Naphthalene reduction with

Reactions other than those of the nucleophilic reactivity of alkyl sulfates iavolve reactions with hydrocarbons, thermal degradation, sulfonation, halogenation of the alkyl groups, and reduction of the sulfate groups. Aromatic hydrocarbons, eg, benzene and naphthalene, react with alkyl sulfates when cataly2ed by aluminum chloride to give Fhedel-Crafts-type alkylation product mixtures (59). Isobutane is readily alkylated by a dipropyl sulfate mixture from the reaction of propylene ia propane with sulfuric acid (60). 

Treatment with two equivalents of tert-butyl hypochlorite and subsequent reduction with sodium/naphthalene. 

Many expensive reductions such as the Birch reduction of naphthalene to isotetralin, benzene to cyclohexene, with metallic sodium and liquid ammonia, or reduction with LiAlHa, can generally be carried out electrochemically at much lower cost and under safe conditions. Electrochemical processes allow fluorinations to be carried out without using fluorine gas. Conducting polymers have been made by electrochemical processes which operate under ambient conditions, and the polymer can be synthesized, doped and shaped in film form in a single step. 

A recent experiment compared for the first time pollutant degradation by chemotactic bacteria and nonchemotactic mutants [54]. The result suggested an important role of chemotaxis in the bioremediation of contaminated soils. In a heterogeneous system, in which naphthalene was supplied from a microcapillary, a 90% reduction in the initial amount of naphthalene took six hours with the chemotactic wild-type Pseudomonas putida PpG7, while a similar reduction with either a chemotaxis-negative or a nonmotile mutant strain took about five times longer. Only the systems inoculated with the chemotactic strain exhibited degradation rates in excess of the rate of naphthalene diffusion from the... 

Apart from PET-reductive cyclization, chemical reduction has also been applied to the total synthesis of natural products such as capnellenediol 186 [184]. Naphthalene sodium is shown to be a suitable oxidant for generating ketyl radical anions which cyclize efficiently in a 5-exo-dig mode. In contrast, electroreductive cyclization of 184 does not lead to 185, but exclusively to the thermodynamically preferred 5-exo isomer with a remaining double bond in the endocyclic position [185] (Scheme 35). The steroid precursor 4.5-secocholes-tan-5-one 187, in which the lOa-side chain is varied, has been cyclized under the same conditions [186-188] (Scheme 36). Reduction with naphthalene sodium or sodium in ether exclusively produces the A B-cis steroid 188 with an exo double... 

Reduction is defined as acceptance of electrons. Electrons can be supplied by an electrode - cathode - or else by dissolving metals. If a metal goes into solution it forms a cation and gives away electrons. A compound to be reduced, e.g. a ketone, accepts one electron and changes to a radical anion A. Such a radical anion may exist when stabilized by resonance, as in sodium-naphthalene complexes with some ethers [122], In the absence of protons the radical anion may accept another electron and form a dianion B. Such a process is not easy since it requires an encounter of two negative species, an electron and a radical anion, and the two negative sites are close together. It takes place only with compounds which can stabilize the radical anion and the dianion by resonance. 

Many reductions with sodium are carried out in boiling alcohols in methanol (b.p. 64°), ethanol (b.p. 78°), butanol (b.p. 117-118°), and isoamyl alcohol (b.p. 132°). More intensive reductions are achieved at higher temperatures. For example reduction of naphthalene with sodium in ethanol gives 1,4-dihydronaphthalene whereas in boiling isoamyl alcohol tetralin is formed. 

Other methods that use 55 anions as precursor for the synthesis of fullerene-derivatives usually involve chemical formation of the anion. Alkylation of 55 has been accomplished, e.g. by reduction with propanethiol and potassium carbonate in DMF [91,92], sodium methanethiolate in acetonitrile [93], the naphthalene radical anion in benzonitrile[94], potassium naphthalide [95] or simply with zinc [96]. 

Naphthaldehyde has been made from a-naphthonitrile by reduction with stannous chloride, and from naphthalene by the action of aluminum chloride, hydrogen cyanide, and hydrochloric acid. The best preparation is the Sommelet reaction from a-chloro- or a-bromomethylnaphthalene and hexamethylenetetramine in aqueous alcohol is.is. .is.w or glacial acetic acid. This method has been improved in the present procedure by the use of 50% acetic acid as solvent. 

