Amine acetate

With the aid of a small pipette or a fine-bore dropping-tube (Fig. 30, p. 60), add about 4 drops of the filtered enzyme solution to the amine acetate solution. Using another dropping-tube add i drop of 20 volume hydrogen peroxide solution and shake well. Note the colour change which takes place. 

The fine mica fraction is deslimed over 0.875—0.147-mm (80—100-mesh) Trommel screens or hydrocylcones, or is separated with hydrosi2ers. The deslimed pulp (<0.589 mm (—28 mesh)) of mica, feldspar, and quart2 is then fed to a froth flotation circuit where these materials are separated from each other either by floating in an acid circuit with rosin amine and sulfuric acid (2.5—4.0 pH), or an alkaline circuit (7.5—9.0 pH) with tall oil amine, goulac, rosin amine acetate, and caustic soda (see Eig. 2). 

Eatty amines are insoluble in water, but soluble in organic solvents to varying degrees (26—29). Water, however, is soluble in the amines, and hydrates are formed. SolubiHty in organic solvents is dependent on solvent polarity and temperature. The solubiHties of primary amine acetates and... 

Amine salts, especially acetate salts prepared by neutralization of a fatty amine with acetic acid, are useflil as flotation agents (collectors), corrosion inhibitors, and lubricants (3,8). Amine acetates are commercially available from a number of suppHers Akzo Chemicals Inc. (Armac) (73) Henkel Corporation (formerly General Mills) (Alamac) (74) Jetco Chemicals Inc. (The Procter Gamble Company) (fet Amine) (75) Sherex (Adogen) (76) and Tom ah Products (Exxon Chemical Company) (Tomah) (77). 

Alkylthio, arylthio, and thioxo. The thioxo group in pyrimidine-2,4-dithione can be displaced by amines, ammonia, and amine acetates, and this amination is specific for the 4-position in pyrimidines and quinazolines. 2-Substitution fails even when a 5-substituent (cf. 134) sterically prevents reaction of a secondary amine at the 4-position. Acid hydrolysis of pyrimidine-2,4-dithione is selective at the 4-position. 2-Amination of 2-thiobarbituric acid and its /S-methyl derivative has been reported. Under more basic conditions, anionization of thioxo compounds decreases the reactivity 2-thiouracil is less reactive toward hot alkali than is the iS-methyl analog. Hydrazine has been reported to replace (95°, 6 hr, 65% 3deld) the 2-thioxo group in 5-hexyl-6-methyl-2-thiouracil. Ortho and para mercapto- or thio- azines are actually in the thione form. ... 

Amine acetates [R-NH2-CH3COOH]. Examples include hydrogenated tallowalkylamine acetate and octadecylamine actetate. 

C 1 sH 1 7NO1, Amine, acetals Alkaloid (72) (27) T338 W459... 

Allyl Halides, Sulfides, Amines, Acetals and Dithioketals. 132... 

Figure 23.9 Effect of amine acetate on the flotation of individual minerals.

The Ta/Nb flotation was accomplished using collector RS702. This collector is composed of amine acetate, phosphoric acid esters and hydroxamate. Collector RS702 is a powerful collector, capable of floating a variety of niobium minerals that are contained in the flotation feed. Metallurgical results obtained from a continuous locked-cycle test are shown in Table 23.14. 

A number of different chromium collectors were also examined, including R84, which is a sulphonate collector as the primary collector, and amine acetate as the secondary collector was found to be effective for chromium flotation. The most critical parameter for selective chromium flotation was the pH. Selective chromium flotation occurs at a very narrow pH region, 1-2.5. Figure 25.12 shows the effect of pH on chromium flotation. 

Ail equimolar mixture of an aldehyde 1, ail amine acetate, and a malonic acid derivative 3 (without solvent) was irradiated in an open glass vessel in a micro-wave oven (Funai M0785VT, 170 W) for several minutes (until the release of CO2 was complete). The reaction was monitored by TLC. The reaction products were separated by column chromatography on silica gel with a benzene-ethyl acetate eluent (2 1). Note that an increase in the microwave power up to 350 W resulted in a decrease in the yield of the target amino ester. 

Figure 18.15 Resolution of ketoximes to amine acetates via EMCR (Kim, 2002).

The EMCR has been extended from obtaining enantiomerically pure alcohols to obtaining such amines. Prochiral ketoximes were transformed to optically active amine acetates in a coupled CALB/palladium catalysis in the presence of an acyl donor at 1 atm hydrogen (Figure 18.15) (Choi, 2001). 

Phthalic anhydride Ethyldiisopropyl amine Acetic acid Thiourea n-Propanal Hydrobromic acid... 

Mechanistically, the Beirut reaction is a heterocycle expansion-process where the nucleophile attack conducts, after atomic rearrangements, to a new diazine system. In general, a further elimination—i.e., of H2O, amines, acetate—aromatizes the new heterocycle. 

In all the retrosynthetic analyses you ve seen so far there is a heteroatom (N or O) joining the rest of the molecule together, and in each case we made the disconnection next to that N or O, This guideline works for esters, amides, ethers, amines, acetals, sulfides, and so on, because these compounds are often made by a substitution reaction,... 

In terms of functional group compatibility, ethers, alcohols, tertiary amines, acetals, esters, amides and heterocycles are compatible with the Pauson-Khand reaction. In the intramolecular version, relatively few carbon skeletons undergo the cyclization. Most intramolecular PKRs use systems derived from hept-l-en-6-yne (6) or propargyl allyl ethers (7) or amines (8). Other interesting and more recent substrates are enynes connected through aromatic rings like 9-11, which have allowed us and other groups to obtain aromatic polycycles (Fig. 1) [28-31]. 

SYNS 1,4 -DIMETHYL-5H-PYRIDO(4,3-b)INDOL-3-AMINE ACETATE l,4-DIMETHYL-5H-PYRIDO(4,3-b)INDOL-3-AMINE MONOACETATE TRP-P-1 (ACETATE)... 

DIMETHYL-5H-PYRIDO(4,3-b)INDOL-3-AMINE ACETATE see AJR500... 

The best correlation equation for racemic a-amino acids separated on a-cyclodextrin column using 1% triethyl-amine acetate (pH=5.1) as a mobile phase is ... 

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