Toluene equivalents

Acetone, pesticide grade or equivalent Acetonitrile, pesticide grade or equivalent n-Hexane, pesticide grade or equivalent Toluene, pesticide grade or equivalent Boiling chips Olive oil, reagent grade Sodium hydroxide (50%, w/w)... 

Scheme 4 Palladium-catalyzed Heck reaction of aryl iodides." Reagents and conditions (i) PdAS-V, EtsN (1.5 equivalents), toluene, 100 °C.

The inflammable solvents most frequently used for reaction media, extraction or recrystallisation are diethyl ether, petroleum ether (b.p. 40-60° and higher ranges), carbon disulphide, acetone, methyl and ethyl alcohols, di-Mo-propyl ether, benzene, and toluene. Special precautions must be taken in handling these (and other equivalent) solvents if the danger of Are is to be more or less completely eliminated. It is advisable to have, if possible, a special bench in the laboratory devoted entirely to the recovery or distillation of these solvents no flames are permitted on this bench. 

Acetone in conjunction with benzene as a solvent is widely employed. With cyclohexanone as the hydrogen acceptor, coupled with toluene or xylene as solvent, the use of higher reaction temperatures is possible and consequently the reaction time is considerably reduced furthermore, the excess of cyclohexanone can be easily separated from the reaction product by steam distillation. At least 0 25 mol of alkoxide per mol of alcohol is used however, since an excess of alkoxide has no detrimental effect 1 to 3 mols of aluminium alkoxide is recommended, particularly as water, either present in the reagents or formed during secondary reactions, will remove an equivalent quantity of the reagent. In the oxidation of steroids 50-200 mols of acetone or 10-20 mols of cyclohexanone are generally employed. 

Pivalates. The selective pivaloylation of sucrose with pivaloyl (2,2-dimethylpropionyl) chloride has been thoroughly investigated (56). The reactivity of sucrose toward pivaloylation was shown to be significantly different from other sulfonic or carboxyflc acid chlorides. For example, reaction of sucrose with four molar equivalent of toluene-/)-sulfonyl chloride in pyridine revealed, based on product isolation, the reactivity order ofO-6 0-6 > 0-1 > 0-2 (57). In contrast, a reactivity order for the pivaloylation reaction, under similar reaction conditions, was observed to be 0-6 0-6 > 0-1 > 0-4. 

A here y is the number of equivalent positions. A partial rate factor calculation for nitration of toluene is given in Example 10.1. 

Katz et al. tested the theory further and measured the distribution coefficient of n-pentanol between mixtures of carbon tetrachloride and toluene and pure water and mixtures of n-heptane and n-chloroheptane and pure water. The results they obtained are shown in Figure 17. The linear relationship between the distribution coefficient and the volume fraction of the respective solvent was again confirmed. It is seen that the distribution coefficient of -pentanol between water and pure carbon tetrachloride is about 2.2 and that an equivalent value for the distribution coefficient of n-pentanol was obtained between water and a mixture containing 82%v/v chloroheptane and 18%v/v of n-heptane. The experiment with toluene was repeated using a mixture of 82 %v/v chloroheptane and 18% n-heptane mixture in place of carbon tetrachloride which was, in fact, a ternary mixture comprising of toluene, chloroheptane and n-heptane. The chloroheptane and n-heptane was always in the ratio of 82/18 by volume to simulate the interactive character of carbon tetrachloride. 

Figures 13.8 and 13.9 show the separation of polystyrene standards using a typical mixed-bed column and its calibration plot, respectively. The major advantages of using a large i.d. 10-mm column are low hack pressure and relatively short run times. As seen in Fig. 13.8,10 standards from toluene thru 8.4 X 10 MW can be resolved in a mere 21 min. Because of the large 10-mm i.d. columns, 1.5-ml/min flow rates give a linear velocity equivalent to that of only 0.9 ml/min using a 7.6-mm i.d. column. Also, the gel volume contained in one 10 mm i.d. X 500 mm column is 39.3 ml, whereas a 7.6 mm i.d. X 300 mm column contains only 13.6 ml of gel volume. This bulk volume factor, combined with the large pore volumes of gels, obtains essentially the same resolution as that obtained on three standard 7.6 X 300-mm columns in series, but in about one-half the usual time required using the smaller columns.

