Cesium carbonate → 3-(1,4-Dioxa-8-aza-spiro[4.5]dec-8-yl)-4-methyl-benzoic acid methyl ester

Beteiligte Stoffe

Reaktionsschritte

A mixture of 2,2′-Bis(diphenylphosphino)1,1′-binaphthyl[BINAP] (54.35 mg, 0.085 mmol) and Palladium(II)acetate[Pd(OAc)2] (6.95 mg, 0.028 mmol) in dry toluene (3 ml) was stirred vigorously and nitrogen was bubbled through the suspension for 30 minutes. To this, 1,4-Dioxa-8-aza-spiro[4.5]-decane (100 mg, 0.699 mmol), 3-Bromo-4-methyl-benzoic acid methyl ester (192.1 mg, 0.839 mmol) and dry Cesium Carbonate (683.5 mg, 2.09 mmol) was added. Nitrogen was bubbled through for another 30 minutes; the mixture was allowed to reflux overnight. The mixture was cooled, diluted with ethylacetate, water was added and the layers separated. The aqueous layer was extracted with ethyl acetate) and the two organic extracts were combined. The organics were washed with brine, then dried (sodium sulfate), filtered and concentrated. Further purification by silica gel chromatography using 5-10% ethyl acetate/Hexane as eluent provided 3-(1,4-Dioxa-8-aza-spiro[4.5]dec-8-yl)-4-methyl-benzoic acid methyl ester [11] as a yellow solid [150.5 mg, 61.7%]

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