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Chlorides, acid complex

CH2CI-CO-CH3. Colourless lachrymatory liquid b.p. 119°C. Manufactured by treating propanone with bleaching powder or chlorine. It is used as a tear gas and is usually mixed with the more potent bromoacetone. chloro acids Complex chloroanions are formed by most elements of the periodic table by solution of oxides or chlorides in concentrated hydrochloric acid. Potassium salts are precipitated from solution when potassium chloride is added to a solution of the chloro acid, the free acids are generally unstable. [Pg.93]

An alternative polymerization process utilizes a slurry of calcium chloride in NMP as the polymerization medium. The solubiHty of calcium chloride is only 6% at 20°C however, the salt continues to dissolve as conversion of monomers to polymer proceeds and calcium chloride/polyamide complexes are formed. Polymer molecular weight is further increased by the addition of /V, /V- dim ethyl a n i1 in e as an acid acceptor. This solvent system produces fiber-forming polymer of molecular weights comparable to that formed in HMPA/NMP. [Pg.65]

Because of the cost of pyridine the phosgenation process may be carried out with a mixture of pyridine and a non-hydrohalide-accepting solvent for the polymer and the growing complexes. Suitable solvents include methylene dichloride, tetrachlorethane and chloroform. Although unsubstituted aromatic hydrocarbons may dissolve the solvent they are not effective solvents for the acid chloride-pyridine complexes. [Pg.561]

Titanium tetrachloride and tin tetrachloride can form complexes that are related in character to both those formed by metal ions and those formed by neutral Lewis acids. Complexation can occur with an increase in the coordination number at the Lewis acid or with displacement of a chloride from the metal coordination sphere. [Pg.235]

Bromination is catalyzed by Lewis acids, and a study of the kinetics of bromination of benzene and toluene in the presence of aluminum chloride has been reported. Toluene is found to be about 35 times more reactive than benzene under these conditions. The catalyzed reaction thus shows a good deal less substrate selectivity than the uncatalyzed reaction, as would be expected on the basis of the greater reactivity of the aluminum chloride-bromine complex. [Pg.578]

The formation of acyl halide-Lewis acid complexes have been observed by several methods. For example, both 1 1 and 1 2 complexes of acetyl chloride, with AICI3 can be observed by NMR spectroscopy. The existence of acylium ions has been demonstrated by X-ray diffraction studies on crystalline salts. For example, crystal structure determinations have been reported for /i-methylphenylacylium and acetylium ions as SbFg salts. There is also a good deal of evidence from NMR measurements which demonstrates that acylium ions can exist in nonnucleophilic solvents. " The positive charge on acylium ions is delocalized onto the oxygen atom. This delocalization is demonstrated in particular by the short O—C bond lengths in acylium ions, which imply a major contribution from the structure having a triple bond ... [Pg.584]

With trifluoroacetic acid, it was reported that very little exchange took place at 50 °C, even after a period of days, which is surprising in view of the fact that there was spectral evidence of complex formation between the acid and stannic chloride. The complex was assumed to be unreactive towards exchange and at the same time to compete in its formation with the formation of a complex between stannic chloride and the toluene solvent. In the absence of stannic chloride, about 20 % exchange would take place in seven days (see Table 159, p. 244). [Pg.240]

This hydrogen chloride-perchloric acid complex spontaneously dissociates with explosive violence. [Pg.1420]

It is more convenient to start with the triflate ion [Rh(NH3)5(CF3S03)]2+ since triflate is a much better leaving group than chloride and is immediately replaced by liquid ammonia [87]. A third route involves acid hydrolysis of the cyanate complex [Rh(NH3)5(NCO)]2+, which proceeds quantitatively (probably via a carbamic acid complex). Vibrational studies on Rh(NH3) + assign stretching vibrations as i(Alg) at 514cm-1, i/2(Eg) at 483 cm-1 and i/j(T,u) at 472 cm-1 [88],... [Pg.132]

Ashby and Craig72 reported that MeSn3+ and small amounts of Me2Sn2+ are also produced when a baker s yeast (Saccharomyces cerevisiae) is incubated with tin(II) compounds including tin(II) oxalate, tin(II) sulfide and various tin amino acid complexes. Tin(II) chloride and tin(II) amino acid complexes were methylated by methyl-cobalamin, under conditions of chloride ion concentrations and pH relevant to the natural environment73. The main identified product of all reactions was monomethyltin. [Pg.890]

The controlled occurrence of two electrophilic aromatic substitution reactions at a single phosphorus center using phosphorus trichloride has been accomplished using aluminum chloride as the catalyst, but with tris(2-chloroethyl) phosphite as the agent for the decomposition of the adduct-Lewis acid complex (Figure 6.13).60... [Pg.173]

