Uses
4-Methyl-2,3-dihydro-1H-inden-1-one acts as a reagent in the synthesis of the following organic compounds: 3,6-dimethylcholanthrene, 3,6-dimethyl-7-methoxycholanthrene and 3-methyl-7-methoxycholanthrene.
Synthesis
General procedure for the synthesis of 4-methyl-2,3-dihydro-1H-inden-1-one from 3-(2-methylphenyl)propionic acid: trifluoromethanesulfonic acid (3 equiv.) was slowly added to a solution of 3-(2-methylphenyl)propionic acid (0.5 mmol) dissolved in anhydrous dichloromethane (1.0 mL) in a 12 mL Q-tube?pressure tube at 0 °C (provided by QLabtech). The reaction system was then warmed to room temperature. A PTFE septum was placed on top of the reaction tube and sealed using the appropriate cap and pressure adapter. The sealed reaction tube was heated in an oil bath at 80°C. The progress of the reaction was monitored by thin layer chromatography (TLC) and gas chromatography-mass spectrometry (GC/MS) until the feedstock was completely consumed. Upon completion of the reaction, the mixture was poured into ice water and extracted three times with dichloromethane. The organic phases were combined, dried with anhydrous sodium sulfate, filtered and concentrated under reduced pressure. Finally, the target compound 4-methyl-2,3-dihydro-1H-inden-1-one was purified from the crude product by fast column chromatography.
References
[1] Molecules, 2014, vol. 19, # 5, p. 5599 - 5610
[2] Patent: WO2013/74892, 2013, A1. Location in patent: Page/Page column 39-40
[3] Patent: US9125407, 2015, B2. Location in patent: Page/Page column 27; 28
[4] Chemistry - A European Journal, 2017, vol. 23, # 53, p. 13037 - 13041
[5] Phosphorus, Sulfur and Silicon and the Related Elements, 1994, vol. 91, # 1-4, p. 69 - 80
