6-Methyl-2-bromonaphthalene

Methyl-2-bromonaphthalene does not form a Grignard reagent satisfactorily in ether or ether-benzene, but with use of THF the reagent is obtained readily in high yield."... 

Aryl methyl ketones have been obtained [4, 5] by a modification of the cobalt-catalysed procedure for the synthesis of aryl carboxylic acids (8.3.1). The cobalt tetracarbonyl anion is converted initially by iodomethane into the methyltetra-carbonyl cobalt complex, which reacts with the haloarene (Scheme 8.13). Carboxylic acids are generally obtained as by-products of the reaction and, in several cases, it is the carboxylic acid which predominates. Unlike the carbonylation of haloarenes to produce exclusively the carboxylic acids [6, 7], the reaction does not need photoinitiation. Replacement of the iodomethane with benzyl bromide leads to aryl benzyl ketones in low yield, e.g. 1-bromonaphthalene produces the benzyl ketone (15%), together with the 1-naphthoic acid (5%), phenylacetic acid (15%), 1,2-diphenylethane (15%), dibenzyl ketone (1%), and 56% unchanged starting material [4,5]. a-Bromomethyl ketones dimerize in the presence of cobalt octacarbonyl and... 

Chemical/Physical. An aqueous solution containing chlorine dioxide in the dark for 3.5 d oxidized naphthalene to chloronaphthalene, 1,4-dichloronaphthalene, and methyl esters of phthalic acid (Taymaz et ah, 1979). In the presence of bromide ions and a chlorinating agent (sodium hypochlorite), major products identified at various reaction times and pHs include 1-bromonaphthalene, dibromonaphthalene, and 2-bromo-l,4-naphthoquinone. Minor products identified include chloronaphthalene, dibromonaphthalene, bromochloronaphthalene, bromo-naphthol, dibromonaphthol, 2-bromonaphthoquinone, dichloronaphthalene, and chlorodibromo-naphthalene (Lin et ah, 1984). 

D iphenylmethane 1-Bromonaphthalene Chloroform l-Chloronaphthalene(m.p. 55) Ethyl alcohol Isoamyl benzoate Isoamyl oxalate Isoeugenol methyl ether Methanol... 

A translucency liquid in current use is a mixture in equal amounts, of ix-bromonaphthalene and paraffin (G14), but many other solutions have been proposed, including methyl salicylate (L3), 2% sodium carbonate dissolved in equal parts of water and methanol (P6), and Soalex NB (K13). Anisole (P19) is also recommended because reading can be done within 20 minutes, air bubbles seem easy to eliminate, and anisole itself evaporates spontaneously afterward. Sonnet used ethanol for glycoproteins (S22). Some types of varnish have proved useful (D7), but as they dry rather slowly we ourselves have abandoned their use. 

In the dehalogenation of 4-chlorobiphenyl, 1-chloro- and 1-bromonaphthalene, 9-chloro- and 9-bromoanthracene and 4-chlorobenzonitrile, diethyl sulphide has been used as electron donor397. The involvement of radical anions in these reactions is evidenced by the incorporation of deuterium into the products when the reactions were performed in acetonitrile-deuterium oxide. Lithium diisopropylamide in hexane or tetrahydrofuran398 and sodium methyl siliconate (MeSi03Na3)399 have also been used as electron transfer reagents in the photodehalogenation of 4-chlorobiphenyl. 

C9H8S 2-methyl benzothiophene 1195-14-8 gas 1.124 2 18601 C10H7Br 1-bromonaphthalene 90-11-9 liquid 1.290 1... 

Most compounds whose lowest excited singlet state is an (n,jr ) state exhibit only very weak fluorescence. The reason is that due to spin-orbit coupling, intersystem crossing into an energetically lower triplet state is particularly efficient. (Cf. Section 5.2.2.) Heavy atoms in the molecule (e.g., bromonaphthalene) or in the solvent (e.g., methyl iodide) may favor intersystem crossing among states to such an extent that fluorescence... 

