Methoxynaphthalene

Table 12-2 gives some of Sterba s results for 1-naphthol, resorcinol, 1-methoxy-naphthalene, 3-methoxyphenol and 1,3-dimethoxybenzene. The data in the table show that the 1-naphthoxide ion is 108 times more reactive than the undissociated naphthol, which is 102 times more reactive than 1-methoxynaphthalene. The rate ratios for the monoanion of resorcinol relative to resorcinol, 3-methoxyphenol, and 1,3-dimethoxybenzene are of similar magnitudes. The dissociation of both OH groups of resorcinol gives rise to a rate constant (2.83 X 109 m -1 s-1) which, in our opinion, is probably mixing- or diffusion-controlled (see Sec. 12.9). 

Partial reduction of polyarenes has been reported. Use of boron trifluoride hydrate (BF3 OH2) as the acid in conjunction with triethylsilane causes the reduction of certain activated aromatic systems 217,262 Thus, treatment of anthracene with a 4-6 molar excess of BE3 OH2 and a 30% molar excess of triethylsilane gives 9,10-dihydroanthracene in 89% yield after 1 hour at room temperature (Eq. 120). Naphthacene gives the analogously reduced product in 88% yield under the same conditions. These conditions also result in the formation of tetralin from 1-hydroxynaphthalene (52%, 4 hours), 2-hydroxy naphthalene (37%, 7 hours), 1-methoxynaphthalene (37%, 10 hours), 2-methoxynaphthalene (26%, 10 hours), and 1-naphthalenethiol (13%, 6 hours). Naphthalene, phenanthrene, 1-methylnaphthalene, 2-naphthalenethiol, phenol, anisole, toluene, and benzene all resist reduction under these conditions.217 Use of deuterated triethylsilane to reduce 1-methoxynaphthalene gives tetralin-l,l,3-yielding information on the mechanism of these reductions.262 2-Mercaptonaphthalenes are reduced to 2,3,4,5-tetrahydronaphthalenes in poor to modest yields.217 263... 

Electron-donor sensitisers such as 1-methoxynaphthalene (forming the Markovnikov addition product) ... 

Illumination of 1-methoxynaphthalene in media containing cyanide ion gives a good yield of l-cyano-4-methoxynaphthalene (and very little 1-cyanonaphthalene) whereas photocyanation of naphthalene itself proceeds with only small yields (Lok and Havinga, 1974). 

Other reagents used for the preparation of lactones from acid anhydrides are lithium borohydride [1019], lithium triethylborohydride (Superhydride ) [1019] and lithium tris sec-butyl)borohydride (L-Selectride ) [1019]. Of the three complex borohydrides the last one is most stereoselective in the reduction of 3-methylphthalic anhydride, 3-methoxyphthalic anhydride, and 1-methoxynaphthalene-2,3-dicarboxylic anhydride. It reduces the less sterically hindered carbonyl group with 85-90% stereoselectivity and is 83-91% yield [1019]. 

Methoxynaphthalenes may be lithiated in their ortho or peri positions according to conditions (see Table 1 in Section LA). 1,4-Dimethoxynaphthalene, for example, perilithi-ates cleanly with f-BuLi (Scheme 67) ... 

AT20 ChHiqO 1-methoxynaphthalene 1-CH3OC10H7 MeCN VY Pr4NC104 0.1 - - - RPE/SCE --- -... 

The latter result is particularly interesting because it contrasts so vividly with the chemistry observed in homogeneous solution. With a homogeneously dispersed single electron photoacceptor, 1-methoxynaphthalene gives the same product as that formed in Ti02, but 1-methylnaphthalene gives a completely different product, that derived from exclusive side chain activation by radical cation deprotonation, eq. 94 (290) ... 

The main products of the photolysis42 of the complex between 1-methoxynaphthalene and tetranitromethane are l-methoxy-4-nitronaphthalene and l-methoxy-4-trinitromethyl-naphthalene. 

To a clean reaction vessel add 1-methoxynaphthalene (3.16 g, 20 mmol), benzoyl chloride (2.8 g, 20 mmol), and Envirocat EPZG (0.50 g), which is dried by distillation with tolune prior to the reaction. 

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