Compound 3ai

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Compound data: 1H NMR

Compound data: 13C NMR

Synthetic procedure: See article for the definitive version of this procedure and for full experimental details.

To a 8.0 mL vial charged with a stir bar, 0.2 mmol of 1ai was dissolved in 2.0 mL dry CH₃CN, Et₃N (80.9 mg, 0.8 mmol) was added. chlorodiisopropylphosphine (64.1 mg, 0.42 mmol) was then added dropwise at room temperature. After the addition of chlorodiisopropylphosphine_, the vial was sealed and heated to 70 ^oC overnight. After the reaction was completed, the solvent was removed under vacuum to give a residue which was washed by benzene (3 x 2 mL). The combined benzene was concentrated under vacuum to give the phosphinite which was used directly for the next step without further purification. To a 35 mL Q-tube charged with a stir bar, the phosphinite from the previous step, [Rh(C₂H₄)₂Cl]₂ (1.94 mg, 0.005 mmol) and 4.0 mL 1,4-dioxane were added. The mixture was freeze-pump-thawed for 3 times and filled with 100 psi H₂ followed by heating to 150 ^oC for 36 h. After the reaction was completed, the H₂ pressure was released and the solvent was removed under vacuum. ~ 2 mL of dichloromethane and ~ 200 mg of silica gel were then added and concentrated to give the silica gel containing the crude product which was further purified by silica gel chromatography (hexane/acetone = 2/1) to give phenol 3ai. White solid (91.6 mg, 69% yield). m.p. 195-197 ^oC. ¹H NMR (500 MHz, CDCl₃) δ 8.8 (s, 1H), 6.63 (d, J = 8.0 Hz, 1H), 6.51 (d, J = 8.0 Hz, 1H), 3.64 (t, J = 7.0 Hz, 2H), 3.26 – 3.10 (m, 2H), 2.29 (s, 3H), 1.98 – 1.96 (m, 2H), 1.92 – 1.87 (m, 2H). ¹³C NMR (126 MHz, CDCl₃) δ 171.1, 154.6, 135.2, 130.2, 124.2, 116.5, 99.9, 48.7, 45.8, 25.8, 24.6, 21.7. HRMS-APCI: [M+H]⁺ Calculated for C₁₂H₁₅INO₂⁺ 332.0142, Found: 332.0140. IR (film, cm^-1) 3137, 2973, 2878, 1607, 1584, 1447, 1393, 1339, 1280, 1129.