Hubbry Logo
StereoselectivityStereoselectivityMain
Open search
Stereoselectivity
Community hub
Stereoselectivity
logo
7 pages, 0 posts
0 subscribers
Be the first to start a discussion here.
Be the first to start a discussion here.
Contribute something
Stereoselectivity
Stereoselectivity
Stereoselectivity
View on Wikipedia
from Wikipedia

In chemistry, stereoselectivity[1] is the property of a chemical reaction in which a single reactant forms an unequal mixture of stereoisomers during a non-stereospecific creation of a new stereocenter or during a non-stereospecific transformation of a pre-existing one.[2] The selectivity arises from differences in steric and electronic effects in the mechanistic pathways leading to the different products. Stereoselectivity can vary in degree but it can never be total since the activation energy difference between the two pathways is finite: both products are at least possible and merely differ in amount. However, in favorable cases, the minor stereoisomer may not be detectable by the analytic methods used.

An enantioselective reaction is one in which one enantiomer is formed in preference to the other, in a reaction that creates an optically active product from an achiral starting material, using either a chiral catalyst, an enzyme or a chiral reagent. The degree of selectivity is measured by the enantiomeric excess. An important variant is kinetic resolution, in which a pre-existing chiral center undergoes reaction with a chiral catalyst, an enzyme or a chiral reagent such that one enantiomer reacts faster than the other and leaves behind the less reactive enantiomer, or in which a pre-existing chiral center influences the reactivity of a reaction center elsewhere in the same molecule.

A diastereoselective reaction is one in which one diastereomer is formed in preference to another (or in which a subset of all possible diastereomers dominates the product mixture), establishing a preferred relative stereochemistry. In this case, either two or more chiral centers are formed at once such that one relative stereochemistry is favored,[3] or a pre-existing chiral center (which needs not be optically pure) biases the stereochemical outcome during the creation of another. The degree of relative selectivity is measured by the diastereomeric excess.

Stereoconvergence can be considered an opposite of stereospecificity, when the reaction of two different stereoisomers yield a single product stereoisomer.

The quality of stereoselectivity is concerned solely with the products, and their stereochemistry. Of a number of possible stereoisomeric products, the reaction selects one or two to be formed.

Stereomutation is a general term for the conversion of one stereoisomer into another. For example, racemization (as in SN1 reactions), epimerization (as in interconversion of D-glucose and D-mannose in Lobry de Bruyn–Van Ekenstein transformation), or asymmetric transformation (conversion of a racemate into a pure enantiomer or into a mixture in which one enantiomer is present in excess, or of a diastereoisomeric mixture into a single diastereoisomer or into a mixture in which one diastereoisomer predominates).[4]

Examples

[edit]

An example of modest stereoselectivity is the dehydrohalogenation of 2-iodobutane which yields 60% trans-2-butene and 20% cis-2-butene.[5] Since alkene geometric isomers are also classified as diastereomers, this reaction would also be called diastereoselective.

Stereoselective dehalogenation

Cram's rule predicts the major diastereomer resulting from the diastereoselective nucleophilic addition to a carbonyl group next to a chiral center. The chiral center need not be optically pure, as the relative stereochemistry will be the same for both enantiomers. In the example below the (S)-aldehyde reacts with a thiazole to form the (S,S) diastereomer but only a small amount of the (S,R) diastereomer:[6]

Stereoselective addition of a thiazole to an aldehyde

The Sharpless epoxidation is an example of an enantioselective process, in which an achiral allylic alcohol substrate is transformed into an optically active epoxyalcohol. In the case of chiral allylic alcohols, kinetic resolution results. Another example is Sharpless asymmetric dihydroxylation. In the example below the achiral alkene yields only one of the possible 4 stereoisomers.[7]

Stereoselective Sharpless oxidation

With a stereogenic center next to the carbocation the substitution can be stereoselective in inter- [8] and intramolecular [9][10] reactions. In the reaction depicted below the nucleophile (furan) can approach the carbocation formed from the least shielded side away from the bulky t-butyl group resulting in high facial diastereoselectivity:

Stereoselective reaction with carbocation Bach 2005

Stereoselective biosynthesis

[edit]

Pinoresinol biosynthesis involved a protein called a dirigent protein. The first dirigent protein was discovered in Forsythia intermedia. This protein has been found to direct the stereoselective biosynthesis of (+)-pinoresinol from coniferyl alcohol monomers.[11] Recently, a second, enantiocomplementary dirigent protein was identified in Arabidopsis thaliana, which directs enantioselective synthesis of (−)-pinoresinol.[12]