Deoxygenation of naphthalene-1,4-endoxides. A new method for conversion of these Diels-Alder adducts of benzynes with furanes to naphthalenes consists in reduction with sodium borohydride in trifluoroacetic acid.5 Excess acid is used when the substrate bears methyl groups at the bridgeheads. Substrates lacking such groups tend to undergo acid-catalyzed rearrangement to naphthols, but are reduced satisfactorily with THF as solvent and a limited amount of acid. 

Reduction of trichloroethylene by a series of well-characterized outer-sphere electron-transfer reagents, viz. the radical anions of naphthalene, pyrene, perylene, decamethylcobaltocene, and cobaltocene, resulted in the formation of cis- and trans-dichloroethylene in ratio varying from 0.87 to 4.5, whereas in the reduction by vitamin B12, the ratio was 30 1. This indicated that reduction with vitamin B12 occurs with a non-outer-sphere electron-transfer mechanism. A mechanism involving initial formation of a radical ion followed by an ejection of a chloride to give d.v-dichlorovinyl radical and franx-dichlorovinyl radical has been proposed.284... 

Reduction with sodium naphthalene of easily obtained diazadiene ruthenium ) complexes of type 65 (X = Cl) affords (rj6-arene)Ru(0) complexes 64. The latter are very reactive and undergo oxidative addition with iodine or alkyl halides to produce complexes 65 (X = I and X = CH2R, respectively) (51) [Eq. (26)]. Other ruthenium(O) complexes have been... 

Radical cations have also been trapped with the hydride ion. Irradiation of aromatic hydrocarbons such as phenanthrene, anthracene and naphthalene in aqueous acetonitrile containing sodium borohydride and an electron acceptor produces the dihydroarenes (Yasuda et ai, 1981b). With monoalkyl naphthalenes reduction in both the unsubstituted and substituted rings occurs... 

Naphthalene is reduced to 1,4-dihydronaphthalene by sodium and alcohol. Isomerization of this product to 3,4-dihydronaphthalene occurs with sodamide in liquid ammonia. Tetrahydronaphthalene (tetralin) is formed from naphthalene by sodium in amyl alcohol or by reduction with nickel-aluminum alloy and aqueous alkali. Catalytic hydrogenation of naphthalene can be stopped at the tetralin stage over copper chromite, Raney nickel, or alkali metal catalysts. cis-Decahydronaphthalene is produced by high-pressure hydrogenation of tetralin over Adams catalyst, whereas a mixture of cis- and trans-decalins is obtained from naphthalene under the same conditions. ... 

As mentioned above, one major drawback of the Trost methodology is its restriction to the parent compound. It was the Cohen group who found an alternative approach to phenylthiocyclopropyl lithium chemistry by using a reductive lithiation of readily accessible cyclopropanone dithioketals which also works for alkyl-substituted cyclopropanes. The anions obtained by reduction with two equivalents of lithium naphthalene or preferably lithium l-(dimethylamino)naphthalene (LDMAN) can effectively be trapped by apt electrophiles (equation 112). 

Derivatives of anthracene are seldom prepared from anthracene itself, but rather by ring-closure methods. As in the case of naphthalene, the most important method of ring closure involves adaptation of Friedel-Crafts acylation. The products initially obtained are anthraquinones, which can be converted into corresponding anthracenes by reduction with zinc and alkali. This last step is seldom carried out, since the quinones are by far the more important class of compounds. 

As discussed above, the absolute stereochemistry of halenaquinone (+)-l and halenaquinol (+)-2 has been theoretically determined by the calculation of the CD spectra of naphthalene-diene derivatives by means of the tt-electron SCF-CI-DV MO method. 18 To apply the same method to these xestoquinone compounds, xesto-quinol dimethyl ether (+)-74 was converted to naphthalene-diene derivative 75 by reduction with sodium borohydride in the presence of cerium(IIl) chloride23 and methanol, followed by treatment with pyridinium p-toluenesulfonate and methanol (Scheme 16).20 The product obtained was a mixture of two stereoisomers of the methoxyl group at the 4-position, from which a single isomer 75 was isolated as... 

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