Cesium carbonate → 5-(9H-Fluoren-2-yl)-hexahydropyrrolo[3,4-c]pyrrole-2-carboxylic acid tert-butyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A mixture of 3-Boc-3,7-diazabicyclo[3.3.0]octane (340 mg, 1.6 mmol; see WO 0181347), 2-bromofluorene (0.47 g, 1.9 mmol), tris(dibenzylideneacetone)dipalladium (0) (Pd2(dba)3; 44 mg, 0.048 mmol; Strem), racemic-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (BINAP; 50 mg, 0.080 mmol; Strem) and Cs2CO3 (1.0 g, 3.2 mmol; Aldrich) in toluene (25 mL) in a sealed tube was warmed to 85° C. and stirred for 18 h. The material was cooled to ambient temperature, filtered, concentrated under reduced pressure and purified by flash chromatography (silica gel, 50% gradient of EtOAc in hexanes) to afford the title compound (350 mg, 0.93 mmol; 58% yield): MS (DCI/NH3) m/z 377 (M+H)+.

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