Naphthalenes, 0-halo

To derive the maximum amount of information about intranuclear and intemuclear activation for nucleophilic substitution of bicyclo-aromatics, the kinetic studies on quinolines and isoquinolines are related herein to those on halo-1- and -2-nitro-naphthalenes, and data on polyazanaphthalenes are compared with those on poly-nitronaphthalenes. The reactivity rules thereby deduced are based on such limited data, however, that they should be regarded as tentative and subject to confirmation or modification on the basis of further experimental study. In many cases, only a single reaction has been investigated. From the data in Tables IX to XVI, one can derive certain conclusions about the effects of the nucleophile, leaving group, other substituents, solvent, and comparison temperature, all of which are summarized at the end of this section. 

The reactivities of 4- and 2-halo-l-nitronaphthalenes can usefully be compared with the behavior of azine analogs to aid in delineating any specific effects of the naphthalene 7r-electron system on nucleophilic substitution. With hydroxide ion (75°) as nucleophile (Table XII, lines 1 and 8), the 4-chloro compound reacts four times as fast as the 2-isomer, which has the higher and, with ethoxide ion (65°) (Table XII, lines 2 and 11), it reacts about 10 times as fast. With piperidine (Table XII, lines 5 and 17) the reactivity relation at 80° is reversed, the 2-bromo derivative reacts about 10 times as rapidly as the 4-isomer, presumably due to hydrogen bonding or to electrostatic attraction in the transition state, as postulated for benzene derivatives. 4-Chloro-l-nitronaphthalene reacts 6 times as fast with methanolic methoxide (60°) as does 4-chloroquinoline due to a considerably higher entropy of activation and in spite of a higher Ea (by 2 kcal). ... 

The rate of amination and of alkoxylation increases 1.5-3-fold for a 10° rise in the temperature of reaction for naphthalenes (Table X, lines 1, 2, 7 and 8), quinolines, isoquinolines, l-halo-2-nitro-naphthalenes, and diazanaphthalenes. The relation of reactivity can vary or be reversed, depending on the temperature at which rates are mathematically or experimentally compared (cf. naphthalene discussion above and Section III,A, 1). For example, the rate ratio of piperidination of 4-chloroquinazoline to that of 1-chloroisoquino-line varies 100-fold over a relatively small temperature range 10 at 20°, and 10 at 100°. The ratio of rates of ethoxylation of 2-chloro-pyridine and 3-chloroisoquinoline is 9 at 140° and 180 at 20°. Comparison of 2-chloro-with 4-chloro-quinoline gives a ratio of 2.1 at 90° and 0.97 at 20° the ratio for 4-chloro-quinoline and -cinnoline is 3200 at 60° and 7300 at 20° and piperidination of 2-chloroquinoline vs. 1-chloroisoquinoline has a rate ratio of 1.0 at 110° and 1.7 at 20°. The change in the rate ratio with temperature will depend on the difference in the heats of activation of the two reactions (Section III,A,1). 

Hydrogen-deuterium exchange in diazoalkanes, 53, 43 HYDROGENOLYSIS OF CARBON-HALO-GEN BONDS WITH CHROMIUM (II)-EN PERCHLORATE NAPHTHALENE FROM 1—BROMONAPHTHALENE, 52, 62... 

The critical separation distance calculated from the quenching data was found to be 13 A which is of the same order as the van der Waals separation. The critical separation distance remained unchanged when halogen substituted naphthalenes were used. The halo-substitution is expected to increase T1A SoA transition probability in naphthalenes. Since oscillator strengths / (naphthalenes /(iodonaphthalenes) is as 1 1000, no increase in transfer efficiency is clear indication of the lack of dependence on the oscillator strength. 

Halogenated hydrocarbons Chlorinated paraffins naphthalenes Chlorowax Halo wax Seekay wax Diamond Alkali Co Union Carbide Carbon Co ICI... 