An intriguing class of persistent radicals are those formed by the one-electron oxidation of the hexagonal prismatic clusters Li2[E(N Bu)3] 2 (3.21, E = S, Se). The air oxidation of 3.21 produces deep blue (E = S) or green (E = Se) solutions in toluene. The EPR spectra of these solutions consist of a septet (1 3 6 7 6 3 1) of decets (Eig. 3.5). This pattern results from interaction of the unpaired electron with three equivalent 7=1 nuclei, i.e., and three equivalent I = 3/2 nuclei, i.e., Ei. It has been proposed that the one-electron oxidation of 3.21 is accompanied by the removal of an Ei" cation from the cluster to give the neutral radical 3.22 in which the dianion [S(N Bu)3] and the radical monoanion [S(N Bu)3] are bridged by three Ei" cations. 

A mixture of 50 parts of the distillate, 25.6 parts of 3-bromoethyl acetate, 10.7 parts of potassium carbonate and 400 parts of toluene is stirred at reflux temperature for 16 hours. The mixture is heated with water. The organic layer is separated, washed with water and extracted with dilute hydrochloric acid. The resulting extract is washed with benzene, rendered alkaline and extracted with benzene. The resulting benzene solution is dried over anhydrous potassium carbonate, filtered and concentrated. The residue is dissolved in 300 parts of ethanol and treated with 2.2 equivalents of a 25% solution of anhydrous hydrochloric acid in 2-pro-pa nol. The resulting crystals are recrystallized from 400 parts of ethanol and 10 parts of water. The dihydrochloride of N-( 3-acetoxyethyl)-N -[7-(2 -chloro-10 -phenothiazine)propyl] piperazine melts unsharply at about 200°C to 230°C. 

Figure 9-50. HETP and pressure drop data for a typical distillation system. Packing equivalent to X-200 (8 strands), stainless steel. System methylcyclohexane and toluene. Reflux Ratio 100%. Column Diameter 18 inches. Packed Height 5 feet. Used by permission ACS Industries, Inc., Separation Technology Division, Bull. B-129 (1992).

Monosubstitution can occur at any one of the six equivalent carbons of the ring. Most of the monosubstituted benzenes have common names such as toluene (methylbenzene), phenol (hydroxybenzene), and aniline (aminobenzene). 

Titration A process in which one reagent is added to another with which it reacts an indicator is used to determine the point at which equivalent quantities of the two reagents have been added, 84-85,92 Toluene, 589... 

The bis(imino-l5-phosphane) 1 reacts with a molar equivalent of an isocyanate in toluene at 20 C for 16 hours to give pyrazolo[3,4-<7]-l,3-diazepines 2. No further details were reported.167"b... 

The tricyclic 1,3-diazepines 3 are formed by the action of two molar equivalents of aromatic isocyanates on the bis(imino-A5-phosphane) 1 in toluene at 20 C for 16 hours in a tandem aza-Wittig [2 t 2]-cycloaddition reaction . No further details were reported.167... 

The tridentate ligands C, L and M are effective catalysts for the enantioselective addition of dialkylzincs to aromatic aldehydes16,17. In particular, ligands L and M qualify as members of the chemical enzyme (chemzyme) class of synthetic reagents17, since they function in a predictable, clear-cut mechanistic way. As demonstrated by X-ray diffraction, the actual catalyst is a monomeric zinc chelate 2 formed in toluene at 50 C by reaction of L or M with one equivalent of diethylzinc. 

A -(l-Phenylpropyl)amidcs 3 are enantioselectively synthesized by alkylation of acylimines 2 generated in situ from N-(amidobenzyl)benzotriazoles 1 with diethylzinc in the presence of an enantiomerically pure promoter [(— )-(l/ 2.V)-A,A-dibutylnorcphcdrine, DBNE], The best results are obtained with one equivalent of 1, one equivalent of DBNE and two or three equivalents of diethylzinc in toluene at —78 =C with slow warming to room temperature before workup11. 

The Lewis acid of choice for most of the cyclization reactions is ethylaluminum dichloride, because of its exceptional properties it is a mild Lewis acid, and, as an organometallic compound, can serve as a proton sponge , and thereby inhibit competitive protodesilyla-tion37. The desired precursors reacted smoothly with 1.1 equivalents of ethylaluminum dichloride in toluene or dichloromethane at low temperature to generate diastereoselectively the desired spiro[4.5]decanones38. 

The contribution of the carbon atoms from the 1- and 7- positions to TeNMe carbon were obtained by determining the specific activity of the TeNMe isolated from the nitration of toluene-1-14C and toluene-7-14 C, respectively. Similarly, by nitrating toluene-1,3,5-l4C, it was possible to determine the 3- and 5-contributions, since the contribution of the 1-position could be subtracted and the 3- and 5-positions were considered to be equivalent. Finally, the contributions of the 2-, 4- and 6-positions were determined from the nitration of toluene-2,4,6,7-14C by subtracting the contribution of the 7-position. An approximate contribution for each of these positions (2-, 4- and 6-) was obtained by considering them to be equivalent... 

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