Toluene, solvent

Insofar as they are used to purify other products, several processes used in the refinery fall under the classification of dewaxing processes however, such processes must also be classified as wax production processes (2). Most commercial dewaxing processes utilize solvent dilution, chilling to crystallize the wax, and filtration (28). The MEK process (methyl ethyl ketone—toluene solvent) is widely used. Wax crystals are formed by chilling through the walls of scraped surface chillers, and wax is separated from the resultant wax—oil—solvent slurry by using fliUy enclosed rotary vacuum filters. 

Gosorb Process. Like the copper—Hquor scmbbing method, the Cosorb process also reHes on the formation of a cuprous complex of carbon monoxide but uses a nonaqueous organic solvent. The preferred system uses a cuprous tetrachloroalurninate toluene complex in a toluene solvent (90). Many other organometaUic complex variants have been proposed (91—93) but have not been commercialized. 

The (9-cresol novolaks of commercial significance possess degrees of polymerization, n, of 1.7—4.4 and the epoxide functionaUty of the resultant glycidylated resins varies from 2.7 to 5.4. Softening points (Durran s) of the products are 35—99°C. The glycidylated phenol and o-cresol—novolak resins are soluble in ketones, 2-ethoxyethyl acetate, and toluene solvents. The commercial epoxy novolak products possess a residual hydrolyzable chlorine content of <0.15 wt% and a total chlorine content of ca 0.6 wt % (Table 2). 

The reactions of oxiranes with thiocyanate ion or with thiourea are usually done in homogeneous solution in water, alcohols or alcohol-acetic acid. The use of silica gel as a support for potassium thiocyanate in toluene solvent is advantageous for the simple work-up (filtration and evaporation of solvent) (80JOC4254). A crown ether has been used to catalyze reactions of potassium thiocyanate. 

A recently discovered variant of the Wallach technique is the silver ion cata lyzed fluorination of aryl diazo sulfides in hydrogen fluonde-pyridine-toluene solvent [57] (equation 12) Electron withdrawing substituents such as acetyl give higher yields of aryl fluoride (71%) than electron donating groups (butyl 39%, methoxy, 2-14%), reductive dediazoniation competes with fluorination... 

Homogeneous Solution Counting. This method is used for expls soluble in the toluene solvent. 

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). 

To confirm the production of benzene from the decomposition reaction of methyl(triphenylmethyl)dichlorosilane, the decomposition reaction of methyKdi-phenylmethyl)dichlorosilane in the presence of aluminum chloride was carried out in toluene solvent at 80 C. In this reaction, the exchange reaction between phenyl groups on the methyl group of (diphenylmethyl)(inethyl)dichlorosilane and toluene occurred to give [phenyl(tolyl)methylJ(methyl)dichlorosilane and (di-tolylmethyl)(methyl)dichlorosiIane (Scheme 1). " ... 

Close approaches of arene. solvents to metalloporphyrins have been observed by crystallography. For example. Mn(TPP) crystallizes as a toluene. solvate with a toluene solvent molecule lying on either side of the porphyrin plane. The dihedral angle between the porphyrin plane and toluene plane is 10.7 (reduced to 6.7 for one of the pyrrole rings). The average perpendicular distance between the toluene ring and the mean 24-atom plane of the porphyrin is 3.30 A. One aromatic C—C bond of toluene approximately eclipses one N—Mn—N axis, with IVln- C distances of 3.05 and 3.25 There has been considerable effort invested in the... 

Organic solvent can affect the enzyme specificity [76]. Authors have indicated that transesterification of l,4-butyloxy-2-octylbenzene and butanol in presence of lipases from Pseudomonas can produce two different products when using hydrophilic (acetonitrile) or hydrophobic (toluene) solvents. Zaks and Klibanov [16], demonstrated that subtilisine and a-chymotrypsine specificites can be changed as a function of solvent types. This is true for a limited number of biocatalysts. 

Applications Caceres et al. [114] compared various methods for extraction of Tinuvin 770 and Chimas-sorb 944 from HDPE pellets, namely room temperature diffusion in CHC13 (20 % extraction), ultrasonica-tion (20% extraction), Soxtec extraction with DCM (nonsolvent) (50 % extraction), dissolution (dichloroben-zene)/precipitation (2-propanol) (65-70% recovery) and boiling under reflux with toluene (solvent) at 160 °C (95 % extraction). By changing conditions (nature of solvent, T, t) similar comparisons do not have much added value. Table 3.6 compares the results of reflux extraction and MAE for additives in LDPE [115]. 

The ester is made by adding benzyl alcohol slowly to a preformed solution of phosgene in toluene at 12-16°C, toluene solvent finally being distilled off under vacuum. When discoloured phosgene was used (probably containing iron salts from corrosion of the cylinder), a violent explosion occurred during the distillation phase, presumably involving iron-catalysed decomposition of the chloroformate ester. 

