis of SFs-substituted benzimidazoles was described in an Asahi Glass patent (04JPP059452). Protected N-acetyl-4-SF5-aniline (58) was converted into the protected nitroaniHne 59, which was then quantitatively deprotected to nitroaniline 60, reduction of which provided 1,2-diamino-4-SF5-benzene 61 in 100% yield. Condensation of diamine 61 with formamide or A/,N-(bis)methoxycarbonyl-S-methylisothiourea (62) resulted in the formation of the corresponding S-SFs-benzimidazole 63 or S-SFs-substituted methyl (2-benzimidazolyl)carbamate 64 (Scheme 15). 

Polyamides contain the amide group —NH—CO— and can be classified in two homologous series. In the Perlon series, monomeric and repeat units are identical, since these polyamides occur either by the polymerization of lactams (cyclic amides) or the polycondensation of co-amino carboxylic acids. In contrast, the polyamides in the Nylon series are formed by the poly condensation of diamines and dicarboxylic acids Thus, two monomeric units form one repeat unit. 

In contrast to the poly(enamine-ketones) prepared by Imai e al. the methyl substituted poly(enamine ketones), J 2, prepared from the condensation of diamines and bis-acetylacetylarenes, were found to be hydrolytically stable and thermally stable from 257 to 340 C, When a linear and rigid aromatic bis(1,3-diketone) was condensed with alkaline dieamines with ten or more carbons or with rigid aromatic diamines, thermotropic liquid crystalline materials were obtained. The monomers and polymers have much higher solubilities and lower transition temperatures as compared with liquid crystals containing only aromatic hydrocarbon rings of similar structures. 

Figure 1. Condensation of diamines with diiodides leading to diaza-crown ethers.

The direct condensation of diamines with intermediate 9 generally does not lead selectively to the desired product. The latter is therefore first cydized to a reactive tetrachloroisoindolinone precursor of type 6 or 7 by reacting with such reagents as alcoholates, amines or sodium sulfide, before being subjected to facUe condensation with a diamine. 

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