I believe that CTH is a viable route for the conversion of methylone to MDMA. I have searched around on this site and haven't found anything.
The main concern is not opening the methylenedioxy bridge but still providing conditions sufficient to reduce the hydroxyl after reduction of the ketone. When reducing the imine of MDMA via Pd(0)/potassium formate, an ice bath was required for the solution to not become darkened (nasty byproducts). Lewis acids such as FeCl3 or AlCl3 tend to promote the reaction but could this spell doom for the ether linkages?
Considering that a valuable paper I posted on CTH hydrogenolysis of aromatic halides discovered an optimum reaction rate using a ratio of 3:1 -water to formate- for Pd coordination during this type of CTH, I would expect this to hold true for other Pd(0) CTH reactions. Potassium formate with a little AlCl3 or FeCl3, an appropriate water to formate ratio, and a cold reaction with patience for the cessation of evolution of CO2 would be my bet.
If anyone could help out with the paper below, this may shed some light on the potential for this conversion.
Catalytic transfer reduction of carbonyl compounds
Gottfried Brieger and Tzuu-Heng Fu
J. Chem. Soc., Chem. Commun., 1976, 757a-757a
DOI: 10.1039/C3976000757A
Abstract: Aromatic aldehydes and ketones can be reduced to the corresponding hydrocarbons in good yield by catalytic transfer reduction using cyclohexene or limonene as donor, palladium–carbon as catalyst, and a Lewis acid promotor such as ferric chloride.
The main concern is not opening the methylenedioxy bridge but still providing conditions sufficient to reduce the hydroxyl after reduction of the ketone. When reducing the imine of MDMA via Pd(0)/potassium formate, an ice bath was required for the solution to not become darkened (nasty byproducts). Lewis acids such as FeCl3 or AlCl3 tend to promote the reaction but could this spell doom for the ether linkages?
Considering that a valuable paper I posted on CTH hydrogenolysis of aromatic halides discovered an optimum reaction rate using a ratio of 3:1 -water to formate- for Pd coordination during this type of CTH, I would expect this to hold true for other Pd(0) CTH reactions. Potassium formate with a little AlCl3 or FeCl3, an appropriate water to formate ratio, and a cold reaction with patience for the cessation of evolution of CO2 would be my bet.
If anyone could help out with the paper below, this may shed some light on the potential for this conversion.
Catalytic transfer reduction of carbonyl compounds
Gottfried Brieger and Tzuu-Heng Fu
J. Chem. Soc., Chem. Commun., 1976, 757a-757a
DOI: 10.1039/C3976000757A
Abstract: Aromatic aldehydes and ketones can be reduced to the corresponding hydrocarbons in good yield by catalytic transfer reduction using cyclohexene or limonene as donor, palladium–carbon as catalyst, and a Lewis acid promotor such as ferric chloride.
Catalytic transfer reduction of carbonyl compounds_cropped.pdf
