Monoalkylation diamines

Treatment of enantiomerically pure (R,R)- and (A,A)-l,2-bis(pentafluorophenyl)ethane-l,2-diamines with thionyl chloride gave the corresponding thiadiazolidine 1-oxides in high yield <2004BCJ1001>. A series of Aralkyl-substituted thiadiazolidine 1,1-dioxides 171 were also prepared from the starting 1,2-diamine 170 by treatment with sulfamide followed by a regioselective monoalkylation (Scheme 26) <2005BML4212>. 

Unsymmetric diamines can be monoalkylated regioselectively if the reactivity of both amino groups is substantially different. If the two groups are similar, however, such reactions are usually difficult to perform, and low yields are usually obtained (Scheme 6.6). 

Unsymmetric diamines can sometimes be acylated selectively at one amino group only, if one of the amino groups is sterically or electronically deactivated. If the difference in reactivity is only small, acylating agents of low reactivity will usually be required. Some polyamino heteroarenes can be monoacylated or monoalkylated with astonishingly high regioselectivity (Scheme 7.13), which is, however, difficult to predict. 

Alkylation of amines usually proceeds more slowly than acylations, and alkylating reagents can usually be thoroughly mixed with an amine before reaction is complete. Diamines or polyamines can therefore be transformed into mixtures of the statistically expected amounts of alkylated derivatives (Scheme 10.17). The use of CsOH as base has been found to be particularly conducive to the formation of monoalkylated products [72]. Some polyamines have also been monoalkylated selectively after complexation with Zn(II) [73],... 

Such complexes can in fact, as well as in principle, exhibit significant antitumor activity. We report here the synthesis, characterization, and antitumor activity of two broad classes of complex having structure II, those where the positively charged ligand is a monoprotonated (or monoalkylated) diamine and those where it is a monoprotonated amino-olefin. 

Prior to our work, there had been few reports of platinum complexes bearing monoprotonated (or monoalkylated) diamines as ligands. To our knowledge, only three complexes having this structure have been characterized. Terzis ( ) prepared and determined the crystal structure of trichloro(9-methyladeninium)... 

Waterborne polyurethane resins are produced from maleinised monoglyceride (MMG) of sunflower oil, hydroxy-terminated polybutadiene, toluene diisocyanate and ethylene diamine. The carboxylic acid groups of MMG are neutralised by triethyl amine, making the resin water dispersible. The monoalkylated castor oil (MCO) or dehydrated castor oil (DCO) is treated with a polyether glycol at 120°C, followed by the addition of IPDI and DBTDL. To obtain a series of aqueous polyurethanes, butane diol and dimethylol propionic acids (DMPA) are added and the mixture heated to 70°C for two hours to produce a NCO-terminated pre-polymer which forms salt with triethylamine, giving a water-soluble polymer. The reaction mixture is dispersed in water and a chain extender, ethylene diamine, is added. Two aqueous polyurethanes, MCPU and DCPU, are finally obtained from MCO and DCO, respectively. 

Compounds containing both an isocyanate and a carbamoyl chloride group (for example, 179) have been prepared by reacting monoalkyl a,co-diamines (for example, 178) with phosgene [111, 112]. 

The norbornene concept was further developed by NASA Lewis Research Center and culminated in the so-called PMR-concept, a novel class Of addition-type polyimides formed by in situ polymerization of monomeric reactants. 5 jhe reaction sequence36-37 involves aromatic diamine, S-norbornene-2,3-dicarboxy1ic acid monoalkyl ester and dialkyl ester of an aromatic tetracarboxylic acid which produces methanol, water, and the following intermediates [6]. 

Akamatsu et al. has described a solid-phase synthehc route via selective monoalkylation of o-phenylenediamines with polymer-supported alkyl halides [26]. Subsequent cyclization of the diamines with various aldehydes afforded solid-supported benzimidazoles. Cleavage from the resin in the presence of trifluoroacetic acid (TFA) afforded benzimidazoles in good yields (Scheme 5). 

C. Hofmann Alkylation—Monoalkyl Derivatives of Diamines 13-3. Preparation of Monomethylethylenediamine... 

The preparation of monoalkyl derivatives of diamines represents something of a synthetic problem. Procedure 13-3 involves acetylation of ethylenediamines under mild conditions to the monoacetyl ethyl-enediamine, protection of the second amino group by a Hinsberg reaction with benzenesulfonyl chloride, followed by N-alkylation of the acetamido group, and recovery of the iV-alkylethylenediamine by acid hydrolysis [15]. 

---