Ethyl Acetate → HCID 89955560, compound

Participants

Reaction Conditions

Reaction Steps

To a cooled (0° C.), clear yellow orange solution of 135D (4.83 g, 9.08 mmol) in ethyl acetate (91 ml) was added Intermediate 10 (1.0 g, 9.99 mmol) and Hunig's base (6.34 ml, 36.3 mmol). Next, 1-propanephosphonic acid cyclic anhydride (T3P) (50% in EtOAc) (13.38 ml, 22.70 mmol) was added dropwise over 20 min and the reaction was stirred at 0° C. After 3 h, the reaction was diluted with EtOAc and washed with sat. NaHCO3. The aqueous layer was extracted with EtOAc (2×). The organic layers were combined and washed with brine, dried over sodium sulfate, filtered and concentrated to give an orange foam. Purification by normal phase chromatography gave 135E (4.53 g, 81% yield) as a white foam. Proton NMR indicated a 3:1 mixture of diastereomers. MS (ESI) m/z: 614.4 (M+H)±.

Provenance & Evidence