General procedure: The hydrogenation reaction is carried out in a 25 mL stainless steel autoclave with a PTFE liner. Typical operation is as follows: 20 mg of catalyst and 61 mg (0.5 mmol) of p-toluic acid are dispersed homogeneously in 5 mL of deionized water. After sealing the autoclave, the air in the autoclave was replaced with hydrogen and pressurized to 2.5 MPa. The reaction system was heated to 110 °C under magnetic stirring (1000 rpm) and maintained until the reaction was completed. At the end of the reaction, the mixture was extracted using ethyl acetate and the solid catalyst was removed by centrifugation. The recovered solid catalyst was washed sequentially with ethyl acetate, ethanol and deionized water. The filtrate was analyzed by gas chromatography (GC, HP5890, USA) equipped with a 30 m HP-5 capillary column and a flame ionization detector (FID). All products were subjected to structural confirmation by gas chromatography-mass spectrometry (GC-MS, Agilent 6890).
[1] Tetrahedron Letters, 2004, vol. 45, # 35, p. 6669 - 6672
[2] Steroids, 1983, vol. 41, # 3, p. 349 - 359
[3] Recueil des Travaux Chimiques des Pays-Bas, 1961, vol. 80, p. 595 - 607
[4] Journal of the Chemical Society, 1937, p. 2003,2007
