Cesium carbonate → HCID 58292807, compound

Participants

Reaction Conditions

Reaction Steps

A suspension of (4-benzyloxy-1,6-dihydroxy-1,3-dihydro-benzo[c][1,2]oxaborol-3-yl)-acetic acid ethyl ester (710 mg, 2.08 mmol) and Cs2CO3 (1.36 g, 4.16 mmol) in DMF (10 mL) was treated with 2-chloropyrazine (357 mg, 3.11 mmol) at room temperature and the reaction was heated to 80° C. for 3 h. The reaction mixture was concentrated to dryness. The residue was diluted with water and adjusted pH to 3 by 1N HCl. The aqueous phase was extracted with ethyl acetate. The organic phase was separated, dried (Na2SO4), and concentrated. The residue was purified by preparative HPLC to afford the title compound (410 mg, 50%). MS calcd for (C22H21BN2O6+H)+: 421.2. MS found: (M+H)+=421.2.

Provenance & Evidence