Mild Conversion of β‐Diketones and β‐Ketoesters to Carboxylic Acids.

Abstract

2006 Carboxylic acids P 0250 Mild Conversion of β-Diketones and β-Ketoesters to Carboxylic Acids. -In the presence of CAN α-unsubstituted β-diketones and β-ketoesters efficiently and rapidly undergo oxidation to carboxylic acids. -(ZHANG, Y.; JIAO, J.; FLOWERS*, R. A. I.; J. Org. Chem. 71 (2006) 12, 4516-4520; Dep. Chem., Lehigh Univ., Bethlehem, PA 18015, USA; Eng.) -Jannicke 41-054

Structure−Antifungal Activity Relationship of Cinnamic Acid Derivatives

“…The residue was subjected to column chromatography on Si gel with mixtures of n -hexane−EtOAc (7:3) as eluent to yield 85 mg (84%) of 20 . 1 H NMR and 13 C NMR data were in accordance with literature .…”

“…Biotransformation of 14. Organic extracts were pooled and purified by preparative TLC using EtOAc as eluent, yielding 2-(2-hydroxypropan-2-yl)-2,3-dihydrobenzofuran-5-carboxylic acid (23) as pale yellow crystals: mp 156-158 °C; 1 H NMR (CDCl3) δ 1.25 (s, 3, CH3), 1.37 (s, 3, CH 3), 3.20 (d, 2, J ) 8.5 Hz, H-2), 3.60 (br s, 1, OH), 4.70 (t, 1, J ) 8.5 Hz, H-1), 6.82 (d, 1, J ) 7.4 Hz, H-7), 7.90 (d, 1, J ) 1.5 Hz, H-4), and 7.92 (dd, 1, J ) 7.4 Hz, J ) 1.7 Hz, H-6); 13 C NMR (CDCl3) δ 23.79 (CH 3), 25.83 (CH3), 29.74 (C-3), 71.56 (COH(CH3)2), 90.31 (C-2), 108.77 (C-7), 123.72 (C-9), 127.11 (C-4), 127.56 (C-5), 131.66 (C-6), 165.56 (C-8), and 166.65 (COOH); MS [m/z (%)] 222 (47, M), 204 (37), 189 (37), 164 (100), 119 (60), and 91 (36). These data were in agreement with those reported for anodendroic acid (27).…”