Several palladium catalysts for formation of aryl sulfides from aryl halides have been investigated more recently. A combination of Pd2(dba)3 and DPEphos catalyzed the formation of a broad range of diaryl sulfides in the presence of 1 mol.% palladium and NaO-t-Bu base in toluene solvent.12,rThe highest yields of alkyl aryl sulfides were obtained from aryl triflates and n-butyl thiol catalyzed by a combination of palladium acetate and BINAP. However, these reactions contained 10 mol.% catalyst, were long, and required deactivated aryl triflates. A combination of Pd2(dba)3 and DPPF catalyzed the coupling of thiols with resin-bound aryl halides.121... 

Using a protocol for tandem carbonylation and cycloisomerization, Mandai et al.83 were able to synthesize cyclopentene and cyclohexene derivatives in high yield, including fused and 5/>/>0-bicycles (Scheme 25). The cyclohexene Alder-ene products were not isolable methanol addition across the exocyclic double bond (in MeOH/ toluene solvent) and olefin migration (in BuOH/toluene solvent) were observed. The mechanism of methanol addition under the mild reaction conditions is unknown. In contrast to many of the other Pd conditions developed for the Alder-ene reaction, Mandai found phosphine ligands essential additionally, bidentate ligands were more effective than triphenylphosphine. 

Since most of our observations on the reacting systems were made by means of conductivity measurements it is necessary to remember that in these systems the only factor which increases conductivity is an increase in the concentration of ions, but that a decrease of conductivity could be due to any or all of the following effects increase of size of cation by polymerisation, increase of viscosity of solvent due to polymer, occlusion of ions in precipitated polymer, trapping of polymer between the electrodes. A similar list was given by Matyska in one of the earliest applications of conductivity measurements to a cationic polymerisation, that of isoprene by aluminium bromide in toluene solvent [19]. 

The statement in the last paragraph of the paper, that benzene is unlikely to be a chain-breaker, is strange in view of the fact that this author himself discovered the alkylation of toluene (solvent) by the growing cation during cationic polymerisations [15-17, 28], which is a transfer reaction. 

In dry 25-mL volumetric flasks, prepare four calibration standards of isopropyl alcohol in toluene solvent that are 20, 30, 40, and 50% in alcohol concentration. Obtain an unknown from your instructor and dilute to the mark with toluene. Shake well. 

Toluene Solvent, perfumes, detergents, dyes, water-based adhesives, moulding tape, wallpaper, calcium silica sheet, paint, carpeting, carpet adhesives, grease solvents. 29 3... 

Condensations carried out for 2 hr. at reflux in either toluene (solvent A) or THE (solvent B). 

Abstract Titration of weak bases in non-aqueous solvents can provide valuable information about these weak bases. Some primary amines 1-aminobutane, 1-aminopropane, 2-aminoheptane, aminocyclohexane, 3-amino-l-phenylbutane were titrated with hydrochloric acid in toluene solvent. All the primary amines gave very well-shaped potentiometric titration curves. The same titrations were done with hydrochloric acid in methanol solvent to show the effect of amphiprotic solvent in the titrations with hydrochloric acid. 

A11 reactions were carried out under N2, using anhydrous conditions, with 5% nucleophile. Mole % relative to substrate. Isolated Yields. Toluene solvent. Chlorobenzene solvent. o-Dichlorobenzene solvent. 

The synthesis of the bis(amino) aryl ether ketimine oligomer was carried out in an analogous fashion to the poly(aryl ether) oligomers described before (Scheme 5) [43]. The ketimine functional 4,4 -bisfluoride was reacted with hyd-roquinone and 3-aminophenol in an NMP/toluene solvent mixture in the presence of potassium carbonate. The characteristics of the oHgomer synthesized are shown in Table 1 (sample le). 

Although the chiral ketoiminatomanganese(lll) complexes were reported to catalyze the asymmetric aerobic alkene epoxidations, an aldehyde such as pivalaldehyde is required as a sacrihcial reducing agent. Groves reported that the dioxo(porphyrinato)ruthenium complexes 31, prepared with m-chloroperoxyben-zoic acid, catalyzed the aerobic epoxidation without any reductant. " On the basis of these reports, Che synthesized the optically active D4-porphyrin 35 and applied it to the truly aerobic enantioselective epoxidation of alkenes catalyzed by the chiral frani-dioxo (D4-porphyrinato)ruthenium(Vl) complex. The dioxoruthenium complex catalyzed the enantioselective aerobic epoxidation of alkenes with moderate to good enantiomeric excess without any reductant. In the toluene solvent, the turnovers for the epoxidation of T-(3-methylstyrene reached 20 and the ee of the epoxide was increased to 73% ee. 

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