Tetralins, 1-functionalized

Sodium LAS synthesized via aluminum chloride catalysis dissolves better than sodium LAS from the hydrogen fluoride route. The main difference is the tetralin content. Dialkyltetralinsulfonates (DATs) function as hydrotropes and this influence can be larger than that of the 2-phenylalkane content. For a homolog (equal alkyl side chains), the higher the DAT content, the lower the... 

To determine the principal pathway of exchange, isotopic exchange by functional position was examined. The lower halves of Tables II and III show the amounts of incorporation of protium into the spent Tetralin. In E10, 66% was in the position, 23% in the position, and 11% in the Har position. A similar distribution was found in El9. This preferential incorporation in the Hx position of Tetralin strongly suggests that the predominant path-... 

To circumvent the problems of ring cleavage in cyclobutabenzene (38) and thereby extend the series, the related reaction of protodesilylation has been used. The rate constants and partial rate factors for protodesilylation of benzocycloalke-nes in perchloric acid-methanol at 50 °C were measured (Table 3). In this system the enhancement of rate between o-xylene (5) and tetralin (2) is much less dramatic, but the loss of a-reactivity as a function of decreasing ring size stands out clearly a factor of 15 separates the rates of a exchange for tetralin versus cyclobutaben-... 

The reactivities in abstraction toward the ROo radicals correlate poorly with the methyl data. For example, toward R02 radicals the cyclic olefins and Tetralin are as reactive as cumene (within a factor of about 2), while toward CH3 , Tetralin and cumene are at least 10 times more reactive than the cyclic olefins. This apparent lack of selectivity in abstraction by the peroxy radical is no doubt related to the factors controlling the selectivity in addition but to some degree is a function of the reactants. The peroxy radical appears to show a somewhat more typical selectivity (8, 18) toward a broad selection of aralkyl hydrocarbons, although the changes in exothermicity are more significant in this series. 

Figure 4. Initial oxidation rate of 7.25M Tetralin at 70°C. containing 0.02M ZnP as a function of AIBN concentration...

Equation E is consistent with linear dependence of oxidation rate on [AIBN], l/[ZnP], and [RH] as shown in Figures 1, 2, and 3, respectively, but it does not adequately describe the observed kinetics since it requires that the intercepts on the rate axis in Figures 2 and 3 should be equal. Equation D cannot be similarly ruled out since it is also clearly consistent with the linear dependence of rate on [AIBN] and 1/ [ZnP], while the dependence on [RH] is less obvious. Because of the illogical nature of the oxidation rate of Tetralin as a function of the zinc... 

Milton Denekas Isn t the solubility of coal in phenanthrene a function of temperature of extraction, and therefore a partial thermal cracking process Isn t this reaction somewhat different from the action of tetralin on coals since the latter solvent has hydrogen available for hydrogenation ... 

A combination of triflic acid with iodine was shown to be effective to liquefy three types of coal in toluene or tetralin under hydrogen pressure.141 The major role of acid was found to enhance coal depolymerization to asphaltenes, whereas the main function of iodine was to hydrogenate and hydrocrack asphaltenes to oils. The combined catalytic system removed 50% of the nitrogen and 90% of the sulfur of the coals (Illinois No. 6 and Pittsburg seam samples). 

The relationships of oxidation potential to radical reactivity index Sr and nucleophilic reactivity index Sn illustrated in Figure 4 are very similar to those with antioxidation and antiozonization, where the maximum values were observed at 0.4 and 0.25 volt. Therefore, antioxidation seems to proceed by a radical mechanism in contrast to the nucleophilic type of antiozonization. Indeed, the antioxidation effect of amines toward NR, SBR, BR, and HR is well correlated with radical reactivity as shown in Figures 5-8. The protection of SBR solution by amines from oxidative degradation and the termination of chain reaction in the oxygen-Tetralin system are also shown as functions of Sr in Figures 9 and 10. 

Figures 2 and 3 contain yield curves for naphthalene and 1-methylindan as a function of reaction time for tetralin and tetralin plus coal, pyrite, or asphaltene. The asphaltene was a homogenized mixture of several samples isolated from coal liquefaction products during other work in our laboratory (9). This asphaltene sample contained essentially a negligible ash content (<0.1%). Therefore, it contains many organic structures similiar to those found in coal, but unlike coal, its reactions will be free of any complicating factors due to mineral matter. The yields of naphthalene and 1-methylindan are greater in the presence of asphaltene than in its absence, although not quite as high as in the presence of coal. This is additional evidence that these two products arise mainly from reactions associated with the presence of the organic portion of coaly matter. These reactions are quite likely free radical in nature.

The results described above illustrate the problem of separating effects due to catalysis provided by pyrrhotite from those due to the chemistry of the reduction of pyrite. It must also be borne in mind that reduction of pyrite produces a nearly equivalent amount of l S, which remains available to enter subsequent reactions by mechanisms now only poorly understood. In order to remove these complications, pyrrhotite was prepared by the reduction of pyrite with tetralin, isolated from the reaction residue, and then heated with fresh tetralin. Figures 4 and 5 contain the yields of naphthalene and 1-methylindan, and the ratios of trans- to cis-decalin as a function of concentration. In this case, the pyrite was a hand-picked sample of micro-crystals taken from a coal nodule. As may be seen, the yields of naphthalene and 1-methylindan, and the ratio of trans- to cis-decalin all increase with pyrite concentration. The slope of the line for naphthalene yield is 0.91. A slope of 0.53 is calculated for stoichiometric reduction of FeS to FeS by tetralin to yield naphthalene. Thus, roughly half of the naphthalene produced can be accounted for by the demand for hydrogen in the reduction of pyrite. 

Figure 4. Yields of 1-methylindan and naphthalene and the ratio of trans/cis Decalin as a function of pyrite concentration after reaction with Tetralin at 450°C for 15 min...

FIGURE 43 Monolithic stirrer equipped with MIL101(Cr)-coated cordierite monoliths (left) and the performance as a function of time on stream in the oxidation of tetralin with t-butyl peroxide (720). 

Figure 17 shows the product yields of indirect brown coal hydrogenation with tetralin as a function of stratification and texture (lithotype... 

Figure 18, Carbon conversion achieved through indirect hydrogenation with tetralin as a function of the liptinite and huminite contents. (Reproduced with permission from Ref. 19. Copyright 1983, Schriftleitung Braunkohle.)...

In general, carbonyl groups do not function as good initiators in vinylsilane-mediated cyclization reactions and relatively few examples exist. The cyclization of vinylsilanes with ketones or aldehydes as initiators is a highly underdeveloped reaction that holds considerable potential. As reported by Tius and coworkers, treatment of aldehyde (13) with a catalytic amount of p-toluenesulfonic acid gave a mixture of the tetralins (14) and (15) in a combined yield of 53%, with lesser amounts of the enone (16 Scheme 8). The enone system presumably arises from the intramolecular 1,3-hydride transfer of the intermediate a-silyl carbocation (17). Similarly, the vinylsilane (18) undergoes cyclization to produce the disub-stituted benzene derivative (19), although yields are low. 

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