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Oxide chlorides from thionyl

Apart from the work toward practical lithium batteries, two new areas of theoretical electrochemistry research were initiated in this context. The first is the mechanism of passivation of highly active metals (such as lithium) in solutions involving organic solvents and strong inorganic oxidizers (such as thionyl chloride). The creation of lithium power sources has only been possible because of the specific character of lithium passivation. The second area is the thermodynamics, mechanism, and kinetics of electrochemical incorporation (intercalation and deintercalation) of various ions into matrix structures of various solid compounds. In most lithium power sources, such processes occur at the positive electrode, but in some of them they occur at the negative electrode as well. [Pg.359]

Towards metallic oxides the behaviour of thionyl chloride is similar to that of sulphur monochloride, which is perhaps hardly surprising in view of the course of its thermal decomposition. The reaction is fairly general, the oxide being converted into the corresponding anhydrous chloride. From the action of the chloride on zinc oxide (at 150° C.), cadmium oxide (at 200° C.), arsenious oxide (up to 200° C.), antimony trioxide (at room temperature), bismuth trioxide (at 150° to 200° C.), ferric oxide (at 150° C.), magnesium oxide (at 150° to 200° C.), cupric oxide (at 200° C.) and cuprous oxide (at 200° C.), it may be concluded that the main reaction, assuming a bivalent metal, M, is as follows ... [Pg.89]

Compounds (11) were also prepared in low yield by oxidation of the bishydrazine (20) by sodium hypochlorite (72JA8497), potassium ferricyanide or potassium permanganate (Scheme 3) (73CB3097). The l,4-dibenzyl-5,6-diphenyl compound (22) was prepared from 1,1,4,4-tetrabenzyltetrazene (21) by oxidative cyclization using thionyl chloride (73CL51). [Pg.534]

An improved procedure for the preparation of 4-chloropicolinyl chloride from picolinic acid and thionyl chloride has been developed (Equation 42) <20020PD777>. Phosphoryl chloride in the presence of triethylamine converts pyridine iV-oxide into 2-chloropyridine in 90% yield <2001SC2507>. [Pg.63]

When nicotinic acid is heated for 8 hours at 180° with thionyl chloride, a low yield of 5-chloronicotiriic acid is obtained.182 The orientation observed in this case suggests an electrophilic attack, perhaps on a complexed nicotinic acid chloride molecule (which would thus behave somewhat like a pyridine A-oxide). If the reaction is carried out at 150° and the reaction time lengthened to 50 hours, a 30% yield of 5,6-dichloronicotinic acid is obtained.182 Both mechanistic pathways may be involved here. Isonicotinic acid reacts with thionyl chloride at 180-220°, presumably by, way of an electrophilic attack since 3-chloro-and 3,5-dichloroisonicotinic acid are formed.182 Nicotinoyl chloride (from nicotinic acid and thionyl chloride—probably in the complexed form) gives an 87% yield of 5-bromonicotinic acid on reaction with bromine for 10 hours at 150-1700.185... [Pg.266]

The crystal and molecular structures of disulfane 1-oxides (R = 4-tolyl) and of trisulfane 2-oxides have been determined by X-ray diffraction. The latter compounds are usually obtained from thionyl chloride and thiols (RSH) in ether or in the presence of pyridine (equations 154 and... [Pg.4692]

Numerous methods have been described for the preparation of niobium(V) chloride, among them the reaction of niobium(V) oxide with thionyl chloride in a sealed system. In such a procedure some niobium(V) oxide trichloride, NbOCls, is almost always formed, and it is difficult to obtain the pentachloride completely free from this impurity, even by repeated sublimation. The simple, efficient method described here consists in allowing hydrous niobium(V) oxide to react with thionyl chloride at room temperature. Almost quantitative conversion is observed, the pentachloride dissolving in the thionyl chloride, from which it may be recovered, free of oxide trichloride, by vacuum evaporation... [Pg.88]

In addition to the obvious preparative advantages inherent in the pentachloride preparation, e.g., the low temperature of reaction and the possibility of performing the reaction without precautions against atmospheric moisture because of the protection afforded by thionyl chloride, the product is obtained free from oxide chloride. The major losses occur during the hydrous oxide precipitation and the nitric acid washings. The latter are essential to remove adsorbed ammonium ion, since, if this is not done, the reaction products will be niobium (V) chloride, in solution in thionyl chloride, and the bright yellow insoluble ammonium hexachloroniobate(V). In fact, the high purity of these two products in instances where complete removal of ammonium ion is not achieved shows clearly that the reaction of hydrous niobium (V) oxide with thionyl chloride is virtually quantitative. [Pg.91]

