Potassium Phosphate, Tribasic → HCID 54539407, compound

Participants

Reaction Steps

To a stirred suspension of anhydrous Pb(NO3)2 (45.0 g, 138.7 mmol) and anhydrous K3PO4 (75.0 g, 353.3 mmol) in dry acetonitrile (300.0 mL) was added sequentially L-aspartic acid dimethyl ester hydrochloride of Example 1 (32.0 , 161.9 mmol) and 9-bromo-9-phenylfluorene (62.0 g, 193.2 mmol). The mixture which resulted was stirred for 20 h at room temperature and then filtered through celite. The filter cake was washed with chloroform (3×300.0 mL). The combined organic solvents were removed under reduced pressure and the residue oil was partitioned between ether (800.0 mL) and the solution of citric acid (5%, 200.0 mL). The ether layer was removed and the aqueous phase extracted with ether (3×200.0 mL). The combined organic layers were washed with brine (2×150.0 mL), dried (MgSO4) and then removed under reduced pressure. The residue was purified by a flash chromatograph (600.0 g silica gel, EtOAc/hexane, 1/10 to 1/4 ) to provide the product as a pale yellow oil (64.0 g).

Provenance & Evidence