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A asymmetric

J. D. Morrison, A., Asymmetric Synthesis,John Wiley Sons, Inc., New York, a continuing series. [Pg.183]

Sstig, a. branched, branchy knotted, gnarled. Astronom, m. astronomer. astroDomisch, a. astronomical, astrophysikalisch, a. astrophysical. asymmetrisch, a. asymmetric, asymmetrical, asymptotisch, a. asymptotic, asynchron, a. asynchronous, aszendent, a. (Mtn.) primary. [Pg.36]

Again, we are dealing with planted C-H trees with n vertices of degree 4. We restrict our attention to topologically different ones with exactly a asymmetric points let denote their number. Obviously, the relation... [Pg.43]

The principal node K is not an asymmetric point in this case the three principal branches are not all different and they have a total of a asymmetric vertices. [Pg.44]

Inequality (3.12) ensues from the well-known fact that a given structure which contains a asymmetric carbon atoms gives rise to 2 in general distinct, stereoisomers and in some exceptional cases to fewer than 2 stereoisomers. Nevertheless, the purely analytical deduction of inequality (3.12) from (7) and (2.22) corroborates the observation. The exception, that is the case in which there are fewer than 2 stereoisomers in the presence of a asymmetric carbon atoms, involves compensation of asymmetries. The corollary of (3.12) indicates that compensation of asymmetries in cannot occur... [Pg.67]

For some excellent monographs and reviews that deal with catalytic asymmetric synthesis, see (a) Asymmetric Synthesis, Morrison, J. D., Ed., Academic Press New York, 1985, Vol. 5 (b) Bosnich, B. Asymmetric Catalysis, Martinus Nijhoff Dordrecht, 1986 ... [Pg.376]

Whiting A. Asymmetric Diels-Alder Reactions in Adv. Asymmetric Synth. 1996 126, Ed. Stephenson G. R., Pb. Chapman and Hall, London... [Pg.314]

Wu, D. Kofke, D. A., Asymmetric bias in free-energy perturbation measurements using two Hamiltonian-based models, Phys. Rev. E 2004, 70, 066702... [Pg.197]

Figure 8.17 The main experimental geometries [6] in molecular spintronics via Direct coupling (a) asymmetric, using a conducting tip and a planar substrate and (b) symmetric. Figure 8.17 The main experimental geometries [6] in molecular spintronics via Direct coupling (a) asymmetric, using a conducting tip and a planar substrate and (b) symmetric.
Wynberg, H. and Snaardijk, A.A., Asymmetric catalysis in carbon-phosphorus bond formation, Tetrahedron Lett., 5899, 1983. [Pg.99]

Figure 1.20 Comparison of densities as a function of generation for (A) asymmetrical branch cell in DenkewaIter-type dendrimers, (B) symmetrical branch cell in Tomalia-type dendrimers ([densities calculated from experimental hydrodynamic diameters and theoretical, D.A. Tomalia, M. Hall, D.M. Hedstrand, J. Am. Chem. Soc., 109,1601 (1987))... Figure 1.20 Comparison of densities as a function of generation for (A) asymmetrical branch cell in DenkewaIter-type dendrimers, (B) symmetrical branch cell in Tomalia-type dendrimers ([densities calculated from experimental hydrodynamic diameters and theoretical, D.A. Tomalia, M. Hall, D.M. Hedstrand, J. Am. Chem. Soc., 109,1601 (1987))...
Although relatively weak, it is this last interaction that is essential for determining chiral discrimination. The superior chiral recognition achieved when ref has an aromatic side chain (Table 10) suggests that 7r-cation interactions play an important role in the stereoselectivity. Evidence for such a rr-cation interaction is observed in the CID spectra of the dimeric [A Me° ref-H]and [A -Me -ref-H] diaster-eomers, in which one ligand is an aromatic amino acid, and is supported by ab initio calculations. When an L-aromatic amino acid, such as L-phenylalanine, is used as ref, these interactions are disrupted by the side group on the a-asymmetric carbon of the L-analyte, whereas the side-chain group in the D-analyte has little steric effect on... [Pg.208]

A Asymmetric Reduction of Phenyl Ring-containing Ketones 287... [Pg.287]

Figure 1. Cross-section of Type A asymmetric UF membrane from a Nuclepore... Figure 1. Cross-section of Type A asymmetric UF membrane from a Nuclepore...
Koskinen A, Asymmetric Synthesis of Natural Products, John Wiley and Sons, 1993. [Pg.9]

Halicholactone 214, a marine metabolite with lipoxygenase inhibitory activity, belongs to the family of oxylipins which all contain a lactone moiety substituted by a /ra r-disubstituted cyclopropane subunit. Stereoselective RCM for the formation of the nine-membered lactone core in 214 was the penultimate step (212 —> 213) in a asymmetric... [Pg.230]

Klabunovskii, E. 1., and Bedeyapin, A. A., Asymmetric Catalysis-Hydrogenation Metals" (in Russian). Nauk, Moscow, 1980. [Pg.271]

These can be prepared by a) asymmetric dihydroxylation of allylic chlorides followed by acetonide formation and elimination with BuLi b) catalytic asymmetric transfer hydrogenation and c) reduction of alkynones with chiral metal hydrides, (a) Marshall, J. A. Jiang, H. Tetrahedron Lett. 1998, 39, 1493 Yadav, J. S. Chander, M. C. Rao, C. S. Tetrahedron Lett. 1989, 30, 5455 (b) Matsumura, K. Hashiguchi,... [Pg.69]