Vitamin B12 catalyzed also the dechlorination of tetrachloroethene (PCE) to tri-chloroethene (TCE) and 1,2-dichloroethene (DCE) in the presence of dithiothreitol or Ti(III) citrate [137-141], but zero-valent metals have also been used as bulk electron donors [142, 143]. With vitamin B12, carbon mass recoveries were 81-84% for PCE reduction and 89% for TCE reduction cis-l,2-DCE, ethene, and ethyne were the main products [138, 139]. Using Ni(II) humic acid complexes, TCE reduction was more rapid, leading to ethane and ethene as the primary products [144, 145]. Angst, Schwarzenbach and colleagues [140, 141] have shown that the corrinoid-catalyzed dechlorinations of the DCE isomers and vinyl chloride (VC) to ethene and ethyne were pH-dependent, and showed the reactivity order 1,1-DCE>VC> trans-DCE>cis-DCE. Similar results have been obtained by Lesage and colleagues [146]. Dror and Schlautmann [147, 148] have demonstrated the importance of specific core metals and their solubility for the reactivity of a porphyrin complex. [Pg.530]

With propene, n-butene, and n-pentene, the alkanes formed are propane, n-butane, and n-pentane (plus isopentane), respectively. The production of considerable amounts of light -alkanes is a disadvantage of this reaction route. Furthermore, the yield of the desired alkylate is reduced relative to isobutane and alkene consumption (8). For example, propene alkylation with HF can give more than 15 vol% yield of propane (21). Aluminum chloride-ether complexes also catalyze self-alkylation. However, when acidity is moderated with metal chlorides, the self-alkylation activity is drastically reduced. Intuitively, the formation of isobutylene via proton transfer from an isobutyl cation should be more pronounced at a weaker acidity, but the opposite has been found (92). Other properties besides acidity may contribute to the self-alkylation activity. Earlier publications concerned with zeolites claimed this mechanism to be a source of hydrogen for saturating cracking products or dimerization products (69,93). However, as shown in reaction (10), only the feed alkene will be saturated, and dehydrogenation does not take place. [Pg.272]

The Lewis acid catalyzed reaction of furan (169) with ketovinylphosphonate 170 produced a mixture of adducts, both of which slowly underwent retro Diels-Alder reactions at room temperature121. When diethylaluminum chloride was used as the catalyst, the endo selectivity (with respect to the keto functionality) was enhanced from 171/172 = 58/42 to 78/22 by raising the reaction temperature from — 25 °C to 0°C (equation 47). This is in agreement with the FMO theory, since initial Lewis acid complexation is with the phosphonate group. [Pg.368]

C. Glycine is the major inhibitory amino acid transmitter in the spinal cord, and strychnine is a relatively selective antagonist of glycine. Strychnine has very little if any action at the GABA receptor-chloride channel complex. [Pg.353]

Using a typical poly (vinyl chloride) (PVC)-based membrane with different ionophores - Zn-bis(2,4,4-trimethylpen-tyl) dithiophosphinic acid complex [450], protoporphyrin IX dimethyl ester [451], porphyrin derivative [452] and hemato-porphyrin IX [453], tetra(2-aminophenyl) porphyrin [454], cryptands [455, 456], 12-crown-4 [457], benzo-substituted macro-cyclic diamide [458], 5,6,14,15-dibenzo-l, 4-dioxa-8,l 2, diazacyclopentadecane-5,14-diene [459], and (A-[(ethyl-l-pyrrolidinyl-2 -methyl) ] methoxy-2-sulfamoyl-5 -benza-mide [460] - the sensors for zinc ions were prepared and investigated. The armed macrocycle, 5,7,7,12,14,14-hexamethyl-1,4,8,11 -tetraazacyclo tetradeca-4,11 -diene dihydrogen perchlorate was used for the preparation of polystyrene-based Zn(II)-sensitive electrode [461]. [Pg.754]

Ethyl-3-methylpyridine (also known as aldehyde-collidine ) has been prepared by heating aldehyde-ammonia aldehyde-ammonia and acetaldehyde or paraldehyde aldol-ammonia and ammonia paraldehyde and ammonia <> 11,12 acetamide,1 or acetamide and phosphorus pentoxide ethylene glycol and ammonium chloride ethylidene chloride or bromide and ammonia ethylidene chloride and acetamide, ethylamine, or n-amylamine crotonic acid and a calcium chloride-ammonia complex 1 and by passage of acetylene or acetaldehyde and ammonia over alumina and other catalysts. [Pg.22]

In the presence of aluminum chloride, which presumably lowers the energy of the LUMO of the heterodiene by Lewis acid complexation, electron-rich alkenes give dihydropyrans on reaction with acyl cyanides at room temperature (82AG(E)859). Unsaturated esters further extend the range of diene components of value in these Diels-Alder reactions with inverse electron demand (82TL603). [Pg.772]

Hydrocarboxylation of Polyunsaturated Fatty Acids and Esters with a Palladium Chloride— Triphenylphosphine Complex Catalyst... [Pg.154]


See other pages where Chlorides, acid complex is mentioned: [Pg.19]    [Pg.558]    [Pg.257]    [Pg.527]    [Pg.283]    [Pg.116]    [Pg.279]    [Pg.406]    [Pg.51]    [Pg.388]    [Pg.1]    [Pg.6]    [Pg.316]    [Pg.50]    [Pg.48]    [Pg.478]    [Pg.107]    [Pg.156]    [Pg.272]    [Pg.116]    [Pg.322]    [Pg.779]    [Pg.311]    [Pg.396]    [Pg.140]    [Pg.573]    [Pg.626]    [Pg.237]    [Pg.427]    [Pg.382]   
See also in sourсe #XX -- [ Pg.228 ]

See also in sourсe #XX -- [ Pg.228 ]




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Chloride complex

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