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Synthesis of Optically Active Amino Alcohols
Changyou Yuan
Department of Chemistry
Michigan State University
-A survey of major developments after the year 2000
Ph
O
HOOC
NH2
NH OH
O
O
Ph
O
NMe
O
O
OH
Bestain Hapalosin
HN
NH
O
O OH
O
N
S
Ph
Ph
Saquinavir 1
HN O
O
NB O
Ph
Ph
Me
23
Important Free or Functionalized Amino Alcohols
Strategies Available for the Synthesis of Optically Active Amino Alcohols
R1
R2
OH
NH2
R1OH
NH2
O
Reduction of amino acids
R1R2
OH
OH
Substitution of 1,2 diols
R1
R2
O
NX2
Reduction reactions
O
R1 NX
R2+
Cross Coupling reactions
R1R2
Aminohydroxylations
N
R1
+R2
R3R-
or
R
Addition reactionR1
R2
Open epoxides, aziridines
X
R1R2
OH
NH2
Resolutions
OutlinePart 1: Addition reactions
Addition of Carbanions to IminesRadical Addition to Oximes, Hydrazones
Part 2: Reduction reactionsAsymmetric Hydrogenations of α-N-substituted β- Keto Esters
Part 3: Coupling ReactionsCross-Coupling of Ferrocenylideneamine and FerrocenecarboxaldehydesCross-Coupling of Benzylideneamines with AldehydesProline-Catalyzed Assemble of Aldehydes, Ketones, and Amine or Azodicarboxylic Acid Esters
Part 4: Kinetic Resolution of Racemic Epoxides
Conclusion
OutlinePart 1: Addition reactions
Addition of Carbanions to IminesRadical Addition to Oximes, Hydrazones
Part 2: Reduction reactionsAsymmetric Hydrogenations of α-N-substituted β- Keto Esters
Part 3: Coupling ReactionsCross-Coupling of Ferrocenylideneamine and FerrocenecarboxaldehydesCross-Coupling of Benzylideneamines with AldehydesProline-Catalyzed Assemble of Aldehydes, Ketones, and Amine or Azodicarboxylic Acid Esters
Part 4: Kinetic Resolution of Racemic Epoxides
Conclusion
Lithiation of O-benzyl Carbamates–imine Addition
S.Arrasate, E.Lete, N.Sotomayor. Tetrahedron: Asymmetry, 2002, 13, 311–316.
O O
NiPr
MeO
MeO
O
NiPr
MeO
MeO
LiO
NN
N
Ph H
OMePh
OCONiPr2
NHPMP
MeO
MeO
PhOCONiPr2
NHPMP
MeO
MeO
4 (1RS, 2RS)
5 (1RS, 2SR)
s-BuLi, -78oC
TMEDA
72hr
64 % yield syn : anti > 95 : 5OMe
Li N
O
O
NiPr2
Li N
O
O
NiPr2
OMe
syn anti
A B
Asymmetric Lithiation of O-benzylCarbamates–imine Addition
Ph
MeO2C H
O NiPr2
O CO2Me
NiPr2
OH
Ph O
+
91% yield 57 : 43 ( 14% ee)
S R
S.Arrasate, E.Lete, N.Sotomayor. Tetrahedron: Asymmetry, 2002, 13, 311–316.
1. CO2
2. CH2N2
Asymmetric Lithiation of O-benzylCarbamates–imine Addition
R1 R2 Temp Yield(%) D.R e.e. (%)
OCH3
OCH3
OCH3
H
-78oC 6h
-78oC 6h
84
67
>95:5
>95:5
56 (96)
76 (91)
MeO
Ph
OCONiPr2
NHPMP
MeO PhOCH2ONiPr2
NHPMP
MeO
MeO
4 (1R, 2R) major 4 (1S, 2S) minor
S.Arrasate, E.Lete, N.Sotomayor. Tetrahedron: Asymmetry, 2002, 13, 311–316.
Addition of -Sulfinyl Carbanions to N-p-Tolylsulfinylketimines
Sulfoxide T (oC) Yield (%) De (%)
(S) – 1
(R) – 1
(S) – 1
(R) - 1
-78
-78
0
0
82
85
67
65
60
80
>98
>98
J.L.G.Ruano, J.Aleman, M.Prado, I. Fernandez. J. Org. Chem. 2004, 69, 4454-4463. J.L.G.Ruano, J.Aleman. Org. Lett. 2003, 5, 4513-4516.
