Naphthoate

Methyl 3-hydroxy-2-naphthoate [883-99-8] M 202.2, m 73-74 , pK ,( -9.0. Crystd from MeOH (charcoal) containing a little water. 

Iwabuchi T, S Harayama (1998b) Biochemical and molecular characterization of l-hydroxy-2-naphthoate dioxygenase from Nocardioides sp. KP7. J. Biol. Chem. 273 8332-8336. 

Morawski B, RW Eaton, JT Rossiter, S Guoping, H Griengl, DW Ribbons (1997) 2-Naphthoate catabolic pathway in Burkholderia strain JT 1500. J Bacterial 179 115-121. 

Althongh the degradation of naphthalene-2-carboxylate by Burkholderia sp. strain JT 1500 involves the formation of 1-hydroxy naphthalene-2-carboxylate, this is not formed from the expected (l/ ,25)-di-l,2-dihydrodiol-2-naphthoate. Possibly, therefore, the reaction is carried out by a monooxygenase, or a dehydration step is involved. Subsequent reactions produced pyruvate and o-phthalate that was degraded via 4,5-dihydroxyphthalate (Morawski et al. 1997). Degradation of naphthalene carboxylates formed by oxidation of methyl groups has already been noted. 

Adachi K, T Iwabuchi, H Sano, S Harayama (1999) Structure of the ring cleavage product of l-hydroxy-2-naphthoate, an intermediate of the phenanthrene-degradative pathway of Nocardioides sp. strain KP7. J Bacterial 181 757-763. 

The synthetic utility of the ring expansion reaction was demonstrated by its application to the synthesis of thermolabile thiepins. When the diazo compound (66) obtained from benzo[c]thiopyrylium salt 65 was treated with palladium catalyst under the same conditions as in the case of 63, the product isolated was ethyl 2-naphthoate (68)48). The plausible reaction pathway is one comprising i) decomposition of 66 to the corresponding carbene intermediate, ii) ring expansion to the... 

This carboxylation reaction is of importance mainly for the manufacture from 2-naphthol of P-oxynaphthoic acid (BON) acid, the parent acid of sodium 3-hydroxy-2-naphthoate (4-35). The carboxylation is achieved by heating the sodium salt of 2-naphthol under pressure in an atmosphere of carbon dioxide (Scheme 4.25). Under these conditions an equilibrium mixture of the naphthol and its carboxylated derivative is established, the mixture containing about 30% of the carboxylic acid. The desired product is extracted from the reaction mixture and the unchanged 2-naphthol is recycled. 

Bephenium Bephenium, 3-hydroxy-2-naphthoat benzyldimethyl(2-phenoxyethyl) ammonia (38.1.37), is made by reacting the sodium salt of 3-hydroxy-2-naphthoic acid with benzyldimethyl(2-phenoxyethyl)ammonia chloride (38.1.36). This is in turn made from benzyl chloride and Af-(2-phenoxyethyl)dimethylamine (38.1.35), which is synthesized by reacting sodium phenolate with 2-dimethylaminoethylchloride [41,42]. 

A. 3,5-Dimethylphenyl 1-bromo-2-naphthoate (3). Under a nitrogen atmosphere, a 250-mL, oven-dried, round-bottomed flask containing anhydrous dichloromethane (100 mL) is charged with 1-bromo-2-naphthoic acid (1, 2.51 g, 10.0 mmol), 3,5-dimethylphenol (2, 1.23 g, 10.1 mmol), dicyclohexylcarbodiimide (DCC, 2.26 g. 11.0 mmol), and 4-(dimethylamino)pyridine (DMAP, 244 mg, 2.00 mmol) (Note 1). After the mixture is stirred for 12 hr at room temperature, the white precipitate that forms (Note 2) is discarded by filtration through a Buchner funnel. From the clear filtrate, the solvent is removed by rotary evaporation (35°C, 720 mbar, 540 mm) to give a colorless solid. RItration through a short silica gel column (5 x 40-cm column, silica gel 0.063 - 0.2 mm, 150 g eluent hexane / diethyl ether 5 1) delivers 3.35 g (94%) of the ester 3, which Is recrystallized from diethyl ether / hexane to give 3.28 g (92%) of a colorless solid (Note 3). 