Treatment of 2,2,4,4-tetramethyl-3-thietanone with diiron nonacarbonyl gives the binuclear iron complex 381. 2,2-Dimethyl-3-thietanone undergoes oxidative dimerization to 382 on treatment with potassium ferricyanide. Methylene-3-thietanones such as 359 add chlorine from thionyl chloride to the carbon-carbon double bond. 2,2,4,4-tetramethyl-3-thietanone is converted to the 3-thione in 14% yield by treatment with hydrogen sulfide-hydrogen chloride. Electrochemical reduction of the thione produces radical anions. [Pg.575]

Salts of the [UC16] ion have been prepared by precipitation from thionyl chloride solutions of U(V) which were in turn prepared by the prolonged (2 weeks) refluxing of U03 with thionyl chloride3 or by the addition of solid UC15 TCAC, where TCAC = trichloro-acryloyl chloride.4 This latter extremely moisture-sensitive compound was in turn prepared by the reaction of U3 O 8 with hexachloro-propene.1,4 The method of preparation described here,2 which is applicable to the preparation of certain salts of the [UC16] ion, is based on chlorine oxidation in nitromethane solutions of the easily prepared and stored [UC16]2- salts. Some of the known salts of... [Pg.235]

Freeman and Smith (32) have prepared the anhydrous chlorides of a number of lanthanides and of thorium by dehydrating the hydrated chlorides with thionyl chloride. Although efforts to obtain anhydrous plutonium trichloride in this way were unsuccessful, it is believed that this may be a useful procedure for actinide elements such as actinium, americium, and curium that have a particularly stable (III) oxidation stage. In general, aqueous methods for preparing tetrachlorides are of little value but anhydrous trichlorides, particularly of the transuranium elements, can be obtained readily from the hydrated trichlorides by dehydration in an atmosphere of hydrogen chloride. [Pg.221]

Other important cycloelimination procedures correspond to an elimination of H2O from cyclic ketones. Thus, the a-hydrogen atoms of semicarbazones of cyclic ketones are removed by oxidative cyclization with thionyl chloride or selenium dioxide (Scheme 8-7). The 1,2,3-thiadiazoles (71) or 1,2,3-selenadiazoles (72) which result from these reactions can be cleaved in a second step to yield cyclic alkynes (Scheme 8-8) [28]. Several fragmentation conditions are known, among them thermal decomposition and base-induced cleavage. The mechanism of these reactions has been studied in detaU [29]. It has been noted that the crucial step is the cleavage of the carbon-sulfur or carbon-selenium bond, as in this step the geometrical strain is introduced into the system. Clearly, due to the weakness of the C —Se... [Pg.293]

Thiazetidines and their Derivatives.—Carboxamides with an acidic cr-hydrogen react with thionyl chloride in the presence of pyridine to give l,2-thiazetidin-3-one 1-oxides (134). ° A-Phenyl-l,2-thiazetidin-3-one 1-oxide, prepared from keten and A-sulphinylaniline, is opened by anilines to give (135). Thiofluorenone reacts with (136) to give, amongst other things, a small yield of (137) this is oxidized to its sulphonamide by MCPBA. ... [Pg.227]

Sulfonyl and Sulfinyl Chlorides from Sulfonic and Sulfinic Acids. Alkyl or arylsulfonyl chlorides are prepared by heating the acid with thionyl chloride DMF catalyzes this reaction. (+)-Camphorsulfonyl chloride is produced in 99% yield without a catalyst. Use of the salts of sulfinic acids minimizes their oxidation p-toluenesulfinyl chloride is produced in about 70% yield from sodium p-toluenesulfinate dihydrate with excess thionyl chloride. Phosphorus(V) Chloride is more commonly used for this transformation. [Pg.371]

Dicyano-l,2,3-trithiole 2-oxide (143) has been prepared from the silver salt of 2,3-dimercaptomaleonitrile (142) and thionyl chloride (66HC(2l-i)67). Similarly, the reaction of ethylene glycol (144) with thionyl chloride gave 1,3,2-dioxathiolane 2-oxide (145), the parent compound of saturated five-membered cyclic sulfites (see Chapter 4.33). [Pg.127]

