DOSEN PROFIL LENGKAP

In stereochemistry, prochiral molecules are those that can be converted from achiral to chiral in a single step, such as changing one atom. An achiral...

Desymmetrization is a chemical reaction that converts prochiral substrates into chiral products. Desymmetrisations are so pervasive that they are rarely...

and by Wrinch that were widely discussed in the 1940s. The concept of prochirality is necessary for understanding some aspects of enzyme stereospecificity...

groups that can be prochiral and readily susceptible to oxidation include certain alkenes and thioethers. Challenging but pervasive prochiral substrates are...

are less than 100% pure, typically 95%. Although achiral, glycerol is prochiral with respect to reactions of one of the two primary alcohols. Thus, in...

aldol condensations, oxidations, etc. It is the simplest aldehyde with a prochiral methylene such that α-functionalized derivatives (CH3CH(X)CHO) are chiral...

metal-propylene complexes, which are intermediates in these processes. Propylene is prochiral, meaning that binding of a reagent (such as a metal electrophile) to the...

position of an enol is substituted (i.e., not a methyl ketone), then it is prochiral, forming a new stereocenter when in keto form. Conversely, enolization...

coarctate transition state. Chiral epoxides are produced by epoxidation of prochiral alkenes. When the catalyst is chiral or the alkene is chiral, then asymmetric...

Corey–Bakshi–Shibata (CBS) reduction, is a chemical reaction in which a prochiral ketone is enantioselectively reduced to produce the corresponding chiral...

will give the (R)-enantiomer. However, adding a chemical group to the prochiral center from the Re-face will not always lead to an (S)-stereocenter, as...

below. Consequently, when the Grignard reagent adds to an aldehyde or a prochiral ketone, the Felkin-Anh model or Cram's Rule can usually predict which...

transfer it from below. Since the C4 carbon that accepts the hydrogen is prochiral, this can be exploited in enzyme kinetics to give information about the...

which means that they can be used for the enantioselective hydrolysis prochiral diesters. Several procedures have been reported for applications in the...

liquid is the methyl ester of pyruvic acid. It has attracted interest as a prochiral precursor to alanine and lactic acid. It is prepared by esterification...

over a copper chromite catalyst: C6H5C(O)CH3 + H2 → C6H5CH(OH)CH3 Being prochiral, acetophenone is also a popular test substrate for asymmetric hydrogenation...

used to establish sp3-stereocenters from allylic diazenes containing prochiral stereocenters. The influence of the alkoxy stereocenter results in diastereoselective...

stereoselectivity of this reaction was further investigated through study of prochiral methylene hydrogen discrimination. This is due to the extra chiral center...

require any transition metals. Asymmetric synthesis is possible from prochiral electrophiles. The product's dense functionalization enables many further...

is a subset of asymmetric catalytic oxidations. Epoxidations convert prochiral (and other) alkenes to chiral epoxide derivatives. In asymmetric epoxidation...

Baeyer–Villiger oxidations. The first reported instance of one such oxidation of a prochiral ketone used dioxygen as the oxidant with a copper catalyst. Other catalysts...

probe of the stereochemistry of reactions involving alkenes because it is prochiral and the two sp2-carbon atoms differ. The regioselectivity and stereoselectivity...

Greg; Simpkins, Nigel S. (1990-01-01). "Asymmetric deprotonation of prochiral ketones using chiral lithium amide bases". Tetrahedron. 46 (2): 523–544...

developed also: HOCH2CH(OH)CH2OH + O2 → HOCH2CH(OH)CO2H + H2O As glycerol is prochiral, the oxidation of the two terminal alcohol groups gives distinct enantiomers...

catalysts are also used in asymmetric synthesis by the hydrogenation of prochiral substrates. An early demonstration of this approach was the Rh-catalyzed...

