US EPA

7469656 

Journal Article 

A novel synthetic route to 2-arylalkanoic acids by a ruthenium-catalyzed chemoselective oxidation of furan rings 

Noji, M; Sunahara, H; Tsuchiya, KI; Mukai, T; Komasaka, A; Ishii, K 

2008 

1 

Synthesis
ISSN: 0039-7881
EISSN: 1437-210X 

GEORG THIEME VERLAG KG 

STUTTGART 

23 

3835-3845 

English 

10.1055/s-0028-1083222 

WOS:000261944900020 

An efficient two-step synthesis of 2-arylalkanoic acids from 1-arylalkanols is described. Firstly, 1-arylalkylfuran derivatives were synthesized in high yields by the metal triflate catalyzed Friedel-Crafts alkylation of 2-methylfuran with 1-arylalkanols without employing anhydrous conditions. The chemoselective oxidation of the furan ring in 1-arylalkylfurans to carboxylic acid was then investigated. In a solvent system of hexane-EtOAc/H2O (1:3:4), the furan ring was selectively oxidized with 7 equivalents of NaIO 4 by using 0.5 mol% RuCl3 as catalyst to give 2-arylalkanoic acids in good yields. The selectivity of ruthenium oxidation was controlled by the solvent ratio of hexane-EtOAc. © Georg Thieme Verlag Stuttgart. 

1-arylalkylfurans; Carboxylic acids; Chemoselective oxidation; Friedel-Crafts alkylation; Ruthenium tetroxide; Alkylation; Carboxylic acids; Chemical oxygen demand; Chemical reactions; Hexane; Hydrocarbons; Ionic liquids; Isomers; Organic acids; Oxidation; Ruthenium; Ruthenium compounds; Solvents; Sugar (sucrose); 1-arylalkylfurans; Anhydrous conditions; Chemoselective oxidation; Chemoselective oxidations; Friedel-Crafts alkylation; Friedel-Crafts alkylations; Furan rings; Good yields; High yields; Solvent systems; Synthesis of; Synthetic routes; Triflate; Acids; 1 (ferrocenyl)ethanol; 2 (1 ferrocenyl)ethyl 5 methylfuran; 2 (ferrocenyl)methyl 5 methylfuran; 2 [1 (4 benzyloxyphenyl)ethyl] 5 methylfuran; 2 [1 (4 biphenylyl)ethyl] 5 methylfuran; 2 [1 (4 chlorophenyl)ethyl] 5 methylfuran; 2 [1 (4 methoxyphenyl)ethyl] 5 methylfuran; 2 diphenylmethyl 5 methylfuran; 2 methyl 5 (1 phenylcycylohexyl)furan; 2 methyl 5 (2 phenyl 2 propyl)furan; 2 methyl 5 [1 (1 naphthyl)ethyl]furan; 2 methyl 5 [1 (4 methylphenyl)ethyl]furan; 3 [1 (4 chlorophenyl)ethyl] 5 methylfuran; alkanol; arylaliphatic carboxylic acid; benzyl 4 (1 hydroxyethyl)phenylcarbamate; benzyl n [4 [1 (5 methyl 2 furyl)ethyl]phenyl]carbamate; furan derivative; ruthenium; ruthenium derivative; solvent; unclassified drug; water; article; catalyst; Friedel Crafts reaction; oxidation; synthesis