Quantitative Property-S T) Relationship Dickhut et al. [67] developed a QP-5VV(7 )R based on experimental mole fraction solubilities for alkylbenzenes, PAHs, PCBs, chlorinated dibenzofuranes and p-dioxins, and alkyl- and halo-substituted naphthalenes and p-terphenyls in the range 4 to 40°C ... 

This correlation includes seven methy- and four halo-substituted benzenes, three heterocyclic compounds, and two phenols, along with benzene, naphthalene, and -NH2, -OCH3, -CN, -N02, -CHO, vinyl, and phenyl-substituted benzene. For aromatics, the range of values was only a factor of 5, and all data are within a factor of 1.6 of the correlation line therefore, simple calculations were likely to give data of about the same accuracy as experimental measurements (see Figure 5.31). 

Stereoselective synthesis of perylenequinones. Synthesis of the symmetrical perylenequinone phleichrome (4) has been effected by coupling of two identical naphthalene units to provide a binaphthol, which is then oxidized to a perylenequinone. Thus the bromonaphthalene 1 on halo-lithium exchange (f-BuLi) followed by reaction of anhydrous FeCl3 dimerizes to two optically active binaphthyls, (+)-and (— )-2, with 3 1 diastereoselectivity. 

In the reaction of 1-naphthoxide ions, a mixture of 2- and 4-aryl-, along with 2,4-diaryl-l-naphthol, is formed. However, substitution occurs only at C4 with the 2-Me-substituted anion (50-70% yields) [1[. On the other hand, 2-naphthoxide ions react with ArX to give substitution only at Cj of the naphthalene ring [32, 33]. The reactivity of the 2-naphthoxide ions allows the synthesis of naphthylpyridines, naphthylquinolines, and naphthylisoquinolines via their coupling reactions with the corresponding halo arenes, in good to excellent yields (50-95%) [33], The photostimulated reaction between 2-naphthoxide ions and l-iodo-2-methoxy-naphthalene was explored in liquid ammonia, as a novel approach to the synthesis of [1,1 ] binaphthalenyl-2,2 -diol (BINOL) derivatives (Scheme 10.23). This procedure has also been applied to the synthesis of BINOL in moderate yield (40%), which represents the first report of an SRN1 reaction in water [34]. 

The formation of norcaradiene derivatives with naphthalene [reaction (22)] lends some support to this scheme. This mechanism resembles a bimolecular two-step process suggested for the reaction of chloromethyl-aluminum compounds with olefins (199-201). On the other hand, a bimolecular one-step methylene transfer mechanism is generally accepted for the formation of cyclopropane derivatives by the reaction of halo-methylzinc compounds with olefins. This difference between the mechanism proposed for the cyclopropane formation from olefin and that for the ring expansion of aromatic compound may be ascribable to the difference in the stability of intermediates the benzenium ion (XXII) may be more stable than an alkylcarbonium ion (369). 

The activation produced by the ring-nitrogens in bicyclic azines is based on the increase in reactivity over that in the corresponding naphthalenes. The difference in reactivity of i- and 2-halo-naphthalenes (Table IX) toward piperidine - is slight the relation of their kinetic parameters is not consistent. At 200°, the... 

The loss of halide ion from the radical anions of aromatic compounds is a facile reaction in solution. This reaction has been studied extensively by electrode techniques (Lawless and Hawley, 1969a,b Bartek et al., 1970, 1972 Nadjo and Saveant, 1971a Houser et al., 1973 Nelson et al., 1973 M Halla et al., 1978, 1980 Saveant and Thiebault, 1978 Gores et al., 1979 Pinson and Saveant, 1974, 1978 Amatore e/a/., 1979 Parker, 1981k,l). The anion radicals of halonitrobenzenes, halobenzonitrilies, haloanthracenes, halo-naphthalenes, halobenzophenones and haloacetophenones have received the most attention. 

When the naphthalene ring is substituted, two products are generally formed , with production of an adduct involving the substituted ring being preferred (equation 68), Sometimes the reaction is very efficient and highly regioselective (equation 69) . When amino, halo or acyl substituents are involved the reaction is very inefficient. 

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