Amines 2,4-dinitrophenyl

Appllca.tlons. Various A/-derivatives of amino acids (qv) are resolvable on BSA columns. These /V-amino acid derivatives include ben2enesulfonyl-, phthalimido-, S-dimethylarnino-l-naphthalenesulfonyl- (DANSYL-), 2,4-dinitrophenyl- (DNP-), and 2,3,6-trinitrophenyl- (TNP-) derivatives (30). Amines such as Prilocain, ( )-2-(prop5lamino)-(9-propiono-toluidide, a local anesthetic (Astra Pharm. Co.), are also resolved on BSA. The aromatic amino acids DL-tryptophan, 5-hydroxy-DL-tryptophan, DL-kynurenine [343-65-7] C qH 2N 2 3 3-hydroxy-DT.-kynurenine [484-78-6] and dmgs... 

Another example of the analogy between pyrazole and chlorine is provided by the alkaline cleavage of l-(2,4-dinitrophenyl)pyrazoles. As occurs with l-chloro-2,4-dinitrobenzene, the phenyl substituent bond is broken with concomitant formation of 2,4-dinitrophenol and chlorine or pyrazole anions, respectively (66AHC(6)347). Heterocyclization of iV-arylpyrazoles involving a nitrene has already been discussed (Section 4.04.2.1.8(i)). Another example, related to the Pschorr reaction, is the photochemical cyclization of (515) to (516) (80CJC1880). An unusual transfer of chlorine to the side-chain of a pyrazole derivative was observed when the amine (517 X = H, Y = NH2) was diazotized in hydrochloric acid and subsequently treated with copper powder (72TL3637). The product (517 X = Cl, Y = H) was isolated. 

The Zincke reaction is an overall amine exchange process that converts N- 2,A-dinitrophenyl)pyridinium salts (e.g, 1), known as Zincke salts, to iV-aryl or iV-alkyl pyridiniums 2 upon treatment with the appropriate aniline or alkyl amine. The Zincke salts are produced by reaction of pyridine or its derivatives with 2,4-dinitrochlorobenzene. This venerable reaction, first reported in 1904 and independently explored by Konig, proceeds via nucleophilic addition, ring opening, amine exchange, and electrocyclic reclosure, a sequence that also requires a series of proton transfers. By... 

A regioselective synthesis of 2-amino[l, 2,4]triazinones 708 was reported (82JHC1583 83JHC1671) by reaction of 706 with 0-(2,4-dinitrophenyl)-hydroxylamine 707 as an amino transfer agent. Subsequent reaction of 708 with ammonia or amines, followed by ring closure with formic acid, provided 709. 

The number of reactions that fit into this second class are manifold. Some typical examples are the amine-catalyzed reactions of 2,4-dinitrochlorobenzene with n-butylamine in chloroform (k"/k = 2.59 l.mole-1)23, with allylamine in chloroform (k"jk — 4.60 l.mole-1)24 and with allylamine in ethanol (k"fk =0.36 l.mole-1)25 and the amine-catalyzed reaction of p-nitrofluorobenzene with piperidine in polar solvents (k"/k < 3.2 l.mole-1)26. A typical example of a strongly catalyzed system is the reaction of 2,4-dinitrophenyl phenyl ether with piperidine in 60 % dioxan-40 % water27. 

If one limits the consideration to only that limited number of reactions which clearly belong to the category of nucleophilic aromatic substitutions presently under discussion, only a few experimental observations are pertinent. Bunnett and Bernasconi30 and Hart and Bourns40 have studied the deuterium solvent isotope effect and its dependence on hydroxide ion concentration for the reaction of 2,4-dinitrophenyl phenyl ether with piperidine in dioxan-water. In both studies it was found that the solvent isotope effect decreased with increasing concentration of hydroxide ion, and Hart and Bourns were able to estimate that fc 1/ for conversion of intermediate to product was approximately 1.8. Also, Pietra and Vitali41 have reported that in the reaction of piperidine with cyclohexyl 2,4-dinitrophenyl ether in benzene, the reaction becomes 1.5 times slower on substitution of the N-deuteriated amine at the highest amine concentration studied. 

The dinitrophenyl derivatives are reduced by titanium(III) chloride in acidic medium in the first step of the reaction to the corresponding aromatic amines these are then diazotized and coupled with N-(l-naphthyl)-ethylenediamine to yield an azo dye (cf. Fig. 21). 

