3-Fluorophenylboronic acid → 6-(3-fluorophenyl)-2'-methyl-2-(tetrahydro-2H-pyran-3-yl)-2'H-spiro[chroman-4,5'-[1,2,4]oxadiazol]-3'-amine

Participants

Reaction Conditions

Reaction Steps

Pd(PPh3)2Cl2 (10 mg) in a 10 mL tube under Ar was treated sequentially with 6-bromo-2′-methyl-2-(tetrahydro-2H-pyran-3-yl)-2′H-spiro[chroman-4,5′-[1,2,4]oxadiazol]-3′-amine (40 mg, 0.1 mmol) in 1,4-dioxane (2 mL), Cs2CO3 (2 N, 0.4 mL) and 3-fluorophenylboronic acid (29.3 mg, 0.2 mmol). The mixture was heated in a microwave reactor at 120° C. for 30 min. The reaction mixture was concentrated in vacuo to give the residue, which was purified by preparative TLC and then by preparative HPLC to give pure product 6-(3-fluorophenyl)-2′-methyl-2-(tetrahydro-2H-pyran-3-yl)-2′H-spiro[chroman-4,5′-[1,2,4]oxadiazol]-3′-amine (5 mg, 10%). 1H-NMR (MeOD): 1.70 (m, 3H), 2.01 (m, 3H), 2.49 (m, 0.5H), 2.71 (m, 1H), 3.32 (d, 3H), 3.43 (m, 1H), 3.53 (m, 1H), 3.91 (dd, 2H), 4.19 (m, 2H), 7.03 (m, 2H), 7.32 (d, 1H), 7.43 (m, 2H), 7.66 (t, 1H), 7.89 (s, 1H).

Provenance & Evidence