By this method, 1-bromonaphthalene affords 1-naphthonitrile in 94% yield after refluxing for 4 hrs. with pyridine as solvent the reaction mixture is heated in an oil bath at 215-225° for 15 hrs., and the yield is 82-90%. Efficient procedures for liberating the nitrile from the cuprous halide complex involve pouring the brown reaction mixture into an aqueous solution of ferric chloride (oxidizes Cu+ to Cu ", which forms no complex), ethylenediamine (forms complexes with Cu+ and Cu " ), or sodium cyanide (forms soluble sodium cuprocyanide). The higher-boiling N-methyl-2-pyrrolidone (b.p, 202°) is also satisfactory, but is more expensive. 

Our plan was to connect the two 7-methyljuglone units D and I by Suzuki-Miyaura coupling. Diospyrin (58) is reported to be optically inactive, and there is no restricted rotation around the connecting bond between C-2 and C-6. It therefore seemed possible to connect D and I at the positions C-2 and C-6 under conventional conditions. Diels-Alder reactions were employed to prepare D and I. Accordingly, Diels-Alder cycloaddition between A and B gave C, which was methylated to furnish D. Similarly, the adduct G was prepared from E and F. The naphthoquinone G was converted to boronic acid I via bromonaphthalene H. 

Methyl caprylate Isobutyl carbonate 1 -Bromonaphthalene 1 -Chloronaphthalene Naphthalene... 

Lipkowski, J. Sgarabotto. P. Andreetti. G.D. Clathrate inclusion compounds of bisiisothiocymsito)tetrakis(4-methylpyridine) nickel(II). I. Compounds with 2-methyl-and 2-bromonaphthalene as guest components. Acta Crystallogr.. Sect. B 1988. 36 (1). 51-57. 

Series I anthracene, benzene, biphenyl, 1-bromonaphthalene, 1-methylnaphthalene, naphthalene, pyrene, toluene and p-xylene. Series II-IV acetanilide, acetophenone, benzaldehyde, benzene, benzonitrile, benzyl alcohol, benzylamine, bromobenzene, butyrophenone, hexaphenone, methyl benzoate, methyl phenyl ether, nitrobenzene, propiophenone, toluene and valerophenone. Series V-VI acetophenone, anthracene, benzaldehyde, benzene, benzonitrile, benzyl alcohol, butyrophenone, chlorophenone, naphthalene, nitrobenzene and propiophenone. 

Similar to the reaction with urea anion, the photostimulated reaction of 1-bromonaphthalene with selenobenzamide and selenourea anions afforded methyl-1-naphthyl selenide after quenching the reaction with Mel [68]. The Se nucleophile can be formed by reaction of Se and Na metals in liquid ammonia and reacts under irradiation with Phi to give (PhSe) (78%) after oxidation of the PhSe" ions formed [69]. The reaction of PhSe" or PhTe" with ArX under irradiation straightforward and scrambled products are obtained and depends on the ArX employed [59, 70]. 

Alkyl substituent groups on an aromatic ring introduce new modes of interaction, and perhaps distortion, without the complicating effects of jr-elec-tron donation or withdrawal because alkyl groups are essentially electronically innocuous. Almost all of the thermochemical literature on substituted aromatic species relates to benzene derivatives. There are comparatively few enthalpy of formation measurements for substituted naphthalenes. It has been shown in those few cases that the difference between enthalpies of formation of the 1- and 2-isomers is generally small, and the difference between the naphthalene and benzene derivatives is largely independent of the substituent. For example, the enthalpies of formation of 1- and 2-bromonaphthalene are 174.3 5.6 and 175.6 2.3 kj/mol. These values differ from that of bromobenzene (105.4 4.1 kJ/mol) by ca. 70 kJ/mol, very close to the enthalpy of formation difference between the parent hydrocarbons. For other aromatic hydrocarbons, there are almost no substituted derivatives other than methylated ones. 

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