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Anhydrid, acetic carbonic

Ammonium nitrate and other ammonium salts Any oxidizable substance, such as ethanol, methanol, glacial acetic acid, acetic anhydride, benzaldehyde, carbon disulphide, glycerol, ethylene glycol, ethyl acetate, methyl acetate or furfural Chlorates, perchlorates, permanganates... [Pg.233]

Acetic anhydride Potassium carbonate Sodium hydroxide... [Pg.952]

Indolylaminomethylenemalonates (681) were regioselectively cyclized on the action of acetic anhydride or trifluoroacetic anhydride in carbon tetrachloride at 10-20°C for 3 hr, to give 8-carbolines (682) in 22-75% yields (85ZOR432). [Pg.158]

Synthetic routes to a-nitroalkenes have been discussed in previous sections. General routes include (1) treating /3-nitroacetates with alkali metal acetates, carbonates or bicarbonates, (2) elimination of water from /3-nitroalcohols via heating with phthalic anhydride or in the presence of a base," ° and (3) degradation of the Mannich products derived from a primary nitroalkane, formaldehyde, and a secondary amine. ... [Pg.38]

Oxidation of 2,4-dimethyl- 2 -pentane gave the desired epoxide in high yield- (Eq. 109), and no other products were isolated,7 7 The reaction was conducted at 0° in a mixture of acetic anhydride and carbon disulfide. Under these conditions 2-methyl-2-butene. in which a... [Pg.367]

Previously, the reaction of 3,4,6-tri-0-acetyl-l,5-anhydro-2-deoxy-D-arabino-hex-l-enitol (D-glucal triacetate) (20) with lead thiocyanate in a mixture of acetic acid, acetic anhydride, and carbon tetrachloride had been reported by Igarashi and Honma.37 They observed formation of isothiocyanate 21 as the main product, accompanied by a mixture of four isomeric thiocyanates. [Pg.96]

The body is insoluble in water, sparingly soluble in cold methyl alcohol, ether, acetone, chloroform, acetic acid, acetic anhydride or carbon tetrachloride, but more soluble on heating it readily sublimes, and has a faint agreeable odour. When boiled with iodine in chloroform solution it forms a tetra-iodide,... [Pg.121]

According to both the NFPA Guide and Bretherick (Refs 5 13), sulfuric acid causes explosions and/or fires when in intimate contact with a large number (over 70) of materials including acetic anhydride, acet and nitric acid, acrolein, alcohols, alcohols and hydrogen peroxide, anun hydroxide, aniline, bromine and metals, carbides, chlorates, cyclopentadiene, ethylene glycol, various hydrocarbons, hydrochloric acid, iron, mercuric nitride, powdered metals, perchlorates, picrates, pyridine, Na carbonate, steel, sucrose, vinyl acetate, and w. Illustrative... [Pg.475]

Cyanobutanal Succinic anhydride Acetic anhydride Dicyclohexylcarbodiimide Palladium on carbon... [Pg.1203]

Another process to make acetic anhydride involves carbon monoxide insertion into methyl acetate (Fig. 1). [Pg.14]

The 1-hydroxyl group of XXV has a sufficiently strong attachment to the carbon atom to prevent the ready prior transformation to the open form before the hydrogenation.1 This anhydride acetate XXXII is a thick distillable oil that no longer exhibits an aldehyde reaction. After deacetylation, a crystalline benzylidene derivative1 can be prepared by treatment with benzaldehyde and zinc chloride. The action of phosphorus pentachloride on a thionyl ester of the deacetylated substance leads to an oily 4,6-dichloro derivative (XXXIII).1 ... [Pg.224]

Examples of the use of chromium(VI) reagents to effect the allylic oxidation of alkenes to give a,3-unsaturated carbonyl compounds are very common in the literature. The reaction was first reported by Treibs and Schmidt for the allylic oxidations of a-pinene to verbenone and verbenol, of dipentene to carvone and caiveol, and of cyclohexene to cyclohexenol and cyclohexenone, using a solution of chromium trioxide in a mixture of acetic anhydride and carbon tetrachloride. However, yields were low and no synthetic use of this observation was made. [Pg.99]

Burton and Praill were the first to prqjare this ecies both by the interaction of perchloric acid with acetic anhydride and the metathetic reaction of sflver perchlorate with acetyl chloride , in a comprehensive study of acylation reactions. They did not attempt a characterisation of the compound and assumed that in acid solutions it existed in a fully ionised form. A few years later, Jander and Surawski followed the formation of acetyl perchlorate in acetic anhydride by measuring the electrical conductivity changes which took place when acetyl bromide was added to silver perchlorate or vice versa. In both titrations an inflection point was observed for a mixture of equimolar quantities of the two reactants indicating the formation of acetyl perchlorate. Moreover, it was clearly drown that this compound was at least partly ionised since its conductivity was higher than that of acetyl bromide. Avedikian and Commeyras characterised acetyl perchlorate by infrared and Raman spectroscopy both in acetic anhydride and carbon tetrachloride. They concluded that some ionisation was present but could not assess its extent. Molecular acetyl perchlorate was also detected. As far as we are aware, no other study of the structure and extent of dissociation of acetyl perchlorate in solution has been conducted. [Pg.212]

The reactions shown in this section illustrate the versatility of Af-substituted pyridines in the synthesis of condensed heterocycles containing pyrrole. Some of the cyclizations proceed without the need for externally applied heat [2419, 2422,2830,2980a], and for most of the cyclizations, the conditions are relatively mild. The preformed ylide is used in some of the reactions while in others, it is generated in situ. It is even possible to react a 2-methylpyridine with an Af-alkyl-ating agent, such as bromoacetone, and then cyclize the intermediate iV-alkyl derivative by heating with sodium acetate-acetic anhydride or carbonate without isolating either the intermediate. /V-alkylpyridine or the ylide [2157, 2295, 2393, 3512]. [Pg.671]

It has been reported that microwave irradiation shortens the reaction time of the Perkin reaction by 60-fold over classical heating. Cesium salts (acetate, carbonate, fluoride) with a small amount of pyridine were found to be the best catalysts.12 Thus, p-hydroxybenzaldehyde (45) reacted with acetic anhydride using cesium acetate as a catalyst to provide the a, p-unsaturated acid 46 in 85% yield. [Pg.367]


See other pages where Anhydrid, acetic carbonic is mentioned: [Pg.62]    [Pg.101]    [Pg.169]    [Pg.391]    [Pg.762]    [Pg.98]    [Pg.148]    [Pg.101]    [Pg.1080]    [Pg.1081]    [Pg.328]    [Pg.335]    [Pg.324]    [Pg.216]    [Pg.391]    [Pg.407]    [Pg.80]    [Pg.1390]    [Pg.117]    [Pg.101]    [Pg.328]    [Pg.335]    [Pg.873]    [Pg.194]    [Pg.375]    [Pg.447]   
See also in sourсe #XX -- [ Pg.318 ]




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Carbon acetates

Carbonic Anhydride

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