Reversal of diastereoselectivity in the benzylation of the lithium enolates of phosphonopropanoamides by changing the base equivalents
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[1] Delong Liu,et al. Reversal in enantioselectivity for the palladium-catalyzed asymmetric allylic substitution with novel metallocene-based planar chiral diphosphine ligands , 2008 .
[2] S. Luis,et al. Efficient chirality switching in the addition of diethylzinc to aldehydes in the presence of simple chiral alpha-amino amides. , 2007, Angewandte Chemie.
[3] O. García-Barradas,et al. A Convenient Method for the Preparation of Chiral Phosphonoacetamides and Their Horner—Wadsworth—Emmons Reaction. , 2007 .
[4] Antonio Ramirez,et al. Lithium diisopropylamide: solution kinetics and implications for organic synthesis. , 2007, Angewandte Chemie.
[5] P. Stephens,et al. Asymmetric Michael reaction: novel efficient access to chiral β-ketophosphonates , 2007 .
[6] W. Zeng,et al. Hydrogen-bonding directed reversal of enantioselectivity. , 2007, Journal of the American Chemical Society.
[7] J. Lex,et al. Reversal of Enantioselectivity by Catalyst Protonation: Asymmetric Hydrocyanation of Imines with Oxazaborolidines , 2006 .
[8] J. D'angelo,et al. The asymmetric Michael-type alkylation of chiral β-enamino esters: critical role of a benzyl ester group in the racemization of adducts , 2005 .
[9] J. Vicario,et al. (S,S)-(+)-pseudoephedrine as chiral auxiliary in asymmetric aza-Michael reactions. Unexpected selectivity change when manipulating the structure of the auxiliary. , 2005, The Journal of organic chemistry.
[10] T. Igarashi,et al. Small amounts of achiral beta-amino alcohols reverse the enantioselectivity of chiral catalysts in cooperative asymmetric autocatalysis. , 2005, Journal of the American Chemical Society.
[11] D. Du,et al. Asymmetric Henry reaction catalyzed by C2-symmetric tridentate bis(oxazoline) and bis(thiazoline) complexes: metal-controlled reversal of enantioselectivity. , 2005, The Journal of organic chemistry.
[12] C. Cativiela,et al. Asymmetric alkylation of dimethoxyphosphoryl-N-[1-(S)-alpha-methylbenzyl]acetamide enolates. Synthesis of both stereoisomers from the same source of chirality by changing the equivalents of LDA. , 2005, Chemical communications.
[13] L. Belvisi,et al. Stereoselective synthesis of Cα-tetrasubstituted azabicyclo[X.3.0]alkane amino acids , 2004 .
[14] A. Wagner,et al. Kinetic resolution of amines: a highly enantioselective and chemoselective acetylating agent with a unique solvent-induced reversal of stereoselectivity. , 2004, Angewandte Chemie.
[15] C. Casey,et al. Reversal of enantioselectivity in the hydroformylation of styrene with [2S,4S-BDPP]Pt(SnCl3)Cl at high temperature arises from a change in the enantioselective-determining step. , 2004, Journal of the American Chemical Society.
[16] M. Huffman,et al. Michael reactions of pseudoephedrine amide enolates: effect of LiCl on syn/anti selectivity. , 2004, The Journal of organic chemistry.
[17] B. Trost,et al. Direct catalytic asymmetric aldol additions of methyl ynones. Spontaneous reversal in the sense of enantioinduction. , 2004, Journal of the American Chemical Society.
[18] S. Tomoda,et al. Origin of stereochemical reversal in Meyers-type enolate alkylations. Importance of intramolecular Li coordination and solvent effects. , 2004, Organic letters.
[19] Jian Zhou,et al. Controllable enantioselective Friedel-Crafts reaction between indoles and alkylidene malonates catalyzed by pseudo-C3-symmetric trisoxazoline copperII complexes. , 2004, The Journal of organic chemistry.