Me Ph
N
SO
Tol
Me
S
Tol
O
(S)-1
Me
S
Tol
O
(R)-1
LDA
LDA
Ph
S
Tol
OMeTolSOHN
5A 5B
6A 6B
Ph
S
Tol
OMeTolSOHN
Ph
S
Tol
OMeTolSOHN
Ph
S
Tol
OMeTolSOHN
Major
Major
Addition of -Sulfinyl Carbanions to N-p-Tolylsulfinylketimines
Sulfoxide T (oC) Yield (%) de at C(2) (%)
(S) – 2
(R) – 2
(S) – 2
(R) - 2
-78
-78
0
0
77
75
73
70
70
20
80
54
J.L.G.Ruano, J.Aleman, M.Prado, I. Fernandez. J. Org. Chem. 2004, 69, 4454-4463. J.L.G.Ruano, J.Aleman. Org. Lett. 2003, 5, 4513-4516.
C-1 C-2
(S)-sulfinyl ketimine (S)-(2)
(R)-(2)
R
S
S
S
Me Ph
N
SO
Ar
EtS
Tol
O
EtS
Tol
O
PhS
Tol
OMeTolSOHN
Me7A
8A
PhS
Tol
O
Me
TolSOHN Me
PhS
Tol
OMeTolSOHN
MePh
STol
OMeTolSOHN
Me
1 S
S S
S2 S R
R S
S
(S)-2
(R)-2
LDA
LDA
7B
8B
Major
Major
J.L.G.Ruano, J.Aleman, M.Prado, I. Fernandez. J. Org. Chem. 2004, 69, 4454-4463. J.L.G.Ruano, J.Aleman. Org. Lett. 2003, 5, 4513-4516.
Addition of -Sulfinyl Carbanions to N-p-Tolylsulfinylketimines-Stereocontrol
Ph
STol
OMeTolSOHN
5A
6A
Ph
STol
OMeTolSOHN
Major
Major
S
S
Me Ph
N
SO
Tol
MeS
Tol
O
(S)-1
MeS
Tol
O
(R)-1
LDA
LDAor
S
J.L.G.Ruano, J.Aleman, M.Prado, I. Fernandez. J. Org. Chem. 2004, 69, 4454-4463. J.L.G.Ruano, J.Aleman. Org. Lett. 2003, 5, 4513-4516.
Addition of -Sulfinyl Carbanions to N-p-Tolylsulfinylketimines - stereocontrol
Me Ph
N
SO
Ar EtS
Tol
O
A isomers
PhS
Tol
OMeArSOHN
Me
PhS
Tol
OMeArSOHN
Me
RS(R)-2
LDA
B isomers
Major minor
- 78oC 20 % de
0oC 54 % de
J.L.G.Ruano, J.Aleman, M.Prado, I. Fernandez. J. Org. Chem. 2004, 69, 4454-4463. J.L.G.Ruano, J.Aleman. Org. Lett. 2003, 5, 4513-4516. M.Crucianelli, P.Bravo, A.Arnone, E.Corradi, S.V.Meille, M.Zanda. J. Org. Chem. 2000, 65, 2965-2971.
Addition of -Sulfinyl Carbanions to N-p-Tolylsulfinylketimines – Demasking Steps
PhS
Tol
OMeTolSOHN TFA, 0oC
MeOH PhS
Tol
OMeH2N Boc2O, NEt3
CH3CN PhS
Tol
OMeBocHN
TFA, sym-collidine 1) NaBH4, KCO32) HCl, THF
Ph
MeClH3N
Ph
MeN
OOCCF3
BocS Tol
OH
1 2 3
4 5
Radical Addition of Hydroxymethyl and Vinyl Groups to C=N Bonds
G.K.Friestad, S.E.Massari. J. Org. Chem. 2004, 69, 863-875. G.K.Friestad, S.E.Massari. Org. Lett. 2000, 2, 4237-4240.
