Anhydrides tests for

Chemical Tests. Benzoin contains an aromatic ring. Confirm this fact by performing the ignition test (Chapter 9). To confirm the presence of the alcohol and ketone functions in benzoin carry out the chromic anhydride test for the —OH group and the 2,4-dinitrophenylhydrazine test for the C=0 group. Isolate the solid 2,4-dinitrophenylhydrazone derivative and compare its melting point to the literature value. 

The fluorescein test for succinic acid (p. 349) and the phthalein and fluorescein tests for phthalic acid (p. 351) are obviously given also by succinic anhydride and phthalic anhydride, as these tests depend upon the initial formation of the anhy dride in each case. 

It is convenient to consider the indiflferent or neutral oxygen derivatives of the hydrocarbons—(a) aldehydes and kelones, (b) esters and anhydrides, (c) alcohols and ethers—together. All of these, with the exception of the water-soluble members of low molecular weight, are soluble only in concentrated sulphuric acid, i.e., fall into Solubility Group V. The above classes of compounds must be tested for in the order in which they are listed, otherwise erroneous conclusions may be drawn from the reactions for functional groups about to be described. 

Test for cholesterol about 5 mg. of material is dissolved in 2 cc. of carbon tetrachloride i cc. of acetic anhydride and 3-4 drops of concentrated sulfuric acid are added. Cholesterol gives a succession of color changes. 

Another patent apphcation (28) describes the use of zeolite/TUD-1 with optionally a metal function for a variety of reactions. In an example, as-synthesized MCM-22 / TUD-1 was tested for acylation of 2-methoxynaphthalene with acetic anhydride to 2-acetyl-6-methoxynaphthalene at 240°C. After reaction for six hours, conversion of 2-methoxynaphthalene reached 56% with 100% selectivity to 2-acetyl-6-methoxynaphthalene. Other zeolite catalysts were similarly tested, but none were nearly as effective. 

One of the most systematic investigations into the use of organic chemical microscopy was made by Dunbar and his associates, who used a series of specific reagents to develop specific tests for various functional groups. Methods were developed for amines [24,25], carboxylic acids, anhydrides, and acid chlorides [26,27], aldehydes and ketones [28], hydroxy compounds [29], amino acids [30], and cations [31]. 

Both compounds were tested for their catalytic activity in asymmetric aziridination using p-toluenesullbnic anhydride (TS2O) to activate the nitridomanganese complex. As shown in Scheme 4-60, the aziridination generally gave poor results, while addition of pyridine A-oxide improved both the yield and the enantiomeric excess of the products. 

Anhydrides of ketoses have not been tested for polymerizability, but two monomeric anhydrides of D-fructose have been reported, namely, 2,3-anhydro-l,4,6-tri-0-nitro-D-fructofuranose71 and 2,6-anhy-dro-l-O-methyl-D-fructofuranose.72 The structures of both suggest that they have sufficient strain to be of interest. The first is the product of a... 

Fleet and co-workers (75a) synthesized various tetrazoles from manno- and rhamnopyranoses, as well as furanoses, based on the intramolecular 1,3-dipolar cycloadditions of azides with nitriles (Scheme 9.75). All of these tetrazoles were tested for their inhibitory activities toward both glycosidases and other sugarprocessing enzymes. D-Mannopyranotetrazole (397) was prepared from L-gluono-lactone (393). Azide 394 on ring opening with ammonia followed by dehydration with trifluoroacetic anhydride gave the azido nitrile 395. Intramolecular 1,3-dipolar cycloaddition of 395 in refluxing toluene followed by deprotection produced the D-mannopyranotetrazole 397 in 86% overall yield. 

Reaction of 164 with acetic anhydride, reaction of isatin with L-pipecolic acid, or reaction of pyrrolidine with isatin in acetic anhydride gives a substance known as isatin blue. Proline and isatin give the same product and the blue color is the basis of a color test for such compounds.463-468 The structure 166 has been proposed for isatin blue,461 and other related compounds have also been prepared.461... 

Analysis always necessitates determinations of the sugar (saccharose) and of the soluble salts, since from these is calculated the yield (rendement) on refining. Determinations may also be made of the invert sugar, water, non-sugar and, in some cases, raffinose, total ash and alkalinity sometimes sulphurous anhydride is tested for, but the colour is seldom measured. 

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