1,4-Dihydro-2-methylbenzoic acid → 2-Methylbenzoic acid

To a suspension of 2-methyl-l,4-dihydrobenzoic acid (0.085 g, 0.50 mmol; 81% pure, from Aldrich Chemical Company) in decalin (5 mL) under a nitrogen atmosphere was added the polysiloxane matrix material containing a homogeneous dispersion of metal particles (0.100 g as prepared according to Example 1). The solution was heated to reflux for 19 hours. On cooling the reaction mixture was diluted with hexane (25 mL) and extracted with aqueous sodium hydroxide (5%) solution (2×5 mL). The basic aqueous solution was acidified and extracted with chloroform (3×4 mL). The combined organic layer was dried over anhydrous sodium sulfate. Removal of solvent on rotary evaporator gave 2-methylbenzoic acid (0.065 g. 96%). IR(KBr) 3600-2000 (br), 2923, 1694, 1300, 920,731 cm-1. 1H NMR (300 MHz, CDCl3) δ 8.03 (ddd, J=8.5, 3.0, 1.5 Hz, 1 H), 7.42 (td, J=8.5, 1.5 Hz, 1H), 7.26 (td, J=8.5, 1.5 Hz, 1 H), 7.22 (dd, J=8.5, 1.5 Hz, 1 H), 2.64 (s, 3H).

1. additioncontaining
2. customa homogeneous dispersion of metal particles (0.100 g as prepared according to Example 1)
3. temperatureThe solution was heated
4. temperatureto reflux for 19 hours
5. temperatureOn cooling the reaction mixture
6. extractionextracted with aqueous sodium hydroxide (5%) solution (2×5 mL)
7. extractionextracted with chloroform (3×4 mL)
8. dry with materialThe combined organic layer was dried over anhydrous sodium sulfate
9. customRemoval of solvent
10. customon rotary evaporator

ORD record

ord-3b8aca4417cf4ada848e3468cba3041f

Source dataset

uspto-grants-1996_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05492964