2-Chloroanisole → Tert-butyl 4-(2-methoxyphenyl)piperazine-1-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

RuPhos (32.7 mg, 0.07 mmol) and palladium (II) acetate (15.75 mg, 0.07 mmol) were suspended in toluene (1 mL) at ambient temperature. The mixture was degassed and purged with nitrogen several times and warmed to 50°C for 20 mins. In a separate vessel were mixed 1-chloro-2-methoxybenzene (100 mg, 0.70 mmol), tert-butyl piperazine-1-carboxylate (131 mg, 0.70 mmol), sodium tertbutoxide (101 mg, 1.05 mmol) and toluene (2 mL). The suspension was degassed and purged with nitrogen then warmed to 50°C. The solution of catalyst was added to the reaction vessel and the resulting mixture was degassed and purged with nitrogen. The reaction was heated to 110°C (ext T) under nitrogen for 6 hours then allowed to cool to ambient temperature overnight. The reaction mixture was filtered and concentrated and the crude material purified by flash silica chromatography, elution gradient 20 to 60% EtOAc in heptane. Pure fractions were evaporated to dryness to afford tert-butyl 4-(2-methoxyphenyl)piperazine-1-carboxylate (23.00 mg, 11.22 %) as a colourless dry film. Yield not good....if this route followed maybe try different catalyst - pepsi?

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