Reaction of monolignol radicals in the presence of dirigent protein to form (+)-pinoresinol

See also

[edit]

Notes and references

[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia

Stereoselectivity

View on Grokipedia
from Grokipedia
Stereoselectivity is the preferential formation in a of one stereoisomer over another. This phenomenon arises due to differences in the transition states leading to different stereoisomeric products, often influenced by steric, electronic, or conformational factors. When the stereoisomers are enantiomers, the selectivity is termed enantioselectivity and is quantified by enantiomeric excess (ee); for diastereomers, it is diastereoselectivity, measured by diastereomeric excess (de). In , stereoselectivity is distinguished from , where the latter refers to reactions in which stereoisomeric starting materials yield stereoisomerically related products, such that the product's stereochemistry is directly determined by the reactant's configuration. All stereospecific reactions are inherently stereoselective, but stereoselective reactions may produce mixtures of stereoisomers with one predominating, rather than a single product exclusively. Common examples include syn or anti addition to alkenes, such as the syn using , which favors one face of the over the other. Stereoselectivity plays a pivotal role in , enabling the controlled construction of complex molecules with defined three-dimensional architectures essential for . In pharmaceutical development, stereoisomers of drugs can exhibit dramatically different pharmacological profiles—one enantiomer may be therapeutic while the other is inactive or toxic—necessitating stereoselective methods to produce enantiomerically pure compounds. Advances in asymmetric , such as those using chiral ligands or enzymes, have revolutionized stereoselective synthesis, improving efficiency and sustainability in producing and natural products.

Definitions and Principles

Definition

Stereoselectivity refers to the preferential formation in a of one stereoisomer over another when multiple stereoisomers are possible from the same reactant and reaction pathway. This property arises because reactions can favor certain spatial arrangements of atoms due to differences in energies, leading to an unequal mixture where the preferred stereoisomer predominates. Stereoisomers are molecules with identical molecular formulas and connectivity of atoms but differing in the three-dimensional arrangement of those atoms. Key types include enantiomers, which are nonsuperimposable mirror images of each other and exhibit identical physical properties except for , and diastereomers, which are stereoisomers that are not mirror images and often differ in physical properties such as melting points and solubilities. The importance of stereoselectivity in chemistry lies in its role in efficiently producing chiral molecules, which are critical for applications in and synthesis, as the specific often dictates and pharmacological efficacy. For instance, in pharmaceuticals, the wrong stereoisomer can lead to reduced potency or adverse effects, underscoring the need for selective reactions to isolate bioactive forms. Quantitative assessment of stereoselectivity uses metrics like enantiomeric excess (ee) for reactions involving and diastereomeric excess (de) for . Enantiomeric excess is defined as ee = |(% major ) - (% minor )|, providing a measure of chiral purity; for example, a mixture with 85% (R)- and 15% (S)- yields ee = 70%. Diastereomeric excess follows an analogous calculation, de = |(% major ) - (% minor )|, to evaluate selectivity between .

Distinction from Stereospecificity

Stereospecificity describes a in which stereoisomerically pure reactants yield correspondingly distinct stereoisomeric products, such that different stereoisomers of the starting material produce different stereoisomers of the product. This contrasts with stereoselectivity, which, as defined earlier, involves the preferential but not necessarily exclusive formation of one stereoisomer from a given reactant. In essence, stereospecific reactions exhibit complete control over product stereochemistry based on reactant configuration, rendering them a subset of stereoselective processes; however, many stereoselective reactions lack this strict dependency and may produce mixtures of stereoisomers. A classic illustration of stereospecificity is the bimolecular nucleophilic substitution () reaction, where the reactant undergoes complete inversion of configuration at the reaction center, as established through kinetic and stereochemical studies. Similarly, in bimolecular elimination (E2) reactions, the anti-periplanar requirement for the departing groups ensures that the geometry of the resulting directly reflects the relative of the starting material, producing Z or E products predictably from diastereomeric precursors. The foundational concepts distinguishing these reaction behaviors emerged from Christopher Ingold's mechanistic investigations into substitution and elimination processes during , particularly his elucidation of concerted pathways that impose rigid constraints. In non- additions, such as certain electrophilic additions to alkenes, the process may favor one stereoisomer due to steric or electronic factors but does not mandate a unique outcome tied to any inherent reactant stereochemistry, often yielding mixtures rather than pure stereoisomers. This distinction is crucial for understanding reaction design, as stereospecificity guarantees predictability in stereochemical transfer, whereas stereoselectivity offers tunable preference without absolute certainty.

