Diamine green

It is also easy to see that the dyestuff 2 (diamine green B) can be synthesised by joining the fragments 4 e, f, and g, in this precise order, by controlling the pH of the medium. Such an example illustrates how the molecular magnitude does not necessarily imply greater complexity in the synthetic planning (for a discussion of "molecular complexity" versus "synthetic complexity" see ref. [5]). 

Deep black V, 292 Dehydrothiotoluidine, 332 Dialkyl sulfates, 8 Diamine brown M, 286 Diamine fast red F, 286 Diamine green B, 288 Diamine pure blue, 148... 

In the preparation of diamine green B, we have seen how H acid, in mineral acid solution, couples very easily with p-nitroaniline to form a monoazo dye in which the azo group enters the position ortho to the amino group. Benzidine, however, couples appreciably less rapidly, and it is necessary to neutralize the free mineral acid that is formed. Contrary to the statements in the patent literature, it is not possible to carry out this reaction in acetic acid solution, because H acid, in the presence of sodium acetate, couples immediately in the position ortho to the hydroxyl group. These facts have given rise to many patent suits, all of which, however, have been decided in favor of the holders of the mineral acid coupling patents. 

Solution The only way to approach a problem which calls for the synthesis of a complex molecule is to go about solving the problem backwards. If Diamine Green B is broken down into component parts, the synthesis proves to be nothing more difficult than a series of successive diazo linkages. The last diazo linkage in the series involves the coupling of A with B at a pH of 5 - 7. 

And there it is, starting from nitrobenzene, alanine, phenol and H-acid a route for the synthesis of Diamine Green B has been devised. 

Dissolve about o i g. of />-phenylene diamine in about 10 ml. of water. Place 5 ml. of milk in each of two test-tubes A and B. Boil the milk in B thoroughly for 2 minutes and then cool. In each test-tube place 5 drops of the phenylenc diamine solution and then add i drop of 20 vol. hydrogen peroxide solution, and mix. A green coloration is produced in A, and then very rapidly changes to a slate-blue. No coloration is produced in B. This test therefore readily differentiates fresh from boiled milk. 

In the absence of ammonia and the concentration of polyamines being > 20 p.M the production of sediments take place. Ethylene diamine reacts with Hg(II) in the form of diimide -HNRNH- to form the insoluble complex IHgHNRNHHgl. In the presence of ammonia the production of sediments having complex composition is also possible. Given concentration of K Hgl 1-2 mM, NaOH 60-120 mM and compai able amounts of ammonia and ethylene diamine the products of reactions ai e only the soluble green-coloured complexes, bearing ammonia in the form of nitride and ethylene diamine in the form of diimide. Those complexes ai e polymers, with their absorption spectmms being different from those of the similar polymeric ammonia complexes. 

At the moment a drop of the diamine solution hits the reaction mixture, a spot becomes violet then turns to deep-green again. The addition should be slow, so that the violet color does not long persist. The yield of (Z, Z)-2,4-hexadienedinitrile decreases drastically if the addition is too fast. 

To a mixture of 1,3-dibromobenzene (4.36 g, 18.49 mmol), 1,3-phenylene diamine 111 (2.00 g, 18.49 mmol), NaO-t-Bu (3.73 g, 38.84 mmol), Pd2(dba)3 (0.339 g, 0.37 mmol), and BINAP (0.691 g, 1.11 mmol) in a heavy-walled flask equipped with a Teflon valve was added THF (15 mL) under inert atmosphere. The flask was sealed and heated to 90°C. After 24 h, die reaction mixture was cooled to room temperature and neutralized using 0.2 mol equivalents of 2.4 N HC1 in MeOH. The polymer was precipitated from hexanes, filtered, and dried under vacuum. The dried polymer was redissolved in THF, filtered through Celite, and reprecipitated. The solid was collected by filtration and dien purified by Soxlilet extraction with CH2C12 overnight. After drying under vacuum, a green-tan solid was obtain in 106% yield. GPC (NMP, polystyrene standards) Mw = 39,000 ... 

Numerous linear diamines, such as many of those in the survey mentioned above, have been evaluated as potential replacements for benzidine, an inexpensive and highly versatile intermediate that was banned in the 1970s because it posed a carcinogenic threat. Two trisazo dyes have been synthesised recently using 4,4, diaminodiphenyl thioether instead of the benzidine component of Cl Direct Black 38 (3.112 X = Y = NH2) and Cl Direct Green 1 (3.112 X = OH, Y = H). These new dyes exhibited higher substantivity and fastness to washing than the two traditional products on cellulosic fibres [119]. 

Preparation of Bindschedler s Green.1—Dimethyl-p-phenylene-diamine (7 g.) and dimethylaniline (6 g.) are dissolved in a mixture of 40 c.c. of concentrated hydrochloric acid and 40 c.c. of water. Into the solution, which is kept cool in ice and is stirred mechanically or... 

Nelson TL, O SuUivan C, Greene NT, Maynor MS, Lavigne JJ. Cross-reactive conjugated polymers anal34e-specilic aggregative response for structurally similar diamines. J Am Chem Soc 2006 128 5640-5641. 

All this can mean that, if the aq soln of unknown sample is colorless in Test 2, no ppt with,Nessler s reagent, no color with ethylene-diamine in Test 2, deep blue color with DPhA in Test 3 and green a>lor with thymol soln in Test 4, it could be NG... 

The acid chloride, [Co en2Cl2]Cl.HC1.2H20, is formed by mixing a solution of cobaltous chloride with an aqueous solution of ethylene-diamine monohydrate and oxidising the mixture with air. Concentrated hydrochloric acid is then added and the whole heated on a water-bath for one hour. The liquid is allowed to stand, when crystals separate, and are filtered and washed with concentrated hydrochloric acid.2 The salt crystallises in dark green rhombic plates. It is soluble in water, though less soluble than the normal salt, and on heating to 100° C. is transformed into the normal salt. 

Selected nickel(II) complexes with C-substituted diamines are listed in Table 41. In solution the square planar coordination is favoured,700 while both square planar and six-coordinate complexes have been isolated in the solid state. Complexes with l,2-diphenyl-l,2-diaminoethane (stilbendiamine, stien) and l-phenyl-l,2-diaminoethane have been widely studied.701-706 Using CI2CHCO2 as counterion, two complexes have been obtained with the former ligand, one blue, monoclinic, P2Jc ( Ueif = 3.16BM), the other yellow-green, triclinic,... 

Diamine, benzo. dianil, Columbia, chlorazol, naphthamine, etc., greens... 

The enzymes commonly used are pure and have a high turnover number (48). They include horseradish peroxidase (with o-phenylene diamine as substrate which yields a yellow colored product, 2,2 azino-(3ethyl)-benzo-sulphonic acid gives green colored product, or tetramethyl benzidine gives a blue product) and alkaline phosphatase (with p-nitro phenyl phosphate as substrate to give a yellow /orange colored product). 

The trisazo dyes include in particular blue, green, and black grades. Diamines used are 4,4 -diaminobenzanilide (DABA) and 4,4 -diaminodiphenylaminc-2-sul-fonic acid (DADPS). The most important synthetic principle in this range is the type K i<— Di- K2<— D2. The sequence of the three couplings depends on the nature of the components. 

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