R1R2
NH2 NX
R1R2
Stereocontrol
NX
SPhSiO
R
O Si
R
NHX
PhS
R
OSi Br
NX
Bu3Sn
OSi
NX
R
NX
R
OSi
O
NX
R
Si SPh
NHX
R
OH OH
NHX
R
OH
Atom Abstraction/Cyclization
Addition/Cyclization
Hydroxymethyl Addition to Oxime Ethers
G.K.Friestad, S.E.Massari. J. Org. Chem. 2004, 69, 863-875. G.K.Friestad, S.E.Massari. Org. Lett. 2000, 2, 4237-4240.
NOBn
R1
OSi Br
Bu3SnH
O Si
R1
NHOBn
AIBN
ONOBnR1
OH
O
N
OO
OBnR1
OH O
R1
OH
O
NOBn
R1=Me: anti/syn=9:1 52%
1. ClCO2Me
2. KF, KHCO3, H2O2 THF, MeOH
1 2
cis-3 4 trans-3
anti=cis-3 + 4syn=trans-6
R1=Ph: no synthetically useful yields
Hydroxymethyl Addition to Hydrazones
R Me tBu iPr Ph
Anti-7:syn-7
Yield (%)
79:21
76
85:15
68
96:4
80
>98:2
57
G.K.Friestad, S.E.Massari. J. Org. Chem. 2004, 69, 863-875. G.K.Friestad, S.E.Massari. Org. Lett. 2000, 2, 4237-4240.
NNPh2
R
OSi Br
Bu3SnH
O Si
R
NHNPh2
AIBN, PhH
KF, KHCO3, H2O2 THF, MeOH
5 6
R
OHOH
NHNPh2
anti-7
R
OHOH
NHNPh2
syn-7
Tandem Thiyl Addition-Cyclization: Vinyl Additionto Hydrazones
R Yield(%) Ratio (anti/syn)
Me 77 90:10
tBu 67 94:6
iPr 61 98:2
Ph 49 >98:2
G.K.Friestad, S.E.Massari. J. Org. Chem. 2004, 69, 863-875. G.K.Friestad, T.Jiang, G.M.Fioroni. Tetrahedron: Asymmetry, 2003, 14 , 2853–2856.
NNPh2
R
OSi
1. PhSH, AIBN, cyclohexane, refulx 2. KF, MeOH R
OH
NHNPh2
8 10
O Si
R
NHNPh2
9
SPh
Diastereocontrol in Radical Addition – CyclizationBeckwith-Houk Model
R
OHOH
NHNPh2
R
OH
NHNPh2
7 8
RA Value
(kcal/mol)
dr of 7 dr of 8
Me 1.6 79:21 90:10tBu 1.8 85:15 94:6iPr 2.2 96:4 98:2
Ph 2.9 >98:2 >98:2
G.K.Friestad, S.E.Massari. Org. Lett. 2000, 2, 4237-4240. G.K.Friestad, S.E.Massari. J. Org. Chem. 2004, 69, 863-875. G.K.Friestad, T.Jiang, G.M.Fioroni. Tetrahedron: Asymmetry, 2003, 14 , 2853–2856.
R
OHOH
NHNPh2
R
OH
NHNPh2
7 8
Comparison of the Addition Reactions
Me Ph
NS
O
Ar
S EtS
Tol
O
PhS
Tol
OMeTolSOHN
Me
SS
(R)-2
LDA
NNPh2
R
OSi
R
RR'
OH
NHNPh2
1 2
1: R = CH2Br; CH=CH22: R = CH2OH, CH=CH2
StereocontrolDe/ee (%)
Yield(%)
Anti
or syn
Chiral amine (additive)>95:5/
56-7667-84 syn
Sulfinylketimine and sulfinyl carbanions
60:40~
90:10 /-70-77 both
Substrate control and
Beckwith-Houk model
80:20~
>98:2/-50-80 anti
O O
NiPr
MeO
MeO
s-BuLi, -78oC
(-)-sparteinPh
OCONiPr2
NHPMP
MeO
MeO4 (1R, 2R)
NPh
H
OMe
OutlinePart 1: Addition reactions
Addition of Carbanions to IminesRadical Addition to Oximes, Hydrazones
Part 2: Reduction reactionsAsymmetric Hydrogenations of α-N-substituted β- Keto Esters
Part 3: Coupling ReactionsCross-Coupling of Ferrocenylideneamine and FerrocenecarboxaldehydesCross-Coupling of Benzylideneamines with AldehydesProline-Catalyzed Assemble of Aldehydes, Ketones, and Amine or Azodicarboxylic Acid Esters
Part 4: Kinetic Resolution of Racemic Epoxides
Conclusion
C.Mordant, P.Dünkelmann, V.R,Vidal, J.P.Genet. Eur. J. Org. Chem. 2004, 3017-3026.
