3-Isopropylbenzeneboronic acid → 6-(3-isopropylphenyl)-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 (5 mg) in a 10 mL flask under Ar was treated sequentially with the 6-bromo-2′-methyl-2-(tetrahydro-2H-pyran-3-yl)-2′H-spiro[chroman-4,5′-[1,2,4]oxadiazol]-3′-amine (40 mg, 0.105 mmol) in 1,4-dioxane (1 mL), Cs2CO3 (2 N, 0.2 mL) and 3-isopropylphenylboronic acid (25.8 mg, 144 mmol). The mixture was heated at 120° C. under Ar in a microwave reactor for 30 minutes. The reaction mixture was concentrated in vacuo to give the residue, which was purified by preparative TLC and preparative HPLC to give 6-(3-isopropylphenyl)-2′-methyl-2-(tetrahydro-2H-pyran-3-yl)-2′H-spiro[chroman-4,5′-[1,2,4]oxadiazol]-3′-amine (7.5 mg, 18%). 1H NMR (MeOD): 1.31 (d, 6H), 1.68 (m, 2H), 1.92-2.07 (m, 3H), 2.43-2.72 (m, 1H), 2.96 (m, 1H), 3.34 (s, 3H), 3.45-3.58 (m, 2H), 3.83-4.01 (m, 2H), 4.12-4.23 (m, 2H), 6.98 (m, 1H), 7.21 (m, 1H), 7.38 (m, 3H), 7.63 (m, 1H), 7.79 (m, 1H).

Provenance & Evidence