[20] H. Danjo,et al. P-stereogenic P/N hybrid ligands: a remarkable switch in enantioselectivity in palladium-catalyzed asymmetric allylation ☆ , 2004 .
[21] M. Bergdahl,et al. The remarkable ability of lithium ion to reverse the stereoselectivity in the conjugate addition of Li[BuCuI] to a chiral N-crotonyl-2-oxazolidinone. , 2003, Organic letters.
[22] S. Tomoda,et al. Origin of stereochemistry in Meyers enolate alkylations. Importance of major enolate structure and population in tetrahydrofuran , 2003 .
[23] M. Franzini,et al. Toggling enantioselective catalysis--a promising paradigm in the development of more efficient and versatile enantioselective synthetic methodologies. , 2003, Chemical Society reviews.
[24] K. Furusawa,et al. Efficient stereodivergent synthesis of erythro- and threo-sphingosines: unprecedented reversal of the stereochemistry in the addition , 2002 .
[25] M. Sibi,et al. Temperature dependent reversal of stereochemistry in enantioselective conjugate amine additions , 2002 .
[26] B. Feringa,et al. Copper phosphoramidite catalyzed enantioselective ring-opening of oxabicyclic alkenes: remarkable reversal of stereocontrol. , 2002, Organic letters.
[27] R. K. Boeckman,et al. Toward the development of a general chiral auxiliary. 9. Highly diastereoselective alkylations and acylations to form tertiary and quaternary centers. , 2001, Organic letters.
[28] M. Kanai,et al. Switching enantiofacial selectivities using one chiral source: catalytic enantioselective synthesis of the key intermediate for (20S)-camptothecin family by (S)-selective cyanosilylation of ketones. , 2001, Journal of the American Chemical Society.
[29] M. Sibi,et al. Reversal of Stereochemistry in Enantioselective Transformations. Can They Be Planned or Are They Just Accidental , 2001 .
[30] A. Meyers,et al. Chiral Non-Racemic Bicyclic Lactams. Auxiliary-Based Asymmetric Reactions , 2000 .
[31] Yoshihiko Ito,et al. Catalytic asymmetric hydrogenation of α-(acetamido)acrylates using TRAP trans-chelating chiral bisphosphine ligands: Remarkable effects of ligand P-substituent and hydrogen pressure on enantioselectivity , 2000 .
[32] E. Juaristi,et al. Stereoselective alkylation of C2-symmetric chiral N-phthaloylglycinamides in the preparation of enantiopure α-amino acids , 2000 .
[33] N. Nomura,et al. Substituent Effects of Ligands on Asymmetric Induction in a Prototypical Palladium-Catalyzed Allylation Reaction: Making Both Enantiomers of a Product in High Optical Purity Using the Same Source of Chirality , 1999 .
[34] M. Murakami,et al. CATALYTIC ASYMMETRIC 4 + 1 CYCLOADDITION OF VINYLALLENES WITH CARBON MONOXIDE : REVERSAL OF THE INDUCED CHIRALITY BY THE CHOICE OF METAL , 1999 .
[35] S. Kobayashi,et al. A switch of enantiofacial selectivity in chiral ytterbium-catalyzed 1,3-dipolar cycloaddition reactions , 1999 .
[36] J. Blake,et al. Stereoselective Alkylations in Rigid Systems. Effect of Remote Substituents on π-Facial Additions to Lactam Enolates. Stereoelectronic and Steric Effects , 1998 .
[37] K. Gothelf,et al. MOLECULAR SIEVE DEPENDENT ABSOLUTE STEREOSELECTIVITY IN ASYMMETRIC CATALYTIC 1,3-DIPOLAR CYCLOADDITION REACTIONS , 1998 .
[38] N. Nomura,et al. Unprecedented Electronic and Steric Effects in Palladium-Catalyzed Asymmetric Allylation: Switching of Enantioselectivity with a Single Chiral Backbone , 1996 .