Asymmetric Hydrogenations of α-N-substituted β-keto esters - Preparation the Syn – Amino Alcohols
R OEt
O O
NHCOPh
R OEt
OH O
2 mol% [Ru(S)-SYNPHOSBr2]
H2 (120 bar), 80oC, 4days
CH2Cl2
3 (2R, 3S)-5
NHCOPh
O
O
O
O
PPh2
PPh2
(S)-SYNPHOS®
R Yield (%) de (%) ee (%)
C3H7 81 71 75
BnO-C4H8 53 93 >99
C5H11 77 98 99
C15H31
iPr
82
92
98
98
97
97
Asymmetric Hydrogenations of α-N-substituted β-keto esters - Preparation the Anti – Amino Alcohols
Substrate SYNPHOS configuration Yield (%) de anti (%) ee (%)
R = C3H7
R = BnO-C4H8
R = C5H11
R = C15H31
R = iPr
S
R
S
R
S
R
SR
S
R
90
90
94
93
85
90
83
85
90
96
86
86
92
93
93
93
96
98
99
97
92 (2S, 3S)
93 (2R, 3R)
92 (2S, 3S)
93 (2R, 3R)
91 (2S, 3S)
91 (2R, 3R)
96 (2S, 3S)
96 (2R, 3R)
97 (2S, 3S)
96 (2R, 3R)C.Mordant, P.Dünkelmann, V.R,Vidal, J.P.Genet. Eur. J. Org. Chem. 2004, 30173026.
R OEt
O O
NH2HCl
R OEt
OH O
NHCOPh
1. 2 mol% [Ru(S)-SYNPHOSBr2]
H2 (12 bar), 50oC, 24hr
CH2Cl2 + R'OH
2. (PhCO)2O, NEt3, CH2Cl24 (2S, 3S)-5
OutlinePart 1: Addition reactions
Addition of Carbanions to IminesRadical Addition to Oximes, Hydrazones
Part 2: Reduction reactionsAsymmetric Hydrogenations of α-N-substituted β- Keto Esters
Part 3: Coupling ReactionsCross-Coupling of Ferrocenylideneamine and FerrocenecarboxaldehydesCross-Coupling of Benzylideneamines with AldehydesProline-Catalyzed Assemble of Aldehydes, Ketones, and Amine or Azodicarboxylic Acid Esters
Part 4: Kinetic Resolution of Racemic Epoxides
Conclusion
Y.Tanaka, N.Taniguchi, T.Kimura, M.Uemura. J. Org. Chem. 2002, 67, 9227-9237. Y.Tanaka, N.Taniguchi,M.Uemura. Org. Lett. 2002, 4, 835-838..
Cross-Coupling of N-TosylFerrocenylideneamine and Ferrocenecarboxaldehydes
Imine 2 ( X ) 3 yield(%) 4 yield(%) 5 yield(%)
Me
Bn
Ph
NMe2
NHSO2Ph
SO2Ph
Ts
Ms
0
0
0
0
0
92
88
94
95
96
96
98
92
Trace
Trace
trace
0
0
95
0
0
0
0
0
Cross-Coupling of Planar Chiral N-TosylFerrocenylideneamine and Ferrocenecarboxaldehydes
aldehyde 7 (% ee) imine 8 9 yield (%) %ee 9
R1=Me (95)
R1=Me
R1=I (95)
R1=Br (97)
R1= H
R1= HR1= H
R2=MeR2=I R2=IR2=Br R2=MeR2=IR2=Br
92
93
90
93
91
96
95
95
95
95
97
92
94
97
Y.Tanaka, N.Taniguchi, T.Kimura, M.Uemura. J. Org. Chem. 2002, 67, 9227-9237. Y.Tanaka, N.Taniguchi,M.Uemura. Org. Lett. 2002, 4, 835-838..
Reaction Mechanism of Cross-Coupling withN-Tosyl Ferrocenylideneamines
Y.Tanaka, N.Taniguchi, T.Kimura, M.Uemura. J. Org. Chem. 2002, 67, 9227-9237. Y.Tanaka, N.Taniguchi,M.Uemura. Org. Lett. 2002, 4, 835-838.
