Furan-3-boronic acid → HCID 57063305, compound

Participants

Reaction Conditions

Reaction Steps

To a suspension of 221 mg (0.40 mmol) of N-[4-(4-bromophenoxy) benzenesulfonyl]--S--[(pyrid-2-yl)methyl]-D-penicillamine (from example 3(d)) in 2 mL of benzene and 2 mL of 2M aqueous Na2CO3 solution was added a solution of 71 mg (0.48 mmol) of 3-furan boronic acid (J. Org. Chem. 1984, 49, 5237-5243) in 2 mL of EtOH. To the resulting mixture was added solid Pd(PPh3)4 (46 mg, 0.04 mmol) under a flow of Ar. The mixture was heated at 80° C. with vigorous stirring for 72 hours, cooled to room temperature, and partitioned between ehtyl acetate and AcOH/H2O buffer (pH 3). The aqueous layer was adjusted to pH of 3 by adding AcOH, then extracted with EtOAc (2×70 mL). The combined organic layers were washed with brine, dried over Na2SO4, and concentrated. The residual yellow solid was chromatographed on silica gel, eluting first with CH2Cl2, then with 10% methanol in dichloromethane to elute the product fractions. After concentration of the product-containing fractions, the residue was triturated with hexane/t-butyl methyl ether, and the solid was collected by filtration. The solid was dried in high vacuum to give 166.1 mg (77%) of N-[4-(4-(furan-3-yl)phenoxy)benzenesulfonyl]--S--[(pyrid-2-yl)methyl]-D-penicillamine as a yellow solid: mp 185-189° C.; 1H--NMR (CDCl3) δ 1.40 (s, 3H) 1.44 (s, 3H), 3.32-4.01 (m, 3H), 6.83 (s, 1H), 7.10-7.13 (m, 4H), 7.22-7.23 (m, 2H), 7.57-7.92 (m, 8H), 8.42 (d, J=4 Hz, 2H).

Provenance & Evidence