The Friedel-Crafts reaction. VI. Further evidence for γ-substitution in resorcinol and orcinol derivatives was written by Desal, R. D.;Vakil, V. M.. And the article was included in Proceedings – Indian Academy of Sciences, Section A in 1940.Formula: C9H10O3 This article mentions the following:
AcCl (20 cc.) was added gradually to a solution of 12 g. anhydrous orcinol and 26 g. anhydrous AlCl3 in 150 cc. PhNO2 and the mixture allowed to stand for 24 h., then heated on the water bath for 2 h., yielding 8 g. γ-orcacetophenone (I), needles, m. 142-4°; oxime, needles, m. 211-12°; p-nitrophenylhydrazone, red microcrystalline plates, m. 245° (in 3 out of 7 experiments a mixture of β-and γ-orcacetophenones was formed instead of only the γ-variety; these were separated by crystallization from C6H6). Clemmensen reduction of I yielded 2-ethyl-5-methylresorcinol, needles, m. 135°. A mixture of 14 g. anhydrous AlCl3, 12 g. orcinol and 17 g. BzCl in 75 cc. PhNO2, after standing overnight, was heated on the water bath for 1 h., yielding after trituration with NaHCO3 solution and crystallization of the residue from C6H6, pale yellow needles of 2,4-dihydroxy-5-methylbenzophenone, m. 138°. Treatment of either β- or γ-orcacetophenone in PhNO2 solution with Ac2O in the presence of anhydrous AlCl3 gave lustrous needles of 2,4-diacetyl-5-methylresorcinol, m. 95°, giving a purple-red color with FeCl3; p-nitrophenylhydrazone, red microcrystalline needles, m. 242°. A mixture of 20 g. resacetophenone, 24 g. BzCl and 18 g. of AlCl3 in 200 cc. PhNO2 was heated on the water bath for 2 h.; after treatment of the product with NaHCO3, solution in 5% NaOH, acidification of the solution and exhaustive extraction of the dry solid with petr. ether, the residue was crystallized from C6H6 and from alc., yielding 0.8 g. of pale yellow lustrous needles of 2-benzoyl-4-acetylresorcinol (II), m. 165°, gives a red color with FeCl3 solution; p-nitrophenylhydrazone, red microcrystalline powder, m. above 300°; the petr. ether solution yielded lustrous plates (from alc.) of 4-O-benzoyl-resacetophenone (III), m. 110° mono-Br derivative, lustrous needles from alc., m. 176°. II could not be brominated at room temperature either in CHCl3 or glacial AcOH; it could not be condensed with Ac2O in presence of anhydrous AlCl3. III (2 g.) heated with 4 g. anhydrous AlCl3 at 140° for 1.5 h. underwent the Fries transformation to give II. BzCl (1.7 g.) was gradually added to 2 g. Me 2,4-dihydroxy-5-acetylbenzoate and 1.6 g. anhydrous AlCl3 in 50 cc. PhNO2 and the mixture heated for 6 h. at 130-40° and allowed to stand overnight, yielding 42% of Me 2,4-dihydroxy-3-benzoyl-5-acetylbenzoate (IV), needles, m. 204°; its alc. solution gives a red color with FeCl3. Saponification of IV with KOH gave the acid (V), needles, m. 217°, whose alc. solution gave a red color with FeCl3. V heated at 220-25° for 1 h. gave pale yellow needles (from alc.) of 2-benzoyl-4-acetylresorcinol, m. 165°. A mixture of 10 g. anhydrous AlCl3, 7 g. 4-benzoylresorcinol, 4 g. Ac2O and 75 cc. PhNO2 was heated 6 h. on the water bath; the product after solution in 5% NaOH solution and precipitation with acid was exhaustively extracted with petr. ether, yielding, (1) upon concentration of the petr. ether solution, 30% of 2-acetyl-4-benzoyl-resorcinol, needles, m. 107-8°, whose alc. solution gave a wine-red color with FeCl3 (p-nitrophenylhydrazone, red microcrystalline powder, m. 227-9°), and (2) after crystallization of the residue from dilute alc., 5% of 2,6-diacetyl-4-benzoyl-resorcinol, m. 151°, whose alc. solution gave a cherry-red color with FeCl3 (p-nitrophenylhydrazone, reddish microcrystalline powder, m. 288-90° (decomposition)). 2-Acetylresorcinol (1 g.), 1 g. AlCl3 and 1.2 g. BzCl in 30 cc. PhNO2 after standing at ordinary temperature was heated 1 h. on the water bath. After treatment with NaHCO3 solution, the residue was extracted with petr. ether; the petr. ether solution upon concentration gave 2-acetyl-4-benzoylresorcinol (VI), needles, m. 108°. Friedel-Crafts condensation of VI with Ac2O yielded 2,6-diacetyl-4-benzoylresorcinol, m. 151°. In the experiment, the researchers used many compounds, for example, 2′,6′-Dihydroxy-4′-methylacetophenone (cas: 1634-34-0Formula: C9H10O3).
2′,6′-Dihydroxy-4′-methylacetophenone (cas: 1634-34-0) belongs to alcohols. Similar to water, an alcohol can be pictured as having an sp3 hybridized tetrahedral oxygen atom with nonbonding pairs of electrons occupying two of the four sp3 hybrid orbitals. A multistep synthesis may use Grignard-like reactions to form an alcohol with the desired carbon structure, followed by reactions to convert the hydroxyl group of the alcohol to the desired functionality.Formula: C9H10O3
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Alcohol – Wikipedia,
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