BIFUNCTIONAL TRANSITION METAL BASED MOLECULAR CATALYSTS HCO 2 H - PowerPoint PPT Presentation

BIFUNCTIONAL TRANSITION METAL － BASED MOLECULAR CATALYSTS HCO 2 H or (CH 3 ) 2 CHOH base M M M X Cl X H X N H N N OH O H H H H R R' R R' 18e amine complex 16e amido complex 18e amine complex X = N, O, P, S M = Ru, Rh, Ir This work Tethered complex Ts (CH 3 ) 3 Si Ph N R n Ru Ru Rh N N Cl N Cl Ph Cl H H H H H H Cl Cl n = 1,2 Ts = p- CH 3 C 6 H 4 SO 2 Ph = C 6 H 5 Symp. Organomet. Chem. Jpn. J. Org. Chem. 1999, 64 , 2186 2004, 51 , PA210

SYNTHESIS OF Rh DIMER BEARING AMINOALKYL SIDE CHAIN Isomerization of the cyclic amine NH 2 NH 3 Cl NH 3 Cl NH 3 Cl HCl in ether (1.5 equiv) + + CH 3 OH 50 °C, 2 h 78% yield Leusen, D.; Beetstra, D. J.; Hessen, B.; Teuben, J. H. Organometallics 2000 , 19 , 4084 NH 3 Cl ClH 3 N Cl Cl RhCl 3 ・ 3H 2 O ＋ Rh Rh CH 3 OH Cl Cl reflux, 66 h NH 3 Cl 1 : 3 Orange powder 83% yield 1 H NMR (DMSO-d 6 ) 13 C NMR (DMSO-d 6 ) δ 7.87 (br, 3H, N H 3 ) δ 102.1, 98.6, 93.3 2.92 (br, 2H, C H 2 NH 3 ) (each d, C 5 Me 4 ) 2.41 (t, 2H, J = 8.2 Hz, C H 2 CH 2 NH 3 ) 36.0 ( C H 2 NH 3 ) 1.71 (s, 6H, C H 3 ) 21.6 ( C H 2 CH 2 NH 3 ) 1.63 (s, 6H, C H 3 ) 8.8, 8.5 (each C H 3 )

SYNTHESIS OF MONONUCLEAR TETHERED Rh COMPLEX ClH 3 N Cl KO t C 4 H 9 Cl Rh Rh Rh N Cl CH 2 Cl 2 Cl Cl H rt, 9 h H NH 3 Cl Cl 25% yield Spectra data of new complex 1 H NMR (CDCl 3 ) 13 C NMR (CDCl 3 ) δ 3.90 (m, 2H, C H 2 NH 2 ) δ 109.1 (d, C 5 Me 4 ) 97.5 (d, C 5 Me 4 ) 3.59 (br, 2H, N H 2 ) 85.8 (d, C 5 Me 4 ) 2.41 (t, 2H, 3 J = 6.7 Hz, C H 2 CH 2 NH 2 ) 58.0 (s, C H 2 NH 2 ) 1.90 (s, 6H, CH 3 ) 25.4 (s, C H 2 CH 2 NH 2 ) 1.69 (s, 6H, CH 3 ) 9.1 (s, C H 3 ) 8.9 (s, C H 3 )

SYNTHESIS OF CATIONIC TETHERED COMPLEX AND ITS SPECTRAL DATA NH 3 Cl SbF 6 ClH 3 N 1) KO t C 4 H 9 Cl 2) AgSbF 6 PPh 3 Rh Rh Rh N CH 3 CH 2 OH THF Ph 3 P Ph 3 P Cl Cl 2 H H reflux, 7 h rt, 1) 0.5 h 2) 2 h Cl Cl 78% yield 33% yield (after recrystallization) 1 H NMR (DMSO-d 6 ) 1 H NMR (CD 2 Cl 2 ) δ 7.85 (br, 3H, N H 3 ) δ 7.43-7.58 (m, 15H, C 6 H 5 ) 7.71 (m, 6H, C 6 H 5 ) 3.94 (m, 1H) 7.45 (m, 9H, C 6 H 5 ) 3.77 (m, 2H) 2.86 (br, 2H, C H 2 NH 3 ) 2.67 (m, 2H) 2.29 (m, 2H, C H 2 CH 2 NH 3 ) 2.20-2.28 (m, 1H) 1.38 (d, 6H, 4 J HP = 3.2 Hz, C H 3 ) 2.13 (d, 3H, 4 J HP = 7.6 Hz, C H 3 ) 1.07 (d, 6H, 4 J HP = 3.4 Hz, C H 3 ) 1.69 (s, 3H, C H 3 ) 1.21 (s, 3H, C H 3 ) 31 P NMR (DMSO-d 6 ) 0.97 (dd, 3H, J = 0.7, 5.4 Hz, C H 3 ) δ 30.0 (d, J PRh = 144.6 Hz) 31 P NMR (CD 2 Cl 2 ) δ 33.1 (d, J PRh = 141.0 Hz)

STRUCTURE OF TETHERED Rh COMPLEX ClH 3 N KO t C 4 H 9 (3 equiv/Rh) Cl NHTf Cl Rh Rh Rh N + TfN THF Cl Cl H NHTf H NTf reflux, 4 h NH 3 Cl 1 : 2 Tf = SO 2 CF 3 84% yield 1 H NMR (CDCl 3 ) δ 7.59 (m, 2H, C 6 H 4 ) 6.78 (m, 2H, C 6 H 4 ) 4.14 (br, 4H, C H 2 N H 2 ) 2.42 (t, 2H, J = 6.3 Hz, C H 2 CH 2 NH 2 ) 1.86 (s, 6H, C H 3 ) 1.37 (s, 6H, C H 3 ) 19 F NMR (CDCl 3 ) δ & 75.8 (SO 2 C F 3 ) P2 1 /a (#14) R 1 = 0.033 wR 2 = 0.120

CATAYLTIC ACTIVITY OF TETHERED Rh COMPLEX Reduction of acetophenone OH O Rh cat HCO 2 H ・ N(C 2 H 5 ) 3 + Rh CH 3 OH N Cl 5 equiv 70 °C, 6 h H < 1% conv H Cl ketone : Rh = 100 : 1 Rh cat Reductive amination of acetophenone NH 2 OH O Rh cat + + HCOONH 4 Rh CH 3 OH N Cl 5 equiv 70 °C H > 99 : < 1 H Cl ketone : Rh = 100 : 1 38 TOF (h -1 ) Rh cat

CATALYTIC LEUCKART － WALLACH TYPE REDUCTIVE AMINATION OF KETONES NH 2 OH O Rh cat + Cl + HCOONH 4 CH 3 OH Rh 5 equiv 70 °C, 2 h Cl 2 ketone : Rh = 100 : 1 98 : 2 (98% conv) Rh cat Possible mechanism Rh NH 2 O NH Cl NH 3 HCOONH 4 H H Kitamura, M.; Lee, D.; Hayashi, S.; Tanaka, S.; Yoshimura, M. J. Org. Chem. 2002, 67 , 8685

SUMMARY Synthesis of tethered Rh complex with primary amine ClH 3 N KO t C 4 H 9 (1 equiv/Rh) Cl Cl Rh Rh Rh N CH 2 Cl 2 Cl Cl Cl H rt, 9 h H Cl NH 3 Cl Synthesis of analogous tethered Rh complexes SbF 6 Rh Rh Rh N N Cl N TfN Ph 3 P H H H H H NTf H Cl Cl ・ Active catalyst for reductive amination