Types

Enantioselectivity

Enantioselectivity refers to the preferential formation in a of one over the other when the stereoisomers involved are enantiomers. This phenomenon is central to asymmetric synthesis, where reactions starting from achiral substrates produce a chiral product with a bias toward one mirror-image form, typically requiring the use of chiral catalysts, , or to induce the selectivity. A key concept in enantioselectivity is chiral induction, whereby a chiral element in the reaction environment differentiates the two enantiotopic faces of a prochiral substrate, favoring the formation of one over the other. The outcome is measured in terms of , assigned using the Cahn-Ingold-Prelog (CIP) priority rules to designate the as or ; for instance, a highly enantioselective reaction might yield predominantly the ()-enantiomer if the clockwise arrangement of substituents (with the lowest priority group pointing away) predominates. The degree of enantioselectivity is quantified by enantiomeric excess (), defined as ee = \frac{|[major] - [minor]|}{[major] + [minor]} \times 100%, where [major] and [minor] represent the concentrations of the predominant and subordinate enantiomers, respectively. This metric directly reflects the purity of the chiral product; for example, an ee of 90% corresponds to a 95:5 molar of the major to minor enantiomer, indicating strong but incomplete selectivity. Theoretically, enantioselectivity arises from the free energy difference (ΔΔG‡) between the transition states leading to each ; a larger ΔΔG‡ results in greater differentiation, as the lower-energy pathway dominates kinetically, while even small differences (on the order of 1-2 kcal/mol) can yield useful levels of selectivity in practice.

Diastereoselectivity

Diastereoselectivity describes the preferential formation of one over another in chemical reactions where the substrate already contains one or more chiral centers, resulting in products that are stereoisomers but not mirror images of each other. This type of selectivity arises because possess different physical and chemical properties due to their non-superimposable, non-mirror-image configurations at multiple stereocenters. In reactions involving facial selectivity, such as nucleophilic additions to chiral carbonyl compounds, qualitative models guide the prediction of preferred diastereomer formation. Cram's rule posits that the nucleophile approaches the carbonyl from the less hindered face in a conformation where the largest substituent adjacent to the chiral center is positioned anti to the incoming group, minimizing steric interactions. Complementing this non-chelation model, chelation control occurs when a metal coordinates simultaneously to the carbonyl oxygen and a nearby heteroatom (such as oxygen or ) in the substrate, rigidifying the conformation and directing the nucleophile to the opposite face for enhanced selectivity. Diastereoselectivity is measured using the diastereomeric excess (de), defined as the percentage difference in the amounts of the two diastereomers formed: de=∣[D1]−[D2]∣[D1]+[D2]×100%\text{de} = \frac{|[\text{D}_1] - [\text{D}_2]|}{[\text{D}_1] + [\text{D}_2]} \times 100\% where [D1][\text{D}_1] and [D2][\text{D}_2] represent the concentrations or mole fractions of the major and minor diastereomers, respectively. This metric is analogous to enantiomeric excess but applies to diastereomers; for instance, a 10:1 ratio corresponds to a de of approximately 82%, indicating the major diastereomer constitutes 91% of the product mixture. Compared to enantioselectivity, which distinguishes between enantiomers in a chiral environment and often yields moderate levels due to their energetic equivalence, diastereoselectivity is typically higher because the existing chiral centers in the substrate create distinct energy differences between transition states leading to diastereomeric products. Enantioselectivity represents a related but distinct aspect of stereoselectivity focused on mirror-image products.