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See also in sourсe #XX -- [ Pg.35 , Pg.37 , Pg.1287 ]




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A asymmetric hydrogenation

A asymmetric synthesis

A,p-Unsaturated imide asymmetric aldol reaction

A-Amino acids asymmetric aldol cyclizations

A-Amino acids asymmetric hydrogenation

A-Amino acids asymmetric synthesis

A-Amino acids by asymmetric

A-Hydroxy acids asymmetric hydrogenation

A-Hydroxyl-co-carboxyl asymmetric

A-Methylation asymmetric

A-amino acids asymmetrical hydrogenation

ASYMMETRIC REDUCTION IN A CHIRAL REACTION FIELD

Alcohols, Phenols and Carboxylic Acids as Asymmetric Organocatalysts

Aldehydes, a-alkoxy 1,2-asymmetric induction

Alkaloid Derivatives as Asymmetric Phase-transfer Catalysts

Asymmetric Aldol Reactions of a-Isocyanocarboxylates

Asymmetric Autocatalysis Utilizing Enantiomorphous Inorganic Crystals as an Initial Source of Chirality

Asymmetric Catalytic Hydrogenation of a-Acetamidocinnamic Acid Esters

Asymmetric Electrophilic a-Substitution of Lactones and Lactams

Asymmetric Hydrogenations of a-Keto Esters

Asymmetric Mannich, a-Aminoxylation, and Diels-Alder Reaction

Asymmetric Nucleophilic a-Aminoacylation

Asymmetric Organocatalysis Introducing a Thiourea Catalyst for the Petasis Reaction

Asymmetric Organosilane Reduction of a,-Unsaturated Ketones

Asymmetric Reactions - A Rich Reservoir

Asymmetric Sulfoxidation using Flavins as Catalysts

Asymmetric Synthesis of a-Substituted Sulfonamides and Sulfonates

Asymmetric Tops attached to a Rigid Frame

Asymmetric a-alkylation

Asymmetric a-alkylation aldehydes and ketones

Asymmetric a-alkylation reactions

Asymmetric a-alumina

Asymmetric a-amino anions

Asymmetric a-aminoxylation

Asymmetric a-functionalization

Asymmetric a-sulfenylation

Asymmetric aza Diels-Alder reactions synthesis of tetrahydroquinoline derivatives using a chiral lanthanide Lewis acid as catalyst

Asymmetric hydrogenation of a-acetamido cinnamic acid

Asymmetric hydrogenation of vinylphosphonic acids carrying a phenyl substituent at

Asymmetric oxidation of a,P-unsaturated sulfides

Asymmetric reduction of a prochiral ketone (chloroacetophenone)

Asymmetric reduction of a-acetamido cinnamic acid

Asymmetric reduction of a-keto esters

Asymmetric reduction of chloroacetophenone using a sulfoximine catalyst

Asymmetric syntheses of a-amino

Asymmetric syntheses of a-amino acids

Asymmetric synthesis of talaromycin A and

Asymmetrical synthesis of a-amino acids

Binaphthyl-derived Cyclic Amines and Their Salts as Asymmetric Organocatalysts

Chiral Amines as Catalysts in Asymmetric Mannich Reactions

Cinchona Alkaloids as Chiral Ligands in Asymmetric Oxidations

Cumulative photovoltage in an asymmetrical stack of D A interfaces

Discrimination of Cryptochirality in a Saturated Quaternary Hydrocarbon by Asymmetric Autocatalysis

Ethers, Taddol, Nobin and Metal(salen) Complexes as Chiral Phase-Transfer Catalysts for Asymmetric Synthesis

Glycinate Schiff Base Asymmetric Synthesis of a-Amino Acids

Glyoxylic acid, a-naphthylmenthyl ester asymmetric hydrogenation

Gold and Silver-Catalyzed Asymmetric Aldol Reactions of a-Isocyanocarboxylates

Guanidines as Asymmetric Organocatalysts

Hydroxyproline Derivatives as Asymmetric Organocatalysts

Imidazoles and Pyridines as Asymmetric Organocatalysts

Ketones, a-hydroxy asymmetric synthesis

Ketones, a-hydroxy intramolecular asymmetric

N-Heterocyclic Carbenes as Asymmetric Organocatalysts

Other 2-Substituted Pyrrolidines as Asymmetric Organocatalysts

Other Amino Acids as Asymmetric Organocatalysts

Oxazaborolidines as Asymmetric Inducers for the Reduction of Ketones and Ketimines

Oxazolines as ligands in asymmetric synthesis x-ray crystal structure

Peptides as Asymmetric Organocatalysts

Prolinamides as Asymmetric Organocatalysts

Proline as an Asymmetric Organocatalyst

Prolinol Silyl Ethers as Asymmetric Organocatalysts

Prolinols and Their Carbon Ethers as Asymmetric Organocatalysts

Ratchet Motion of a Droplet on Asymmetric Electrodes

Rotation of an Asymmetric Top restricted by a Complex Potential Barrier

Sulfoximines as Ligands in Asymmetric Metal Catalysis

The Conjugate Addition Reaction a Very Convenient Platform for Asymmetric Organocatalysis

Ureas and Thioureas as Asymmetric Organocatalysts

Use of Nobin and Related Species as Asymmetric Phase-Transfer Catalysts

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