Synthesis
The general procedure for the synthesis of p-methoxycyclohexanone from p-hydroxyanisole is as follows: 7 g of palladium-carbon catalyst and 1 g of borax were added to an autoclave, followed by 150 g of methylcyclohexane and 100 g of p-hydroxyanisole. The reaction was slowly heated to 100 °C and hydrogen was introduced into the system until the pressure reached 1.0 MPa, and stirring was started. When the pressure dropped to 0.5 MPa, hydrogen was supplemented to 1.0 MPa, keeping the reaction pressure in the range of 0.7-1.0 MPa. Continuously monitor the hydrogen consumption, and after the hydrogen consumption stops for a period of time, take samples for reaction process monitoring. When the remaining amount of raw material is less than 1%, the reaction is judged to be complete. The reaction mixture was cooled to 30°C and filtered to remove the catalyst. The filtrate was evaporated to remove the solvent and subsequently distilled under reduced pressure to give 92 g of p-methoxycyclohexanone in 90% yield.
References
[1] Patent: CN107827881, 2018, A. Location in patent: Paragraph 0034; 0035
[2] Patent: US5886232, 1999, A
[3] Tetrahedron Letters, 1994, vol. 35, # 39, p. 7151 - 7154
[4] Journal of Organic Chemistry, 1961, vol. 26, p. 2633 - 2640
[5] Tetrahedron, 1976, vol. 32, p. 2589 - 2594