The cycloaddition between a nitrilimine 319 and an aroyl substituted heterocyclic ketene aminal 318 has been found to be stepwise, involving an initial nucleophilic addition of 318 to 319 followed by intramolecular cyclocondensation of the intermediate 320 providing fully substituted pyrazole 321 (Eq. 36) [92]. When Ar was the 2,4-dinitrophenyl group, the intermediate 320 was isolable and required forcing conditions (xylene, reflux, 10 h) to undergo cyclization ... 

Dinitrophenyl derivatives. The halogen atom in 2 4-di-nitrochlorobenzene is reactive and coloured crystalline compounds (usually yellow or red) are formed with primary and with secondary amines ... 

Yet another situation is observed in the 2,4-dinitrophenyl phosphate dianion. A significant effect of amines on the rate of decomposition is admittedly observed however, typical 2nd order kinetics, lower enthalpy of activation compared with spontaneous hydrolysis, and strongly negative AS values (see Table 3) indicate an Sn2(P) reaction. Surprisingly, the reaction rate remains unaffected by the basicity of the amine, even when its pKa value changes by 8 units. 

Amines, amino acids, peptides 2,4-dinitrophenyl hydrazone PRE-CD with +1.10 217... 

An easily accessible DA CSP derived from L-A-(2-naphthyl)valine (80) was used to separate appropriately derivatized amines, amino alcohols and thiols, derivatization consisting of N-, O- and 5-acylation with 3,5-dinitrobenzoyl chloride or 3,5-dinitrophenyl... 

The Zincke reaction is an overall amine exchange process that converts N- 2,A-dinitrophenyl)pyridinium salts, known as Zincke salts, to A -aryl or A -alkyl pyridiniums upon treatment with the appropriate aniline or alkyl amine. 

Pentryl (152) is obtained from the action of fuming nitric acid or mixed acid on Ai-(2,4-dinitrophenyl)ethanolamine, itself obtained from the reaction of 2,4-dinitrochlorobenzene with ethanolamine. Another route to pentryl (152) involves the nitration of A-phenylethanol-amine, which is obtained from the reaction of aniline with ethylene oxide. ... 

N20.09%, yel ndl(w/alc), mp 196°, sol in 20% HC1 dil alkali. Prepd by boiling with IN NaOH the triethylamine salt of HO2C CH(2,4-dinitroaniline) CH2(2,4-dinitrophenol) - the amine salt of 0,N-bis(2,4-dinitrophenyl)-serine — and then acidifying. The compd may actually be N-vihyl-2,4-dinitroaniline, but the authors made no attempt to find out... 

Some exploratory experiments have also been carried out with some phosphate esters. Rate constants for one of these, dinitrophenyl-phosphate, are listed in Table VII. With this substrate, surprisingly, the intrinsic primary amines of the polymer seem to be acting in a turnover pathway, that is, are phosphorylated and then dephosphorylated, but this mechanism needs to be better substantiated. In any event it, it is clear that the rates in the presence of polymer are accelerated more than 103-fold with dinitrophenylphosphate. Even larger accelerations have been observed with other phosphate esters. 

Electrophilic N-aminations of imide salts have been performed with hydroxylamine-0-sulfon1c acid (HOSA),8 9,1 0-(2,4-dinitrophenyl)-hydroxylamine,11,1 and O-mesitylenesulfonylhydroxylamine (MSH),11 The use of HOSA 1s mainly restricted to aqueous reaction media.8,9 0-(2,4-... 

Dinitrophenyl)hydroxylamine, MSH, and 0-d1phenylphosphinylhydroxyl amine (DPH) can be applied in anhydrous or even non-polar solvents. 0-(2,4-... 

Alkenes can be aminated172 in the allylic position by treatment with solutions of imido selenium compounds R—N=Se=N—R.173 The reaction, which is similar to the allylic oxidation of alkenes with Se02 (see 4-4), has been performed with R = f-Bu and R = Ts. The imido sulfur compound TsN=S=NTs has also been used.174 In another reaction, compounds containing an active hydrogen can be converted to primary amines in moderate yields by treatment with 0-(2,4-dinitrophenyl)hydroxylamine.175... 

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