Bischler–Napieralski reaction. Electrophilic aromatic substitutions with prochiral carbon electrophiles have been adapted for asymmetric synthesis by switching...

a multifunctional molecule that exhibits diverse reactivity. It is a prochiral dienophile. It is a Michael acceptor. Addition of methylmagnesium chloride...

determine if a person is suffering shock si, a chemical descriptor; See prochirality Silicon, symbol Si, a chemical element Disulfur diiodide, empirical formula...

electrophile in organic synthesis. In addition reactions acetaldehyde is prochiral. It is used primarily as a source of the "CH3C+H(OH)" synthon in aldol...

in an aldol condensation reaction. The citrate product is said to be prochiral. This conversion begins with the negatively charged carboxylate side chain...

the preparation of certain cyclopropanes in the Kulinkovich reaction. Prochiral thioethers are oxidized enantioselectively using a catalyst derived from...

usually prepared by the acylation of benzene using valeryl chloride. Being prochiral, valerophenone undergoes enantioselective hydrogenation to the corresponding...

cyanoborohydride. Since imines derived from unsymmetrical ketones are prochiral, their reduction defines a route to chiral amines. Unhindered aldimines...

epoxidation, which is renowned for its ability to enantioselectively transform prochiral alkenes into epoxides. Before its development, catalysts for the asymmetric...

aluminium based Meerwein–Ponndorf–Verley reduction can be performed on prochiral ketones leading to chiral alcohols. The three main ways to achieve the...

then oxidize further to dimethyl sulfone. Unsymmetrical sulfides are prochiral — their oxidation gives chiral sulfoxides. The process can be performed...

Enantioselective ketone reductions convert prochiral ketones into chiral, non-racemic alcohols and are used heavily for the synthesis of stereodefined...

imines. If the complex is chiral and non-racemic and the substrate is prochiral, an excess of a single enantiomer of a chiral product can result. Hydrogen...

than acetone itself. Unlike both of those ketones, trifluoroacetone is prochiral. Hydrogenation of trifluoroacetone over platinum catalyst gives trifluoroisopropanol...

pyridine compound is a better leaving group than a carboxylate ion. For prochiral cyclic anhydrides, the alcoholysis reaction can be conducted asymmetrically...

can be converted to a cyclic product in one step, in the same sense as prochiral Procyclic life stage, a life stage of the Trypanosoma parasite in African...

O-methylation gives the bis-lactim. A proton is then abstracted from the prochiral position on glycine with n-BuLi. The next step decides the stereoselectivity...

catalyst was reported in 2005 to provide isotactic polymerization of the prochiral propylene oxide PPG has many properties in common with polyethylene glycol...

C2-symmetric diphosphine. Its complexes have been applied to the reduction of prochiral olefins, ketones, and imines. Knowles et al. independently reported the...

multi-step synthesis in the construction of polycyclic natural products. It is prochiral. With strong bases, the positions 4 and 6 (the two CH2-groups of the carbonyl...

complex Enantioface exchange in the π-allyl complex Differentiation of prochiral nucleophile faces The favored method for enantiodiscrimination is largely...

"recognized" upon the formation of the enzyme-substrate complex. Thus a prochiral substrate may be transformed into an optically active product and both...

isomers. One of these isomers displays a helical twist and is therefore prochiral. The P and M enantiomers have been separated. Pentamantane has nine isomers...

proceed with high enantioselectivities when the starting material is prochiral: RR'C=O + Me2CHOH → RR'C*H−OH + Me2C=O where RR'C*H−OH is a chiral product...

to form a rhodium complex to catalyze asymmetric hydroformylation of prochiral olefins. It has been shown that high substrate concentrations as well...

→ Ni(CN)2L2 + H2 Ni(R)(CN)L2 + HCN → Ni(CN)2L2 + RH Most alkenes are prochiral, and their hydrocyanation generates chiral nitriles. Conventional hydrocyanation...

enantioselectivities. An enantioselective (80 to 92% ee) reduction of prochiral α,β-unsaturated esters uses Tol-BINAP complexes of copper in the presence...

dipolarophile—if the dipolarophile is more than mono-substituted (and prochiral), up to four new stereocenters can result in the product. Azomethine ylides...

whereby only one of two possible enantiomeric products are generated from a prochiral substrate, rely on electrophilic fluorination reagents. Illustrative of...

