Amine picrate

Primary and Secondary Amines. Picrates (pp. 374, 376), Acetyl derivatives (pp. 373, 376), Benzoyl derivatives (pp. 374, 376), Toluene-p-sulphonyl and benzene-sulphonyl derivatives (pp. 374, 376), Phenylurea derivatives (pp. 374, 377)-... 

Tertiary Amines. Picrates (p. 378), Methiodides (p. 377), />-Nitroso-deriva-tives (p. 378). 

Bis(/3 nitroxyethyl) amine Picrate. See under Di(ethylol)-amine... 

Mansit. An expl mixt consisting of AN 72, Amin Picrate 23 and petroleum asphalt 5% Ref Blinov, Vol 2 (1948)... 

In over half of a series of 33 samples of arterial blood of hypertensives, the amine picrates measured in terms of isoamylamine were higher than in twelve of fifteen normal ones, and in nine cases were more than 10 mg. per liter. The normal range was 0 to 7.0 mg., only three being greater than 3 mg. In a second series, the results, expressed in terms of units of color, showed high values in two of twelve normal subjects, seven of fourteen patients with neurogenic hypertension, and eleven of thirteen with renal hypertension. The color-concentration curves obtained from picrates of various amines, however, differed in their slopes therefore the amount of color found was no true indication of the actual concentration of any one amine. 

Formation of an Amine Picrate from Picric Acid and Triethylamine... 

This procedure was tested using both amine picrates and amine oxide picrates. The milliequivalent weights of the picrates determined were within 1% of the theoretical value. 

Picric acid forms ionic salts with amines, picrates, which are solids of characteristic melting point even though the parent acids are liquids for example, the picrates of m-anisidine, N,N-diethylaniline, and N-methylaniline melt at 169, 142, and 144°. 

Eksborg and Schill1 separated a series of alkylamines on a cellulose column loaded with a 0.06 M aqueous picrate solution, of pH 11.2, using as mobile phase chloroform - 1-pentanol (19 1). Addition of the alcohol to the mobile phase was necessary to reduce tailing. Celite and porous silica gel were found to be less suitable as solid support for aqueous picrate solutions. At the low pH necessary to ionize tertiary, secondary and primary amines, picrate... 

Amines, RNH2, react with picric acid to form amine picrates, which absorb strongly at 359 nm (e = 1.25 X 10 ). An unknown amine (0.1155 g) is dissolved in water and diluted to 100 mL. A 1-mL aliquot of this is diluted to 250 mL for measurement. If this final solution exhibits an absorbance of 0.454 at 359 nm using a 1.00-cm cell, what is the formula weight of the amine What is a probable formula ... 

Chloroaniline in a sample is determined as the amine picrate as described in Example 16.3. A 0.0265-g sample is reacted with picric acid and diluted to 1 L. The solution exhibits an absorbance of 0.368 in a 1-cm cell. What is the percentage chloroaniline in the sample ... 

Amines (weak base) form salts with picric acid (trinitrophenol), and all amine picrates exhibit an absorption maximum at 359 nm with a molar absorptivity of 1.25 X 10 . A 0.200-g sample of aniline, C6H5NH2, is dissolved in 500 mL water. A 25.0-mL aliquot is reacted with picric acid in a 250-mL volumetric flask and diluted to volume. A 10.0-mL aliquot of this is diluted to 100 mL and the absorbance read at,35, nm in a 1-cm cell. If the absorbance is 0.425, what is the percent purity of the aniline -... 

Activity Relationship) or linear-solvation-energy approaches are based on a direct account of both these factors through special parameters (e.g., [61—66]). However, as is exemplified by the amine picrates—octanol data of Table 1, in the case of pure solvent the selectivity is much less prominent. Actually, as log K -x (host-amine-picrate) = log Kass (host-amine-picrate) + log Kdisrr (amine-picrate, pure solvent), the discriminating abilities of host and solvent are favorably additive. 

An interesting question was what length of polyether chain is optimal for binding ammonium ions. As an answer. Fig. 3 shows distribution ratios of amine picrates versus the number of the host s oxygens (= k + 3 data of Ref. 113). We may conclude that the larger the podand, the better the extraction however, three or four oxyethylene units is a sufficient length. 

Figure 3 Extraction of amine picrates into chloroform with phosphoryl podands. Distribution ratios versus the size of podand (Chose = 0.01 M, C u . = 0.0003 M, Cpitraic = 0.0001 M data of Ref. 113.)...

Primary and Secondary Amines Acetamides 658 Primary and Secondary Amines Benzamides 659 Primary, Secondary, and Tertiary Amines Picrates 659 Acid Chlorides and Anhydrides 660 Amides 660... 

Molecular weights of amine picrates, sugars, and many aldehyde and ketone compounds have been determined by this method. The method has an accuracy of 2%. Molecular weights of only small molecules may be determined by this method. 

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