B. 1,3-Dimethyl-6H-benzo[b]naphtho[1,2-d]pyran-6-one (4). Under an argon atmosphere, a 250-mL, oven-dried, round-bottomed flask, equipped with a reflux condenser, is charged with freshly distilled N,N-dimethylacetamide (DMA, 130 mL), 3,5-dimethylphenyl 1-bromo-2-naphthoate (3, 3.24 g, 9.12 mmol), palladium(ll) acetate (205 mg, 0.913 mmol), triphenylphosphine (481 mg, 1.83 mmol), and sodium acetate (1.50 g, 18.3 mmol) (Notes 4 and 5). The orange suspension is degassed three times, placed in a preheated (130°C) oil bath (Note 5), and stirred at 130°C for 12 hr (Note 6). Removal of the solvent at 40°C (0.1 mbar, 0.075 mm) gives a black oily residue, which is Chromatographed (5 x 40 cm column, silica gel 0.063 - 0.2 mm, 170 g, 1 cm of charcoal at the top of the column eluent hexane / diethyl ether 5 1), to yield 2.00 g (80%) of the lactone 4 as a slightly yellow solid. Recrystallization from diethyl ether / hexane delivers 1.63 g (65%) of colorless or pale yellow crystals (Note 7). 

With the bisoxazoline hgand (S)-Phbox and CuCl, the asymmetric oxidative couphng of 2-naphthol and hydroxy-2-naphthoates resulted in an asymmetrically substituted 2,2 -binaphthol with ee s of up to 65% [260]. On the basis of the previous results obtained with this catalyst system, the asymmetric oxidative cross-coupling polymerization of 2,3-dihydroxynaphthalene [261] and methyl 6,6 -dihydroxy-2,2 -binaphthalene-7,7 -dicarboxylate [262] as well as the copolymerization of 6,6 -dihydroxy-2,2 -binaphthalene and dihexyl 6,6 -dihydroxy-2,2 -binaphthalene-7,7 -dicarboxylate with Cu diamine catalysts were carried out imder aerobic conditions, using O2 as the oxidant, and a cross-coupling selectivity of 99% was achieved [263]. 

The starting materials required for preparing the 2,3-disubstituted tetrahydronaphthalenes were 5,6,7,8-tetrahydro-2-naphthol (obtainable from tetrahydronaphthalene) and methyl 3-hydroxy-2-naphthoate, which was reduced to the known tetrahydro ester (Vc) and the latter saponified to the known tetrahydroacid. 

Methyl 4 Chloro-3-wMkoxy-5,6,7y8-tetrahydro-2-naphthoate> prepared in 52% yield by useTof diazomethane [18], was recrystallized four times from petroleum ether (b.p, 30-65°) m.p. 43 6-46°. 

Methyl 3-methoxy-596 7,8-tetrahydro-2-naphthoate—To 300 ml of potassium hypochlorite solution [12] (ca. 0 46 mole of hypochlorite) at 11° was added, with stirring, 2 0 g (0 0098 mole) of 3-methoxy-5,6,7,8-tetrahydro- 2 acetonaphthone in 60 ml of methanol. The mixture was stirred for 5 hours at 11-30°. Filtration separated 0 92 g of yellow... 

B. Ethyl l,3-dihydroxy-2-naphthoate. In a 1-1. flask 1 volume (87 ml.) of the crude ester is added in one lot to 3 volumes (261 ml.) of concentrated sulfuric acid without cooling, and the solution is allowed to stand for about 1 week (Note 4). The whole mixture, including any precipitate which may have formed, is poured slowly with stirring into a mixture of 1 kg. of icc and 500 ml. of water (Note 5) the solid yellow ester is filtered with suction, washed with a small amount of cold water, pressed in the filter for 30 minutes with a rubber dam, and finally dried in a vacuum desiccator. The yield of ester melting at 80° is 58-68 g. (50-59%, based on the malonic ester used). 

The yield of ethyl l,3-dihydroxy-2-naphthoate is decreased to 45% if the sulfuric acid solution is allowed to stand for only 2 days. 

Scheme 3 Synthesis of Methyl (R5)-8-[(teM-Butoxycarbonylamino)methyl]-5,6,7,8-tetrahydro-2-naphthoate 391...

---