2-[tert-butyl(dimethyl)silyl]oxyacetic acid

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 4-[4-(5-{2-[(methylsulphonyl)oxy]phenyl}-4,5-dihydro-1,2-oxazol-3-yl)-1,3-thiazol-2-yl]piperidinium chloride (500 mg) in dimethylformamide (6 ml) under argon were added {[tert-butyl(dimethyl)silyl]oxy}acetic acid (225 mg), diisopropylethylamine (582 mg) and 0-(benzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium tetrafluoroborate (TBTU, 542 mg). The reaction mixture was stirred at room temperature for 18 hours. Then ice-cold sodium hydrogencarbonate solution was added thereto, the mixture was filtered, and the aqueous phase was removed and extracted with ethyl acetate. The combined organic phases were dried over magnesium sulphate and concentrated. Purification by column chromatography gave 2-(3-{2-[1-({[tert-butyl(dimethyl)silyl]oxy}acetyl)piperidin-4-yl]-1,3-thiazol-4-yl}-4,5-dihydro-1,2-oxazol-5-yl)phenyl methanesulphonate (150 mg, 22%). Then ice-cold sodium hydrogencarbonate solution was added the mixture was filtered the aqueous phase was removed extracted with ethyl acetate The combined organic phases were dried over magnesium sulphate concentrated Purification by column chromatography

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 4-[4-(5-{2-[(methylsulphonyl)oxy]phenyl}-4,5-dihydro-1,2-oxazol-3-yl)-1,3-thiazol-2-yl]piperidinium chloride (500 mg) in dimethylformamide (6 ml) under argon were added {[tert-butyl(dimethyl)silyl]oxy}acetic acid (225 mg), diisopropylethylamine (582 mg) and 0-(benzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium tetrafluoroborate (TBTU, 542 mg). The reaction mixture was stirred at room temperature for 18 hours. Then ice-cold sodium hydrogencarbonate solution was added thereto, the mixture was filtered, and the aqueous phase was removed and extracted with ethyl acetate. The combined organic phases were dried over magnesium sulphate and concentrated. Purification by column chromatography gave 2-(3-{2-[1-({[tert-butyl(dimethyl)silyl]oxy}acetyl)piperidin-4-yl]-1,3-thiazol-4-yl}-4,5-dihydro-1,2-oxazol-5-yl)phenyl methanesulphonate (150 mg, 22%). Then ice-cold sodium hydrogencarbonate solution was added the mixture was filtered the aqueous phase was removed extracted with ethyl acetate The combined organic phases were dried over magnesium sulphate concentrated Purification by column chromatography

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of cannabidiol (125.8 mg, 0.4 mmol) and (t-butyldimethylsilyloxy)acetic acid (112.9 mg, 0.51 mmol) in dry dichloromethane (1 mL) was added of 4-dimethylaminopyridine (6.2 mg, 0.03 mmol) followed by N,N′-dicyclohexylcarbodiimide (123.8 mg, 0.6 mmol). The mixture was stirred at ambient temperature for 1 h. Additional amounts of the acid (26.6 mg) and N,N′-dicyclohexylcarbodiimide (31 mg) were added and stirring was continued for 1 h. Mixture was diluted with hexane (2 mL), filtered, and concentrated. The crude product was purified by preparative reverse phase HPLC (C8 column) with acetonitrile-water to afford cannabidiol (t-butyldimethylsilyloxy)acetate as an oil. stirring was continued for 1 h filtered concentrated The crude product was purified by preparative reverse phase HPLC (C8 column) with acetonitrile-water