Reaction Mechanism of Cross-Coupling withN-Tosyl Ferrocenylideneamines
CpFe
CHO
R
7
R
R
Y.Tanaka, N.Taniguchi, T.Kimura, M.Uemura. J. Org. Chem. 2002, 67, 9227-9237. Y.Tanaka, N.Taniguchi,M.Uemura. Org. Lett. 2002, 4, 835-838.
CpFe
CHO
ent-7
R
92 % enantiopure
97 % enantiopure
Cross-Coupling of Benzylideneamines with Aldehydes
NX
R
CHO
R
CHOCr(CO3)
+ or
1. SmI2, THF, 0oC to rt
2. Ac2O, pyr3. hv-air ( for chromium complex)
R
NHX
OAc
29 11 14 30
imine aldehyde yield (%) Syn/anti
X=Ms
X=Ts
11 R=H, Me, OMe
14 R=H, Me, OMe
11 R=H, Me, OMe, Cl
14 R=H, Me, OMe, Cl
70-93
63-89
52-81
33-73
50/50 – 54/56
60/40 – 67/33
70/30 – 87/13
95/5 – 97/3
Y.Tanaka, N.Taniguchi, T.Kimura, M.Uemura. J. Org. Chem. 2002, 67, 9227-9237. Y.Tanaka, N.Taniguchi,M.Uemura. Org. Lett. 2002, 4, 835-838.
Cross-Coupling of Benzylideneamines with Aldehydes
Y.Tanaka, N.Taniguchi, T.Kimura, M.Uemura. J. Org. Chem. 2002, 67, 9227-9237. Y.Tanaka, N.Taniguchi,M.Uemura. Org. Lett. 2002, 4, 835-838.
NTs
Me
CHO
+
1. SmI2, THF, 0oC to rt
2. Ac2O, pyr
3. hv-air ( for chromium complex)
Me
NHTs
OAc
29b 17b 34Cr(CO3)
60%
>99% ee
NTs
Me
CHO
+
1. SmI2, THF, 0oC to rt
2. Ac2O, pyr
3. hv-air ( for chromium complex)
Me
NHTs
OAc
29b ent-17b ent-34Cr(CO3)
60%
>99% ee
Proline-Catalyzed Direct Asymmetric Mannich Reaction
B.List, P.Pojarliev, W.T.Biller, H.J. Martin. J. Am. Chem. Soc. 2002, 124,827-833.
Proline-Catalyzed Assemble of Aldehydes, Ketones, and Azodicarboxylic Acid Asters
N.S. Chowdari, D. B. Ramachary, C.F.Barbas. Org. Lett., 2003, 5 ,1685-1688.
R
O
R
O N
NCbz
Cbz
S-Proline (20 mol%)
CH3CN (0.33M)r.t. 96 h
++ N
O OH
R
N
O OHHNCbz
Cbz
HNCbz
Cbz
R
+
StereocontrolDe/ee (%)
Yield(%)
Anti
or syn
Ferrocenylideneamines
Ferrocenecarboxaldehydes
>95/
92-9790-95 anti
planar chiral benzaldehyde chromium
complexes
90/
>9933-81 syn
Proline20-95/
60->9960-90 syn
Comparison of the Cross-Coupling Reactions
NXR
CHO
R
CHO
Cr(CO3)
R
NHX
OAc+
or
1. SmI2, THF, 0oC to rt2. Ac2O, pyr3. hv-air
RH R' R'
O O O
OH
NHR''ArNH2
or
N
N
Cbz
Cbz
R = H, OH
+ +Proline
OutlinePart 1: Addition reactions
Addition of Carbanions to IminesRadical Addition to Oximes, Hydrazones
Part 2: Reduction reactionsAsymmetric Hydrogenations of α-N-substituted β- Keto Esters
Part 3: Coupling ReactionsCross-Coupling of Ferrocenylideneamine and FerrocenecarboxaldehydesCross-Coupling of Benzylideneamines with AldehydesProline-Catalyzed Assemble of Aldehydes, Ketones, and Amine or Azodicarboxylic Acid Esters
Part 4: Kinetic Resolution of Racemic Epoxides
Conclusion
Aminolytic Kinetic Resolution with Amines
G.Bartoli, M.Bosco, A.Carlone, M.Locatelli, M.Massaccesi, P.Melchiorre, L.Sambri. Org. Lett. 2004, 6, 2173-2176.