A number of 1,2,3-oxathiazole 5-oxides are prepared from the reaction of thionyl chloride with various ethane derivatives having vicinal oxygen- and nitrogen-containing groups. Reaction of the 2-aminoethanol derivative (146) with SOCI2 gave (147) (see Chapter 4.34). [Pg.128]

Benzisothiazoles are best prepared by oxidative cyclization of o-aminothiobenz-amides (see Section 4.17.9.1.1), reaction of o-toluidines with thionyl chloride (see Section 4.17.9.2.1) or by sulfuration of 2,1-benzisoxazoles (see Section 4.17.10.2). 1,2-Benzisothiazoles can also be prepared from o-disubstituted benzene compounds, cyclodehydration of o-mercaptobenzaldoximes or oxidative cyclization of p-mercaptobenzylamines (see Section 4.17.9.1.1) being the most convenient. Both series of benzo compounds are readily substituted at the 5- and 7-positions by electrophilic reagents. [Pg.173]

The a -halosulfone, required for the Ramberg-Backlund reaction, can for example be prepared from a sulfide by reaction with thionyl chloride (or with N-chlorosuccinimide) to give an a-chlorosulfide, followed by oxidation to the sulfone—e.g. using m-chloroperbenzoic acid. As base for the Ramberg-Backlund reaction have been used alkoxides—e.g. potassium t-butoxide in an etheral solvent, as well as aqueous alkali hydroxide. In the latter case the use of a phase-transfer catalyst may be of advantage. ... [Pg.236]

Synthesis of the remaining half of the molecule starts with the formation of the monomethyl ether (9) from orcinol (8). The carbon atom that is to serve as the bridge is introduced as an aldehyde by formylation with zinc cyanide and hydrochloric acid (10). The phenol is then protected as the acetate. Successive oxidation and treatment with thionyl chloride affords the protected acid chloride (11). Acylation of the free phenol group in 7 by means of 11 affords the ester, 12. The ester is then rearranged by an ortho-Fries reaction (catalyzed by either titanium... [Pg.314]

Treatment of pyridyl carbinol 51 with thionyl chloride leads to the corresponding chloride (52), Treatment of that intermediate with 5-methoxy-2-mercaptobenzimidazole (53), obtained from reaction of 4-methoxy-q-phenylenediamine with potassium ethylxanthate leads to displacement of halogen and formation of the sulfide (54). Finally, oxidation with 3-chloroperbenzoic acid produces the sulfoxide omeprazole (55) fl7]. [Pg.133]

It was quite recently reported that La can be electrodeposited from chloroaluminate ionic liquids [25]. Whereas only AlLa alloys can be obtained from the pure liquid, the addition of excess LiCl and small quantities of thionyl chloride (SOCI2) to a LaCl3-sat-urated melt allows the deposition of elemental La, but the electrodissolution seems to be somewhat Idnetically hindered. This result could perhaps be interesting for coating purposes, as elemental La can normally only be deposited in high-temperature molten salts, which require much more difficult experimental or technical conditions. Furthermore, La and Ce electrodeposition would be important, as their oxides have interesting catalytic activity as, for instance, oxidation catalysts. A controlled deposition of thin metal layers followed by selective oxidation could perhaps produce cat-alytically active thin layers interesting for fuel cells or waste gas treatment. [Pg.300]

Aziridine-2-carboxylates 12 (Scheme 3.4) have also been prepared from 3-hy-droxy-a-amino esters 9 by treatment with sulfuryl chloride in place of tosyl or mesyl chloride. Treatment of 9 with thionyl chloride in the presence of triethylamine, followed by oxidation of 10 with sodium periodate and a catalytic amount of... [Pg.74]


See other pages where Oxide chlorides from thionyl is mentioned: [Pg.128]    [Pg.1210]    [Pg.580]    [Pg.128]    [Pg.128]    [Pg.92]    [Pg.89]    [Pg.373]    [Pg.172]    [Pg.353]    [Pg.304]    [Pg.598]    [Pg.20]    [Pg.309]    [Pg.172]    [Pg.277]    [Pg.274]    [Pg.219]    [Pg.201]    [Pg.1006]   


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Oxidation chloride

Oxide chlorides

Oxide chlorides, from thionyl chloride

Oxide chlorides, from thionyl chloride

Thionyl

Thionyl chloride

Thionyls

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