Unit 2 Stereocontrolled Alkylationweb.mit.edu/5.512/www/lectures07/5.512 Lecture 7.pdf · B. L....
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Massachusetts Institute of Technology Organic Chemistry 5.512 March 16, 2007 Prof. Rick L. Danheiser Unit 2 Stereocontrolled Alkylation and Related Electrophilic Substitution Strategies Special Issue on Asymmetric Organocatalysis Accts. Chem. Res. 2004, 37, 487-631 "Asymmetric Organocatalysis" A. Berkessel and H. Gröger Wiley-VCH, 2005 V. Catalytic Methods α-Oxidation of Aldehydes and Ketones (H. Yamamoto, MacMillan, Zhong, Y. Hayashi) Alkylation of Imine Derivatives of α-Amino Esters (O'Donnell, Corey, Maruoka) Tsuji Allylation of Ketones (Stoltz, Trost) Enantioselective Protonation Strategies (Fu) Catalysis by Enzymes Transition Metal Organometallic Catalysis "Organocatalysts"
Transcript of Unit 2 Stereocontrolled Alkylationweb.mit.edu/5.512/www/lectures07/5.512 Lecture 7.pdf · B. L....
Massachusetts Institute of TechnologyOrganic Chemistry 5.512
March 16, 2007Prof. Rick L. Danheiser
Unit 2Stereocontrolled Alkylation
and Related Electrophilic Substitution Strategies
Special Issue onAsymmetric Organocatalysis
Accts. Chem. Res. 2004, 37, 487-631
"Asymmetric Organocatalysis"A. Berkessel and H. Gröger
Wiley-VCH, 2005
V. Catalytic Methods α-Oxidation of Aldehydes and Ketones (H. Yamamoto, MacMillan, Zhong, Y. Hayashi) Alkylation of Imine Derivatives of α-Amino Esters (O'Donnell, Corey, Maruoka) Tsuji Allylation of Ketones (Stoltz, Trost) Enantioselective Protonation Strategies (Fu)
Catalysis by Enzymes Transition Metal Organometallic Catalysis "Organocatalysts"
Asymmetric Organocatalysis: Early Milestones
H. Pracejus Liebigs Ann. Chem. 1960, 634, 9; J. Prakt. Chem. 1964, 24, 195
CPh
MeO
1 mol% cat*MeOH, tol
PhOMe
O
H Me
93% 74% ee
Z. G. Hajos, D. R. Parrish J. Org.Chem. 1974, 39, 1615; also U. Eder, G. Sauer, and R. Wiechert . . . . see Org. Synth. Coll. Vol. 7, 363 and 368
cat* is O-acetyl quinine
N
NH
HOAc
MeO
+
94 : 670-76%, (99.4 : 0.6 after recrystallization)
+
1) 0.075 eq L-proline DMF, 16° 2-3 d2) H2SO4, DMF 95° 4 h
AcOH, H2O 70° 1-2 h
O
OO
OOO
OO
O O
E. J. J. Grabowski et al. J. Am. Chem. Soc. 1984, 106, 446; J. Org. Chem. 1987, 52, 4745
Cl
Cl
MeO
Ph
O10 mol% cat*50% aq NaOHCH3Cl, toluene
20° 18 h
95%, 92% ee
Cl
Cl
MeOPh
O
CH3
cat*
N
N H
OHH
CF3
Br
cinchoninium bromidederivative
Martin J. O'DonnellIUIPUI
Enantioselective Organocatalytic Oxidation of Aldehydes with Nitrosobenzene
Alkylation of Imine Derivatives of α-Amino Esters
Yamamoto, H.; Momiyama N.Chem. Commun. 2005, 3514
Review
Hisashi YamamotoUniversity of Chicago
David MacMillanPrinceton University
Reviews on Catalytic, Enantioselective "Heterofunctionalization" of Carbonyl Compounds Janey, J. M. Angew. Chem. Int. Ed. 2005, 44, 4292 Guillena, G.; Ramon, D. J. Tetrahedron: Asymmetry 2006, 17, 1465 Marigo, M; Jorgensen, K. A. Chem. Commun. 2006, 2001
Enantioselective Tsuji Allylation
MinireviewYou, S.-L.; Dai, L.-X. . Angew. Chem. Int. Ed. 2006, 45, 5246
OSiMe30.35 equiv TBAT (Bu4NPh3SiF2)
6.25 mol% ligand2.5 mol% Pd2(dba)3
THF, rt
95%, 87% ee
O
OO
O
PPh2 N
O
(S)-t-Bu-PHOX
OO
O
Behenna, D. C.; Stoltz, B. M. J. Am. Chem. Soc. 2004, 126, 15,044Trost, B. M.; Xu, J. J. Am. Chem. Soc. 2005, 127, 2846Trost, B. M.; Xu, J. J. Am. Chem. Soc. 2005, 127, 17180Trost, B. M. Bream, R. N.; Xu, J. Angew. Chem. Int. Ed. 2006, 45, 3109Braun, M.; Meier, T. Angew. Chem. Int. Ed. 2006, 45, 6952
Case Study
O
O
OH
(+)-Dichroanone
McFadden, R. M.; Stoltz, B. M.J. Am. Chem. Soc. 2006, 128, 7738
Enantioselective Protonation StrategiesReview: J.-C. Plaquevent Tetrahedron Asymmetry 2004, 15, 3653
Enantioselective Addition of Amines to Ketenes Catalyzed by a Planar-Chiral DerivativeB. L. Hodous; G. C. Fu J. Am. Chem. Soc. 2002, 124, 10,006
C R
Ar
OR
O
NNH
NC NC
ArFe
MeMe
Me Me
Me
N
N
up to 98% ee(–)-1
2% (–)-1
toluene, r.t.
N
NC
H catalyst*
*
O
R1
R
R
R1CO
N
NC
protonation of an achiral enolateby a chiral Brønsted acid catalyst:
the turnover-limiting and stereochemistry-determining step?
H catalyst*
O
R1
H R
NH
NC
catalyst*
N
NC
7
8
R
O
N
NC
Ar
LiOHNaBH4
LiAlH(Ot-Bu)3
88% 84%Me
O
Ph
HO
i-Pr
O
Ph
98%
BnO
72%
Me
O
NOMe
Et
O
Ph
H
BnHO
MeN
H2O2
BnOH,cat. [Et4N]CN
NH95%
2
3 4 5
6
