Base-Promoted, Aerobic, and Regioselective Carbon–Hydrogen Bond Activation of Thiophene with Group 9 Metalloporphyrins

Abstract

List of Contents 1. Reaction Conditions Optimization (S2) 2. X-ray Crystallographic Data and Structure of Rh(ttp)(2-thienyl) (3b) (S3) 3. Titration Experiments (S5) 4. NMR Spectra (S11) S2 Reaction Conditions OptimizationThe general procedures described in the experimental section were followed in the optimization reactions.(1) The reaction of Co II (ttp) with thiophene:Co II (ttp) (1a; 11.3 mg, 0.0155 mmol) were added to thiophene (1000 µL, 12.5 mmol). The mixture was heated at 120 o C under air for 2 days. 1a was quantitatively recovered.Co II (ttp) (1a; 11.3 mg, 0.0155 mmol) were added to thiophene (1000 µL, 12.5 mmol). The mixture was degassed for three freeze-pump-thaw cycles, then filled with N 2 . It was then heated at 120 o C under N 2 for 4 days. Co(ttp)(2-thienyl) (3a) was obtained in trace yield with 83% recovery of 1a.Co II (ttp) (1a; 11.3 mg, 0.0155 mmol), KOH (8.7 mg, 0.155 mmol) were added to thiophene (1000 µL, 12.5 mmol). The mixture was heated at 140 o C under air for 6 days. Co(ttp)(2-thienyl) (3a) was obtained in 20% yield with 60% recovery of 1a.Co II (ttp) (1a; 11.3 mg, 0.0155 mmol), KOH (8.7 mg, 0.155 mmol) and H 2 O (28 µL, 1.55 mmol) were added to thiophene (1000 µL, 12.5 mmol). The mixture was heated at 140 o C under air for 8 days. 1a was quantitatively recovered.(2) The reaction of Rh III (ttp)Cl with thiophene:Temperature effects: Rh(ttp)Cl (1b; 11.0 mg, 0.0136 mmol), aqueous KOH (5.5 M, 24.5 µL, 0.135 mmol) were added to thiophene (1000 µL, 12.5 mmol). The mixture was heated at under air. Isolated yields of Rh(ttp)(2-thienyl) (3b) for the reaction at 180 o C for 6 h: 47%; at 200 o C for 2 h: 87%. Yields of Rh(ttp)(3-thienyl) (3c) for the reaction at 180 o C for 6 h: 4; at 200 o C for 2 h: 9%.Atmosphere effects: Rh(ttp)Cl (1b; 11.0 mg, 0.0136 mmol), aqueous KOH (5.5 M, 24.5 µL, 0.135 mmol) were added to thiophene (1000 µL, 12.5 mmol). For the reaction conducted under N 2 , the mixture was degassed for three freeze-pump-thaw cycles, then filled with N 2 .The mixture was heated at 200 o C. Rh(ttp)(2-thienyl) (3b) was obtained in 25% yield under N 2 for 4 h, and 87% yield under air. KOH loading effects: Rh(ttp)Cl (1b; 11.0 mg, 0.0136 mmol), aqueous KOH (n equiv) were added to thiophene (1000 µL, 12.5 mmol). The mixture was heated at 200 o C.