I Oxide In

Ochiai and Okamoto showed that nitration of quinoline i-oxide in sulphuric acid at o °C gave 5- and 8-nitroquinoline i-oxides with a trace of the 4-isomer, but that at 60-100 °C 4-nitration became overwhelmingly dominant. The orientation depends not only upon temperature but also upon acidity, and kinetic studies (table 8.4 table 10.3) show that two processes are occurring the nitration of the free base (vil, R = O at C(4), favoured by low acidities and high temperatures, and the nitration of the cation (vil, R = OH), favoured by high acidities and low temperatures. ... 

The diazonio group can also be replaced by —OH to yield a phenol and by —H to yield an arene. A phenol is prepared by reaction of the arenediazonium salt with copper(I) oxide in an aqueous solution of copper(ll) nitrate, a reaction that is especially useful because few other general methods exist for introducing an -OH group onto an aromatic ring. 

J, Schatz, Thiophenes, Thiophene 1,1-Dioxides, and Thiophene I-Oxides, in Seience of Synthesis, vol, 9, ed. G. Maas. Thieme, Stuttgart. 2001, chap. 9.10,... 

In manchen Fallen lassen sich Reaktionen der hier beschriebenen Art nicht unter den stark sauren Bedingungen der Hofmann-Loffler-Reaktion durchfuhren. Man kann dann die (z. B. intramolekulare) N-Alkylierung mittels Silber(I)-oxid in Acetonitril/Wasser (9 1) bewerkstelligen6. Beispiele fiir diese Arbeitsweise sind die intramolekularen Dehydrochlo-rierungen von 1-Chlor-azocan zu Hexahydropyrrolizin (72%) und von 1-Chlor-azonan zu Octahydroindolizin (57%)6 ... 

Chlorine, determination of, in chlorine(I) oxide in carbon tetrachloride and hypochlorous acid solutions, 5 162, 164 Chlorine(I) compounds, 5 156 Chlorine(I) oxide, 5 156 in carbon tetrachloride solution, 5 158, 159 analysis of, 5 162 Chlorine(IV) oxide, 4 152 admixed with inert gas and chlorine, 4 153... 

Sodium chlorate, formation of, in preparation of chlorine (I) oxide in carbon tetrachloride solution, 5 159n. 

Many sensitive substrates would not survive the ravages of sodium or potassium hydride and the attendant alkoxide anions. There are gentler methods, An alcohol can be protected with benzyl bromide in the presence of silver I) oxide in... 

The reactions between i-dinitrobenzene or 1,3,5-trinitrobenzene, aryl halides, and copper(I) oxide in quinoline 17-19, 21) provide a simple synthesis of nitrobiphenyls uncontaminated by symmetrical biphenyls. These couplings may be related to the Ullmann reaction, the decarboxylative coupling of benzoic acids with aryl halides, and the preparation of ethers from phenols 165). Although no intermediates... 

Bacon and Pande have presented their views of the possible reactions between aryl halides and copper(I) oxide in pyridine in a scheme (Fig. 8)... 

Benzo-1,2-quinone (11) is prepared by the oxidation of 1,2-dihydrox-yhenzene (catechol) with silver(I) oxide in diethyl ether. This compound is not very stable and is also an oxidizing agent. 

Aldehydes are oxidized selectively in the presence of other functional groups using silver(I) oxide in aqueous anunonium hydroxide (Ag20 in NH4OH). This is called Tollens reagent. 

Thiabenzene I-oxide. The reaction of 1,3-disubstituted 2-propynones such as l,3-diphenyl-2-propyn-I-onc (1) with dimethyloxosulfonium methylide in DMSO at 16.5° gives l-mcthyl-3,5-disubstituted thiabenzene I-oxides in the case of (I) the product is l-methyl-3,5-diphenylthiabenzene l-oxide (3), obtained in 76% yield. If the reaction is carried out in THF-DMSO at - 8°, the intermediate (2) can be isolilted it probably arises by Michael addition of the reagent to (I). 

Dissolve the copper(I) oxide in the third and fourth tubes in a 25% ammonia solution. Rapidly close one of them tightly with a stopper, leave the other one open, and vigorously shake both tubes. Does the colour of the solution change Explain what you observe. Write the equations of the reactions. 

The crystalline air-sensitive complex (CgHe)[Cu(0S02CFg)]2 has been isolated from the reaction of trifluoromethanesulfonicanhydride with Cu(I) oxide in benzene (38J). The complex was stable to 100°C when heated in a sealed evacuated tube, the benzene being released quantitatively only above 120°C. The structure has been determined and consists of infinite chains of Cu(S03CF3) units cross-linked in sheets by the benzene molecules (94). The benzene-Cu(I) coordination is shown in (XLI). The structure was not sufficiently well-resolved to observe... 

Saponification of the diester followed by acidification gives the corresponding malonic acid which is then decarboxylated. The decarboxylation step may require high temperatures (150-250 °C). Treatment of malonic acids with a catalytic amount of Cu(I) oxide in acetonitrile is reported to accelerate the decarboxylation step and affords the monoacid products in good yield under milder conditions. ... 

Acidic conditions for hydroxy deprotection can be avoided if benzyl-type ethers ate used as the blocking functions. They can be prepared from the alcohols by alkylation with benzyl halide/sodium hydride in DMSO or benzyl halide/silver(I) oxide in DMF (the silver salt does not cause acyl migration as a side... 

Dispositional kinetics and metabolism of (S)-nicotine N-I -oxide in rabbits. DrugMetab Dispos 19 667, 1991. 

A solution of chlorine (I) oxide in carbon tetrachloride is easier to obtain and safer to handle than the pure compound. The first3 of the two procedures given is better for laboratory syntheses the second resembles an industrial method of producing chlorine(I) oxide.4 On a large scale, the second is the more economical and avoids the use of toxic mercury compounds. As a laboratory procedure, it has the disadvantages of being difficult to control and of converting only about half of the chlorine dissolved in the carbon tetrachloride into chlorine(I) oxide. 

Maximum concentrations of hypochlorous acid are obtained by treating pure liquid chlorine(I) oxide with water at 0°. Lower concentrations result from use of the gaseous oxide under reduced pressure or from use of solutions of the oxide in carbon tetrachloride. The last procedure is convenient for acid concentrations up to 5 M. The reaction is nearly quantitative, the equilibrium concentrations of hypochlorous acid and chlorine (I) oxide in the two phases at 0° being calculated from the data of... 

The concentration of chlorine(I) oxide-in carbon tetrachloride and the volume of the solution are first determined. Then the quantity of water that must be added to give a solution of hypochlorous acid of the desired concentration is calculated from the expression... 

A. Chlorine and Chlorine (I) Oxide in Carbon Tetrachloride.8 This procedure is based upon the fact that liberation of iodine by the reaction between either chlorine (I) oxide or hypochlorous acid and a solution of potassium iodide is accompanied by the consumption of hydrogen ion in the proportions shown by the equations... 

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