2- methoxynaphthalene benzoylation

An unusually facile hydroxydemethoxylation reaction has been reported for 1-benzoyl-4-methoxynaphthalene. The use of 0-enriched hydroxide confirmed that reaction occurs by the NAr pathway rather than by cleavage of the oxygen to methyl bond. A related reaction is observed in 3-(4-methoxy-l-naphthoyl)indole derivatives. These results indicate the possibility of SnAt activation by a 4-carbonyl group the reaction is facilitated by use of a naphthyl ketone as substrate and DMSO as solvent. ... 

Amorphous and mesostructured Zr02 solid catalysts impregnated with various amounts of triflic acid were tested in the acylation of biphenyl356,357 and toluene358 (with benzoyl chloride and para-toluyl chloride, respectively, nitrobenzene solvent, 170°C and 130°C). All catalysts exhibited lower activity when compared with neat triflic acid. The mesoporous catalysts, however, showed complete selectivity in the formation of para-benzoylbiphenyl. A triflic acid-silica catalyst, in turn, prepared using an aminopropyl-modified silica, showed good characteristics in the solvent-less acetylation of anisole and 2-methoxynaphthalene with acetic anhydride.359,360 The activity of 1,1,2,2-tetrafluoroethanesulfonic acid, either neat or embedded in silica, was found to be similar to that of triflic acid in the acetylation of anisole.196... 

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. 

To mention some examples, benzoylation of xylenes was particularly studied because of the use of dimethylbenzophenones as UV-light stabilizers in plastics. Moreover, 2-acetyl-6-methoxynaphthalene represents the precursor to the antirheumatic Naproxen.i ortho- and para-Hydroxy-acetophenones are widely used for the synthesis of aspirin and paracetamol (4-acetamidophenol), respectively. orf/zo-Hydroxyacetophenone is also a key intermediate in the production of 4-hydroxycoumarin and warfarin, both used as anticoagulant drugs in the therapy of thrombotic diseases, and it is also employed in the synthesis of flavonones. ... 

The benzoylation of 2-methoxynaphthalene (2-MN) 4 with an equimo-lecular amount of BC in the presence of aluminum chloride (5% mol) gives producfs 5, 6, and 7 in 63 25 12 rafio (Table 3.1). With indium trichloride in place of aluminum chloride, compound 5 is obtained in a higher selectivity (88%). On increasing the temperature in the reaction with indium trichloride, the product composition is changed, and compound 6 is the predominant one (84% selectivity). Quite similar results are achieved with iron trichloride, tin tetrachloride, and zinc chloride, while in the case of antimony pentachloride and titanium tetrachloride, compound 5 is the major product. Mechanistic studies show that the reaction involves the isomerization of 5 to 7 and 6. 

MN with BC exclusively produces the kinetic product l-benzoyl-2-meth-oxynaphthalene in 72% yield, which cannot be isomerized in [bmim][Bp4] into the thermod5mamic isomer 6-benzoyl-2-methoxynaphthalene even after prolonged reaction times, reminiscent of the acylation of naphthalene with acetyl chloride (AC) in ionic liquid-catalyst [emimJCl-aluminum... 

It is known that the benzoylation of 2-methoxynaphthalene (4) with an equimolar amount of benzoyl chloride in the presence of aluminum chloride (5% mol) gives products 5,6, and 7 in 51% yield and 63 25 12 ratio (Scheme 3.2) [9]. 

Friedel-Crafts Reactions. Aluminum trifluoromethanesulfonate has been used for the Friedel-Crafts alkylation reaction of toluene with isopropyl and tert-butyl chlorides (eq 1), and for the acylation of benzene and toluene with acetyl and benzoyl chlorides in low to moderate yields. Intramolecular Friedel-Crafts acylation of an aromatic compound with Meldrum s acid has also been reported using catalytic amounts of Al(OTf)3. Acylation of 2-methoxynaphthalene with acetic anhydride has been reported using Al(OTf)3 and lithium perchlorate as an additive to afford the corresponding 6-acetylated adduct in 83% yield. Effective acylation of arenes with carboxylic acids has also been disclosed using polystyrene-supported Al(OTf)3. ... 

Sb(0S02CF3)3 has been reported as Lewis catalyst for reactions requiring traces of water. Benzoylation of toluene, acylation of m-xylene, and sulfonylation of toluene were examples demonstrating its role in Friedel-Crafts reactions [26]. Also, catalytic amount of Sb(OTf)3 catalyzed the reaction of 2-methoxynaphthalene with acetic anhydride in nitromethane-lithium perchlorate to afford 2-acetyl-6-methoxynaphthalene, a well-known intermediate for the synthesis of naproxen, in a high yield [27]. 

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