In 1981, Hirao and co-workers have found that asymmetric reduction of prochiral aromatic ketones with chiral amino alcohols and borane afforded the corresponding...

are known. These derivatives, also known as N-acylamino acrylates, are prochiral substrates for asymmetric hydrogenation. The 2001 Nobel Prize in Chemistry...

catalysis. Barbas' collaborator List also extended the reaction to asymmetric prochiral ketones: List and Notz also revealed that proline and 5,5-dimethyl...

chiral titanium complex (Figure 12) in asymmetric ene reactions involving prochiral glyoxylate esters. The catalyst is prepared in situ from (i-PrO)2TiX2...

are equivalent except that one is "pro-R" and the other "pro-S" (see Prochirality). At this point, the intermediate is rotated 180°. This rotation is referred...

biotin-streptavidin interaction. The formed ArM can catalyze the reduction of prochiral ketones. Taking advantages of protein evolvability, different mutants...

greater than the rate of beta-hydride elimination. Hydroformylation of prochiral alkenes creates new stereocenters. Using chiral phosphine ligands, the...

BM, Brennan MK (May 2006). "Palladium asymmetric allylic alkylation of prochiral nucleophiles: horsfiline". Organic Letters. 8 (10): 2027–30. doi:10.1021/ol060298j...

Synthesis of syn-α-Substituted β-Amino Ketones using Sulfinimines and Prochiral Weinreb Amide Enolates". Organic Letters. 9 (12): 2413–2416. doi:10.1021/ol0708166...

HIV reverse transcriptase inhibitor. Lithium acetylide is added to a prochiral ketone to yield a chiral alcohol product. The structure of the active...

explained in terms of steric interactions between the ligand and the prochiral substrate. Consideration of these interactions has led to the development...

afford a mixture of E- and Z- isomers (1:3 E/Z) in 89% yield. Although one prochiral center is present the product is racemic. Floresolide is an atropisomer...

oxazolidinones. Extensive work has been reported on asymmetric hydroxylation of prochiral enolates with camphorsulfonyloxaziridine derivatives, achieving moderate...

atropisomerism; the rigidity of the phosphene ligands can impart chirality on prochiral substrates with high fidelity, allowing for asymmetric hydrogenation....

diphosphines such as BINAP. Styrene or its simple derivatives are usually the prochiral substrate. Enantioselectivity tends to be lowered with ortho-substituents...

3-hexafluoropropane as a non-coordinating solvent. Fp-R compounds are prochiral, and studies have exploited the chiral derivatives CpFe(PPh3)(CO)acyl...

including protonation of carbanions, acylation and alkylation of achiral and prochiral nucleophiles, parallel kinetic resolution, and control of configuration...

them. The complexes were used for asymmetric homogenous hydrogenation of prochiral substrates, and the obtained results allowed elucidating the effects of...

Marinetti, Angela; Ricard, Louis; Mathey, Francois (January 1992). "Use of prochiral phosphaalkene complexes in the synthesis of optically active phosphines"...

can from a stereospecific carbon–carbon bond used in the synthesis of prochiral ketones which are important precursors in biofuel production. Hydrogenases...

different. They are neither diastereotopic or enantiotopic nor homotopic. Prochiral conformational analysis 300 MHz 1H-NMR spectrum of ethyl phenylalaninate...

been extensively studied. Unsymmetrical thioethers, e.g., SMeEt, are prochiral ligands, and their complexes are chiral. One example is [Ru(NH3)5(SMeEt)]2+...

alkenes to form substituted alkanes can be rendered enantioselective if prochiral alkenes are used. In these reactions, a chiral indenyl zirconium catalyst...