Mechanisms and Control

Kinetic vs. Thermodynamic Control

In stereoselective reactions, kinetic control determines the outcome when the reaction proceeds irreversibly, favoring the stereoisomer formed through the transition state with the lower activation energy. The selectivity arises from the difference in activation free energies, denoted as ΔΔG‡\Delta \Delta G^\ddagger, between competing pathways, where a smaller ΔΔG‡\Delta \Delta G^\ddagger leads to higher stereoselectivity by exponentially favoring the lower-energy route according to the Eyring equation. Low temperatures enhance this regime by minimizing thermal energy available for alternative pathways, ensuring the reaction captures the kinetically preferred product before significant side reactions occur. Under thermodynamic control, stereoselectivity is governed by the relative stabilities of the stereoisomeric products, allowing the most stable to predominate at equilibrium. This occurs in reversible reactions where products and intermediates interconvert freely, driven by differences in their Gibbs free energies (ΔG\Delta G), with the lower-energy stereoisomer accumulating over time. Higher temperatures promote this control by increasing the rate of equilibration, enabling the system to overcome barriers and reach the global energy minimum. Catalysts can influence this regime by lowering reversal barriers without altering product stabilities, thus facilitating thermodynamic resolution. Qualitatively, energy diagrams for these regimes differ markedly: in kinetic control, the profile emphasizes the heights of transition state barriers from reactants, where the path with the shallowest barrier dictates selectivity, often leading to metastable products. In contrast, thermodynamic control focuses on the depths of product energy wells relative to each other, with transition states between products being surmountable under equilibrating conditions, resulting in the deepest well (most stable stereoisomer) prevailing. The switch between regimes is primarily triggered by reaction reversibility—irreversible for kinetic, reversible for thermodynamic—modulated by and catalyst design to tune barrier accessibility.

Factors Influencing Selectivity

Steric factors significantly dictate the stereochemical outcome of reactions by imposing spatial constraints that favor transition states with minimal non-bonded repulsions. In nucleophilic additions to aldehydes or ketones bearing an α-, bulkier substituents on the stereocenter rotate to an anti position relative to the incoming , as described by the Felkin-Anh model, thereby directing approach from the less hindered face. This model, supported by computational analyses, highlights how increasing steric bulk enhances selectivity by widening the energy gap between competing conformers. Electronic factors complement steric influences by modulating energies through polarization and orbital interactions. Polar substituents can stabilize specific geometries via electrostatic effects, while stereoelectronic interactions, such as from adjacent σ-bonds, align to lower the barrier for the preferred pathway in additions or eliminations. For example, electron-withdrawing groups may polarize the substrate to favor nucleophilic attack from one face, thereby controlling diastereoselectivity in conjugate additions. Chiral auxiliaries and catalysts impose on otherwise achiral substrates or , amplifying differences in free energies (ΔΔG‡) to drive high selectivity. Chiral auxiliaries, like the Evans oxazolidin-2-one, are covalently attached to create a rigid, shielded environment that directs geometry in aldol reactions, ensuring facial discrimination through or steric blocking. Similarly, chiral catalysts, such as BINAP-rhodium complexes in , form enantioselective binding pockets that differentiate enantiotopic faces via non-covalent interactions, enabling efficient enantiocontrol across diverse substrates. Solvent and temperature further tune selectivity by affecting solvation and population dynamics. Polar solvents stabilize charged or polar s, often enhancing electronic control and inverting selectivity compared to nonpolar media, as seen in Diels-Alder reactions where protic solvents promote endo products through hydrogen bonding. Temperature modulates the kinetic regime, with lower values favoring the thermodynamically less stable but kinetically preferred stereoisomer by limiting access to higher-energy pathways, a principle applied in cryogenic conditions for aldol additions to maximize diastereoselectivity.

Applications and Examples

In Synthetic Organic Chemistry

Stereoselectivity plays a pivotal role in synthetic by enabling the efficient construction of chiral molecules with precise three-dimensional architectures, which is essential for the of pharmaceuticals and products. Through the design of chiral catalysts and , chemists can control the stereochemical outcome of reactions, often achieving high enantiomeric excess () or diastereomeric excess (de) to minimize the need for laborious separations. This control is particularly valuable in multi-step syntheses where a single stereogenic center can dictate the and safety of the final compound. One landmark example of stereoselectivity in synthesis is the Sharpless asymmetric epoxidation, which provides enantioselective access to epoxy alcohols from allylic alcohols. This reaction employs a chiral titanium catalyst formed from titanium tetraisopropoxide and , along with tert-butyl hydroperoxide as the oxidant, to deliver the with predictable facial selectivity based on the tartrate . For kinetic resolution of racemic secondary allylic alcohols, the method selectively epoxidizes one , allowing isolation of the unreacted alcohol in high (often >95%) and the epoxy alcohol product in complementary high , thus enabling the preparation of both s from a racemic starting material. This enantioselective process exemplifies kinetic control in asymmetric synthesis, with applications in building complex chiral scaffolds. In chemistry, the Diels-Alder reaction demonstrates diastereoselectivity when using chiral dienophiles, guided by the endo rule that favors the where the dienophile's substituents align endo to the for enhanced orbital overlap. Seminal work using chiral N-acyloxazolidinone auxiliaries attached to α,β-unsaturated acyl groups as dienophiles with yields cycloadducts with high diastereoselectivity (de >90%), where the auxiliary dictates facial approach and the endo geometry predominates. This approach allows for the stereocontrolled formation of up to four new stereocenters in a single step, facilitating the synthesis of polycyclic frameworks with defined relative . Enantioselective hydrogenation of alkenes represents another cornerstone, where variants of (RhCl(PPh₃)₃) modified with chiral bisphosphine ligands enable precise stereocontrol. The use of (R,R)-DIPAMP as a ligand in complexes achieves high enantioselectivity in the reduction of enamides, such as those derived from α-acetamidoacrylic acids, yielding precursors with ee up to 94%. This method's has made it industrially viable for producing enantiopure building blocks. Advances in stereoselective synthesis have profoundly impacted pharmaceutical development, particularly in the of statins like and , where stereocontrol at key hydroxyl-bearing centers enhances potency and reduces side effects. Highly stereoselective hydrogenations serve as critical steps in these routes, ensuring the correct configuration at multiple chiral centers to mimic the natural substrate for inhibition.

