Photo Fries rearrangements of 1-naphthyl esters in the synthesis of 2-acylnaphthoquinones

Abstract

The photo Fries rearrangements of esters of 1-naphthol and 5-methoxy-l-naphthol to the corresponding l-hydroxy-2-acylnaphthalenes have been carried out. The best yield (70%) was obtained by irradiating 5methoxy-l-naphthyl acetate in ethyl acetate. By contrast the yield from 1-naphthyl acetate under similar conditions was 40%. Oxidation of l-hydroxy-5-methoxy-2-naphthyl cyclohexyl ketone with thallium trinitrate gave the corresponding 1,4-quinone. These results provide a method for the regioselective synthesis of tricyclic analogues of adriamycinone.

Photo‐Fries Rearrangement in Polymeric Media: An Investigation on Fully Aromatic Esters Containing the Naphthyl Chromophore

“…The product distribution found for ester 3 may be compared to that of benzoic acid, 1-naphthyl ester. [12] For this compound, Crouse et al reported 47% o-hydroxyketone and 15% 1-naphthol as the main reaction products when irradiation was carried out with an (unfiltered) Hg lamp under nitrogen. Similarly, the 254 nm irradiation of 1-naphthoic acid, 5,8-dihydro-1-naphthyl ester in benzene solution yielded 30% of o-hydroxyketone, 20% of p-hydroxyketone and 30% of free phenol.…”

“…The ''escape products'' of the geminate radical pair are mainly phenols, but also free carboxylic acids and hydrocarbons have been reported to occur as side products. [2] Several researchers [2,[12][13][14] have compared the photoFries reaction of selected compounds in various media, among them organic solvents, [2,12] polyethylene matrix [5,13] and zeolithes. [14] While for some aryl esters (e.g., acetic acid, (5-methoxy)-1-naphthyl ester in ethyl acetate solution) the yield of the ortho-hydroxyketone can be up to 70%, [12] in most cases the yield of the acyl migration products does not exceed 20-30%.…”

“…Over the past years, the photochemistry of acetic acid, 1-naphthyl ester has been studied by several authors. [7,8,12,21] In the case of 1-naphthyl esters, the photochemical yield of hydroxyketones is generally higher than that for phenyl esters. For acetic acid, (5-methoxy)-1-naphthyl ester, the yield of the orthohydroxyketone can be up to 70%.…”

“…For acetic acid, (5-methoxy)-1-naphthyl ester, the yield of the orthohydroxyketone can be up to 70%. [12] As demonstrated by Guillet et al, [16] the quantum yield F of acyl migration products is higher for 1-naphthyl esters than for 2-naphthyl esters: the 1-naphthyl ester of isobutyric acid yields 4-acyl-1-naphthol with F ¼ 0.13 and 2-acyl-1-naphthol with F ¼ 0.07, while the 2-naphthyl ester yields 6-acyl-2-naphthol with F ¼ 0.05 and 1-acylnaphthol with F ¼ 0.006. The same trend is found for the polyacrylates and polymethacrylates of 1-and 2-naphthol in tetrahydrofuran.…”

First synthesis of 2‐(2,4,4‐trimethyl‐3,4‐dihydro‐2H‐benzo[h]chromen‐2‐yl)‐1‐naphthol and 3‐(2,4,4‐trimethyl‐3,4‐dihydro‐2H‐benzo[g]chromen‐2‐yl)‐2‐naphthol from 1‐ and 2‐naphthol derivatives

“…2). Grignard reaction on 2-acetyl-1-naphthol 5 [9] V C 2011 HeteroCorporation þ indicated the formation of pseudomolecular ion of 1.…”