= 9.3 kcal/mol (TF) = 30.9 kcal/mol (py) G= T S = 9.3 (298 ( 41)) = 2.9 kcal/mol (TF) = 30.9 (298 ( 41)) = 18.7 kcal/mol (py) TF py Mn-Mn
Toleman cone angle θ
Electronic effect of PR 3 groups in LNi(CO) 3 Stronger donor phosphines increase the electrondensity on Ni, which passes some of this increase along to the COs by back bonding. Increase the CO-M back bonding Cone angle
oxidative addition and reductive elimination) +2 +2 +2 +1 + +1
agostic hydride (Brookhart and Green, 1983) γ Η
First direct observation of oxidative addition of a saturated hydrocarbon C- bond Janowicz and Bergman (1982) Molecule D/ kcal (mol) -1-104 C 3-104 C 3 -C 3 88 C 3 -I 56 (C 4 12 K ) 2 Pt, Ir
R. G. Bergman 1982),()(C 6 11 ) C 4 1 C 6 12 Eq. 37) Eq. 38, 39 2 C 6 6 PMe 3 Cp*Ir(PMe 3 ) Cp*Ir(PMe 3 ) bent 1 linear 3 Cp*Ir(PMe 3 ) C 2 isolobal( ) 1 C 2 C C-C 2 - k /k D 1.38 Cp*Ir(PMe 3 ) ) 1.23 C 2 fast
cis Trans
R L M CO L M C R O Two-step mechanism (Fig. 6.1) 1) 2) k-1 >> k2 k-1 << k2 1/kobs 1/[L]
Fe-C Calderazzo 1977 Chiral center 5 Fe 1)R 7 inversion 2)CO 9 retention 16 ) 6 8 In nitroethane 7 (highly stereospecific) In MPA 9 (stereoselective) 13 CO Calderazzo 1977 cis a:b:c:d Me 1:2:0:1 (L=CO in acetone/tf or L= P(OC 2 ) 3 CC 3 in TF (or MPA)) CO 1:2:1:0
R R-M D PhC 2 -Mn) < D C 3 -Mn) PhC 2 -Mn insertion D CF 3 -Mn) D C 3 -Mn) CF 3- Mn insertion R-CO-Mn insertion C 2 F 5 COMn
"agostic" ( terminal R trans R + cis R ML n + C 2 R L n M L n M M C 2 R C 2 R L n C 2 R 3 C L n M L n M L n M + R R R cis or trans
1. 1) oxidative addition) 2) (hydrogenolysis) 3) heterolytic hydrogen cleavage) 2. (hydrogenolysis) 3. heterolytic hydrogen cleavage)
4. Monohydride hydrogenation catalysis 5. Dihydride hydrogenation catalysis 8 Keq 13)= 10 6 M -1
-L -L S= solvent Keq 13)= 10 6 M -1
Wilkinson (III) (I) dimer monomer Wilkinson
1931 Bull Chem Soc Jpn 1956 Nature Raney 1966 (II) Tetrahed,
1968 - Tetrahed, W. S. Knowles 1971 -DIOP Tetrahed,. B. Kagan
Methyl (Z)-α-acetamidocinnamate (MAC) Methyl N-acetamidophenylalanate k 2 ---RDS at 25 C ( E 6 kcal mol -1 ) K 4 ---RDS at -40 C ( E 17 kcal mol -1 )
si Ph O re O 2 C N Ph prochiral
Face-edge conformation of of chelate phosphine ligand in in chiral phosphine-rh(i) complexes NCOC 3 COO α-acylaminocinnamic acid 2 NCOC 3 * COO N-acylphenylalanine Quadrant diagram of complex W. S. Knowles, in Fundamental Research in omogeneous Catalysis, vol 3, M. Tsutsui ed., Plenum, NY, p. 537 (1978). Quadrant diagram of Λ complex
Perspective views of chiral phosphine-rh(i) complexes Perspective views of chiral phosphine-rh(i) complexes W. S. Knowles, in Fundamental Research in omogeneous Catalysis, vol 3, M. Tsutsui ed., Plenum, NY, p. 537 (1978).
Monsanto process for the synthesis of L-DOPA (effective medicine for Parkinson s disease) developed by W.. Knowles.
3. C5-C6 C7-C8 C21-C22 Ergosterol acetate Tritium labeling β ketoalcohol Prostaglandins Birch reduction (arenes) β ketoalcohol
CO 2 + CO + RC C 2 RC 2 C 2 CO + RCC 3 CO 2 1990 700 / Co Co-Th 150 200 atm L:B=3:1 Ruhrchemie 1938 C 7 C 9 300 Rh(CO)(PPh 3 ) 3 25 1 PPh 3 L linear branched RC 2 C 2 C 2 O RCC 3 C 2 O propionaldehyde
C 3 O CoI 2 250 68 MPa, BASF 1960 Monsanto [RhI 2 (CO) 2 ] - 180 40 1960 C 3 I C 3 O 2 O C 3 COO 2 O I [RhI 2 (CO) 2 ] 1 C 3 I C 3 CO I 5 [RhI 3 (C 3 CO)(CO) 2 ] 4 [RhI 3 (C 3 CO)(CO) 2 ] 3 [RhI 3 (C 3 )(CO) 2 ] 2 CO
(Wacker oechst [(C 2 4 )PdCl 2 ] 2 C 3 CO (1894 F. C. Phillips USA) oechst Wacker Chemie 1/2O 2 +2Cl J. Smidt CuCl 2 2CuCl (1956) 2 O [Cl - ] 0.2M 2CuCl 2 [PdCl 4 ] - 2 3 2 O C 2 C 2 O Pd(0) + 2Cl 7 3 4 3 O + 4 5 Pd- [PdCl 5 6 2 ( 2 O)] 6 7 6 C 3 CO ( 2 O)Cl 2 Pd 5 C 3 C O C 2 4 +PdCl 2 + 2 O C 3 CO + Pd +2Cl Pd + 2CuCl 2 PdCl 2 + 2CuCl 2CuCl + 2Cl + 1/2 O 2 2CuCl 2 + 2 O C 2 4 + 1/2 O 2 C 3 CO [PdCl 4 ] 2 8 C 2 4 1 3 Cl [PdCl 3 (C 2 4 )] = -243 kj mol -1 2 2 O Cl [PdCl 2 ( 2 O)(C 2 4 )] 2 O + [PdCl 2 (C 2 C 2 O)( 2 O)] Cl ( 2 O)ClPd 4 CO C 2 Cl
Migratory insertion (P. Cosee, 1964) Co-catalyst MAO(methylalumoxane) ([Al(C 3 )-O] n Carbon-to-metallacycle mechanism (M. L.. Green, 1978) isotactic syndiotactic atactic