In Biosynthesis

Enzymes serve as chiral catalysts in biosynthesis, enforcing stereoselectivity through their three-dimensional active sites that provide pocket-like environments for substrate binding, akin to the lock-and-key model proposed by Emil Fischer, where the enzyme's structure complements the substrate's geometry to favor one stereoisomer over others. This selectivity arises from precise steric and electronic interactions within the enzyme's chiral pocket, ensuring high fidelity in the formation of stereocenters during natural product assembly. In biological systems, such enzymatic control minimizes the production of inactive or deleterious stereoisomers, directing metabolic pathways toward bioactive molecules. A prominent example of enzymatic stereoselectivity occurs in biosynthesis, particularly the cyclization of to form steroids. epoxide undergoes a stereoselective polycyclization catalyzed by oxidosqualene cyclase (OSC), which guides the substrate through a series of rearrangements to yield with precise at multiple chiral centers, essential for subsequent production. This process exemplifies how enzymes like OSC achieve near-perfect stereocontrol by stabilizing specific transition states within their active sites, preventing alternative cyclization pathways. In synthesis, diastereoselective reductions are mediated by ketoreductase (KR) domains within modular polyketide synthases (PKSs), which convert β-ketoacyl intermediates to hydroxyacyl units with defined . For instance, in the of actinorhodin, the actKR domain performs a regio- and stereoselective reduction at the C9 carbonyl, producing the (R)-hydroxy configuration through hydride transfer from NADPH, controlled by the KR's Rossmann fold and residues. These KR domains classify into subtypes (A, B) that dictate syn or anti formation, enabling the diversity of polyketide natural products like antibiotics. From an evolutionary perspective, stereoselectivity in biosynthesis ensures the bioactivity of biomolecules by favoring configurations compatible with physiological targets. The universal adoption of L-amino acids in proteins, rather than D-enantiomers, likely originated from early chiral biases in prebiotic chemistry and RNA-world scenarios, where L-amino acids enhanced folding stability and receptor interactions, conferring survival advantages. This homochirality extends to other biopolymers, such as D-sugars in DNA/RNA, underscoring how stereoselective enzymatic machinery evolved to maintain functional specificity and avoid metabolic interference from mirror-image molecules. Recent advances in biocatalytic engineering, post-2020, have leveraged computational design and to enhance enzymatic stereoselectivity for biotech applications. For example, learning-guided of amidases has improved enantioselectivity ratios from 10:1 to over 100:1 in , enabling scalable production of chiral intermediates for pharmaceuticals. Similarly, semi-rational of ketoreductases has broadened substrate scope while preserving diastereoselectivity, facilitating greener synthesis routes in industrial biocatalysis. In 2025, biocatalytic dynamic kinetic resolution has been applied to synthesize enantioenriched atropisomers from achiral precursors, achieving high enantioselectivity in the formation of axially chiral biaryls.

