Gram-scale synthesis of carboxylic acids via catalytic acceptorless dehydrogenative coupling of alcohols and hydroxides at an ultralow Ru loading

New ruthenium(ii) catalysts enable the synthesis of 2-amino-4H-chromenes using primary alcohols via acceptorless dehydrogenative coupling

“…Based on the control experiments and previous literature reports 28 a plausible mechanism for the Ru( ii ) catalysed synthesis of 2-amino-4 H -chromene has been proposed (Scheme 7). At first, the catalyst reacts with benzyl alcohol with the aid of KOH to give the Ru-alkoxide species ( A ).…”

Cyclometalated C^N diphosphine ruthenium catalysts for Oppenauer-type oxidation/transfer hydrogenation reactions and cytotoxic activity

“…were dissolved in 2.0 mL of methanol and the mixture was stirred at 55 °C for 4 h. The yellow precipitate obtained was filtered, washed with cold methanol (3 mL), diethyl ether (5 mL), n-pentane (2 mL) and dried under reduced pressure. Yield: 60.0 mg (74% 3 J HH = 7.4 Hz, 4 J HH = 1.2 Hz, 2H; Ph), 7.40-7.31 (m, 4H; H5, H8 and Ph), 7.30-7.24 (m, 3H; H3 and Ph), 7.23-7.14 (m, 3H; H11 and Ph), 6.79 (m, 3H; H4, H9 and Ph), 6.57 (td, 3 J HH = 8.7 Hz, 4 J HH = 1.8 Hz, 2H; Ph), 6.55-6.49 (m, 1H; H10), 5.90 (t, 3 J HH = 8.2 Hz, 2H; Ph), 2.98 (pseudo-q, J = 12.0 Hz, 1H; PCH 2 ), 2.69 (tt, J HP = 13.6 Hz, J HH = 3.5 Hz, 1H; PCH 2 ), 2.39-1.79 (m, 5H; PCH 2 CH 2 ), 1.60-1.45 (m, 1H; CH 2 ), 1.22 ppm (s, 3H; CH 3 CO). 13…”

“…(%) for C 39 H 38 N 2 O 2 P 2 Ru (729.76): C 64.19 H 5.25, N 3.84; found: C 64.12, H 5.39, N 3.90. 1 H NMR (400.1 MHz, CD 2 Cl 2 , 298 K): δ = 8.04 (br s, 2H; Ph), 7.88 (td, 3 J HH = 8.5 Hz, 4 J HH = 1.2 Hz, 2H; Ph), 7.56 (br m, 3H; Ph), 7.49-7.41 (m, 3H; H3, H5 and Ph), 7.38 (td, 3 J HH = 7.8 Hz, 4 J HH = 1.6 Hz, 2H; Ph), 7.30-7.25 (m, 3H; H7 and Ph), 7.24-7.17 (m, 2H; Ph), 7.06 (d, 3 J HH = 8.4 Hz, 1H; H10), 6.89 (td, 3 J HH = 7.3 Hz, 4 J HH = 1.2 Hz, 1H; Ph), 6.86-6.77 (m, 2H; H8 and Ph), 6.71 (td, 3 J HH = 7.9 Hz, 3 J HH = 1.8 Hz, 2H; Ph), 6.55-6.47 (m, 1H; H9), 6.11 (br m, 1H; H4), 6.01 (t, 3 J HH = 8.1 Hz, 2H; Ph), 2.98 (pseudo-q, J = 11.9 Hz, 1H; PCH 2 ), 2.57 (tt, J HP = 13.8 Hz, J HH = 3.7 Hz, 1H; PCH 2 ), 2.36-1.74 (m, 5H; PCH 2 CH 2 ), 1.58-1.44 (m, 1H; CH 2 ), 1.27 ppm (s, 3H; CH 3 CO). 13 C{ 1 H} NMR (100.6 MHz, CD 2 Cl 2 , 298…”

“…(%) for C 39 H 39 NO 3 P 2 Ru (732.76): C 63.93, H 5.36, N 1.91; found: C 63.81, H 5.40, N 1.88. 1 H NMR (400.1 MHz, CD 2 Cl 2 , 298 K): δ = 8.04 (br s, 2H; Ph), 7.81 (t, 3 J HH = 8.2 Hz, 2H; Ph), 7.58 (m, 3H; Ph), 7.42 (td,3 J HH = 7.2 Hz,4 J HH = 1.0 Hz, 1H; Ph), 7.34 (td,3 J HH = 7.3 Hz,4 J HH = 1.3 Hz, 2H; Ph), 7.30-7.25 (m, 3H; Ph), 7.22-7.12 (m, 3H; Ph), 7.09 (dd,3 J HH = 7.5 Hz,4 J HH = 1.3 Hz, 1H; H10), 7.03 (d,3 J HH = 7.7 Hz, 1H; H7), 6.98 (t,3 J HH = 7.0 Hz, 2H; Ph), 6.74 (t,3 J HH = 7.2 Hz, 1H; H8), 6.58 (td,3 J HH = 7.5 Hz,4 J HH = 1.4 Hz, 1H; H9), 6.24 (t,3 J HH = 7.9 Hz, 2H; Ph), 4.36 (dt, 1 J HH = 10.2 Hz,3 J HH = 7.8 Hz, CP = 26.3 Hz; PCH 2 ), 26.4 (d, 1 J CP = 32.2 Hz; PCH 2 ), 25.7 (s; CH 2 ), 21.9 ppm (s; CH 2 ). 31 P{ 1 H} NMR (162.0 MHz, CD 2 -Cl 2 , 298 K): δ = 57.7 (d, 2 J PP = 38.1 Hz), 51.6 ppm (d, 2 J PP = 37.2 Hz).…”

Iridium Nanoparticles on NiO as Heterogeneous Catalysts for Acceptorless Dehydrogenation of Primary Alcohols with Tunable Product Selectivity

“…Literature survey reveals that AD reactions of alcohol have been mainly accomplished by homogeneous, ligand-based, precious metal catalysts like Ru − and Ir − or selected nonprecious metal catalysts like Co, , Mn, − Ni, − etc. However, despite these advances, the reported homogeneous catalysts suffer from inherent sustainability issues, like use of expensive ligands, lengthy synthesis and purification procedures of ligands and/or complexes, problems in catalyst recovery, efficient recycling, etc.…”