R1 R2 T (oC) t (h) Yield (%) Ee of 4 (%) Ee of 2 (%)
H
H
H
H
OMe
OMeOMe
H
H
OMe
OMe
H
HH
rt
-10
rt
0
rt
-10-10
18
36
18
24
12
2424
91
47
89
60
98
9393
86
>99
88
93
83
9494
30
80
81
PhPh
O
NH2
R1R2+
(+/-) 2
(R,R)-1 (5 mol%)
CH2Cl2
3
2 equiv 1 equiv
PhPh
NH
OH4
anti/syn > 99/1
R1R2
Aminolytic Kinetic Resolution with Amines
G.Bartoli, M.Bosco, A.Carlone, M.Locatelli, M.Massaccesi, P.Melchiorre, L.Sambri. Org. Lett. 2004, 6, 2173-2176.
G.Bartoli, M.Bosco, A.Carlone, M.Locatelli, M.Massaccesi, P.Melchiorre, L.Sambri. Org. Lett. 2004, 6, 3973-3975..
Aminolytic Kinetic Resolution with carbamates
(S,S)-catalyst (1.5 mol%)
Additive(3 mol%)
20h, rt / in air
R Cat. (M) Additive Solvent Conv (%) ee(%)
Boc
Boc
Boc
Boc
BocBoc
Cbz
COOEt
Fmoc
Cr(Cl)
Co(OAc)
Co
Co
CoCo
Co
Co
Co
None
None
AcOH
p-nitrobenzoic acid
p-nitrobenzoic acidp-nitrobenzoic acid
p-nitrobenzoic acid
p-nitrobenzoic acid
p-nitrobenzoic acid
CH2Cl2
CH2Cl2
CH2Cl2
CH2Cl2
TBMETBME
TBME
TBME
TBME
0
45
65
80
>95>95
95
>95
75
96
96
>99
9999
99.5
99
99.5
Aminolytic Kinetic Resolution with carbamates
G.Bartoli, M.Bosco, A.Carlone, M.Locatelli, M.Massaccesi, P.Melchiorre, L.Sambri. Org. Lett. 2004, 6, 3973-3975..
R Time (h) Yield (%) ee(%)
CH3,, 6a
(CH2)3CH3, 6b
(CH2)4CH=CH2, 6c
c-C6H11, 6d
CH2O(1-naphthyl), 6e
CH2Cl, 6f
C6H5, 6g
p-BrC6H4, 6h
o-NO2C6H4, 6i
24
24
24
24
24
24
36
48
48
99
99
99
84
95
87
90
76
62
99.3
99.2
99.7
99.9
99.5
99.9
99.9
99.8
99.8
StereocontrolDe/ee (%)
Yield(%)
Anti
or syn
Chiral Cr(Salen)>99/
74-99.544-98 anti
Chiral Co(Salen)-/
>9962-99 -
Comparison of the Resulution Methods
NH2Boc RO
RNHBoc
OH
+
(+/-)2 equiv
chiral catalyst
1 equiv
R1 R2O+
(+/-)
2 equiv
PhPh
NH
OH
chiral catalyst
1 equiv
ArNH2
Conclusion
• Optically active amino alcohols have been prepared through: Addition of carbanions, free radicals to C=N.
Asymmetric hydrogenations of α-N-substituted β- keto esters
Coupling of imines and aldehyes
Kinetic resolution of racemic epoxides
• Much remains to be done:Scope of substrates
Relative and absolute stereochemisry
Acknowledgement • Dr. Hollingsworth
• Dr. Wulff
• Dr. Borhan
• Hollingsworth GroupXuezheng Carol
Chang Xiaoyu
Li Kun
Zhen Trevor
Joel Felica
Proline-Catalyzed Direct Asymmetric Three Component Mannich Reaction
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Proline-Catalyzed assemble of aldehydes, ketones, and azodicarboxylic acid esters
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Asymmetric hydrogenations of α-N-substitutedβ-keto esters
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Addition of -Sulfinyl Carbanions to N-p-Tolylsulfinylketimines - stereocontrol
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