[39] A. Myers,et al. Practical Syntheses of Enantiomerically Enriched γ-Lactones and γ-Hydroxy Ketones by the Alkylation of Pseudoephedrine Amides with Epoxides and Their Derivatives , 1996 .
[40] C. Alvarez-Ibarra,et al. Asymmetric Alkylation of 8-Phenylmenthyl N-[Bis(methylthio)methylene]glycinate Enolates. Synthesis of D- and L-.alpha.-Amino Acids from a Single Chiral Precursor , 1995 .
[41] K. Ohe,et al. Chiral Oxazolinylferrocene-Phosphine Hybrid Ligand for the Asymmetric Hydrosilylation of Ketones , 1995 .
[42] J. L. Gleason,et al. Practical method for the synthesis of D- or L-.alpha.-amino acids by the alkylation of (+)- or (-)-pseudoephedrine glycinamide. , 1995 .
[43] J. D'angelo,et al. Methyl methacrylate as acceptor in the asymmetric Michael reaction using chiral β-enaminoesters: Simultaneous, complete stereocontrol of a quaternary carbon center and a tertiary one in the β-position , 1995 .
[44] T. Kawabata,et al. Direct Asymmetric .alpha.-Alkylation of Phenylalanine Derivatives Using No External Chiral Sources , 1994 .
[45] J. L. Gleason,et al. Use of Pseudoephedrine as a Practical Chiral Auxiliary for Asymmetric Synthesis , 1994 .
[46] H. Ishitani,et al. Lanthanide (III)-catalyzed enantioselective Diels-Alder reactions. Stereoselective synthesis of both enantiomers by using a single chiral source and a choice of achiral ligands , 1994 .
[47] R. Bridges,et al. 2,3-Pyrrolidinedicarboxylates as Neurotransmitter Conformer Mimics: Enantioselective Synthesis via Chelation-Controlled Enolate Alkylation , 1994 .
[48] I. Hachiya,et al. Asymmetric Diels-Alder reactions catalyzed by chiral lanthanide(III) trifluoromethanesulfonates. Unique structure of the triflate and stereoselective synthesis of both enantiomers using a single chiral source and a choice of achiral ligands , 1994 .
[49] K. Tomioka,et al. Solvent effect and NMR behaviour in a chiral amidophosphine mediated reaction of organocuprate with chalcone , 1993 .
[50] D. Romo,et al. Chiral non-racemic bicyclic lactams. Vehicles for the construction of natural and unnatural products containing quaternary carbon centers. , 1991 .
[51] Robert M. Williams,et al. Asymmetric synthesis of monosubstituted and .alpha.,.alpha.-disubstituted .alpha.-amino acids via diastereoselective glycine enolate alkylations , 1991 .
[52] D. Seebach,et al. Herstellung chiraler elektrophiler Glycin- und (E)-2,3-Dehydroaminosäure-Derivate aus 2-t-Butyl-3-methyl-4-oxo-1-imidazolidincarbonsäure-t-butylester (Boc-BMI) , 1991 .
[53] P. Wipf,et al. Stereochemical control in the ester enolate Claisen rearrangement. 2. Chairlike vs boatlike transition-state selection , 1991 .
[54] S. Kiyooka,et al. Dramatic changes in diastereoselectivity with the quantity of titanium tetrachloride used in Lewis acid mediated reactions of allylsilane with .alpha.-amino aldehydes , 1989 .
[55] D. Seebach. Structure and Reactivity of Lithium Enolates. From Pinacolone to Selective C‐Alkylations of Peptides. Difficulties and Opportunities Afforded by Complex Structures , 1988 .
[56] J. McCauley,et al. Opposite high diastereoselectivity in the carbonyl addition of organolithium and Grignard reagents to 3-acylisoxazolines , 1985 .
[57] K. Tomioka,et al. Asymmetric alkylation of .alpha.-alkyl .beta.-keto esters , 1984 .
[58] G. Thyagarajan,et al. Michaelis-Arbuzov rearrangement , 1981 .