References

  1. https://goldbook.iupac.org/terms/view/S05991
  2. https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Supplemental_Modules_%28Organic_Chemistry%29/Alkenes/Reactivity_of_Alkenes/Stereoselectivity_in_Addition_Reactions_to_Double_Bonds
  3. https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Supplemental_Modules_(Organic_Chemistry)/Chirality/Stereoisomers
  4. https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Supplemental_Modules_(Organic_Chemistry)/Chirality/Chirality_and_Stereoisomers
  5. https://pmc.ncbi.nlm.nih.gov/articles/PMC5762452/
  6. https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Map%3A_Essential_Organic_Chemistry_(Bruice)/06%3A_Isomers_and_Stereochemistry/5.10%3A_Enantiomeric_Excess
  7. https://www2.chemistry.msu.edu/faculty/reusch/virttxtjml/sterslct.htm
  8. https://goldbook.iupac.org/terms/view/S05994
  9. https://pubs.rsc.org/en/content/articlelanding/1937/jr/jr9370001252
  10. https://pubs.acs.org/doi/10.1021/cr030693c
  11. https://pubs.acs.org/doi/10.1021/acs.chemrev.2c00724
  12. https://ursula.chem.yale.edu/~chem220/chem220js/STUDYAIDS/isomers/RSfolder/RS.html
  13. https://pmc.ncbi.nlm.nih.gov/articles/PMC2536600/
  14. http://www.chem.ucla.edu/~harding/IGOC/D/diastereoselective.html
  15. https://community.wvu.edu/~josbour1/pages/Fall2018/531_Files/Stereospecificity%2520and%2520Stereoselectivity.pdf
  16. https://chemistry.wwu.edu/files/2020-04/ONeil_425bText%2520Organic%2520Reactions.pdf
  17. https://quod.lib.umich.edu/cgi/p/pod/dod-idx/diastereoselective-synthesis-of-tertiary-alcohols-by-n.pdf?c=ark%3Bidno=5550190.0007.605
  18. https://www2.chemistry.msu.edu/courses/cem852/SS16/handouts/Mukaiyama_aldol_Rev.CR99.pdf
  19. https://www2.chemistry.msu.edu/faculty/reusch/OrgTxtBook/sterslct.htm
  20. https://www.saskoer.ca/intro-organic-chemistry/chapter/8-4/
  21. https://www.dalalinstitute.com/wp-content/uploads/Books/A-Textbook-of-Organic-Chemistry-Volume-1/ATOOCV1-3-4-Kinetic-and-Thermodynamic-Control.pdf
  22. https://www.imperial.ac.uk/media/imperial-college/research-centres-and-groups/spivey-group/teaching/org3stereoelectronics/1617-CHEM60001-Stereoelectronics-3---Kin-vs-Thermo-Control.pdf
  23. https://www.beilstein-institut.de/download/667/clayden.pdf
  24. https://www.bcp.fu-berlin.de/en/chemie/chemie/forschung/OrgChem/tzschucke/teaching/Stereochemie/NouvJChim1977_61-Anh_Eisenstein_Felkin.pdf
  25. https://onlinelibrary.wiley.com/doi/full/10.1002/anie.201700616
  26. https://www.researchgate.net/profile/David-Evans-85/publication/237625776_Chiral_Auxiliaries_in_Asymmetric_Synthesis/links/543bbe610cf204cab1db23b8/Chiral-Auxiliaries-in-Asymmetric-Synthesis.pdf
  27. https://ethz.ch/content/dam/ethz/special-interest/chab/organic-chemistry/bode-group-dam/documents/open-source-lecture-notes/key-concepts-in-stereoselective-synthesis-2015.pdf
  28. https://pubs.rsc.org/en/content/articlepdf/2009/cs/b802815j
  29. https://pubs.acs.org/doi/10.1021/ja00538a077
  30. https://pubs.acs.org/doi/10.1021/ja00410a053
  31. https://pubs.acs.org/doi/10.1021/ja00212a037
  32. https://pubs.acs.org/doi/10.1021/ja00842a058
  33. https://onlinelibrary.wiley.com/doi/10.1002/chir.20782
  34. https://wires.onlinelibrary.wiley.com/doi/10.1002/wcms.1403
  35. https://pubs.rsc.org/en/content/articlehtml/2021/cb/d1cb00080b
  36. https://pubs.acs.org/doi/10.1021/cr040623l
  37. https://pmc.ncbi.nlm.nih.gov/articles/PMC11165016/
  38. https://pubs.acs.org/doi/10.1021/jacsau.2c00086
  39. https://pmc.ncbi.nlm.nih.gov/articles/PMC4775309/
  40. https://pmc.ncbi.nlm.nih.gov/articles/PMC10851380/
  41. https://www.mdpi.com/2073-8994/13/12/2277
  42. https://www.nature.com/articles/s41467-024-53048-0
  43. https://pmc.ncbi.nlm.nih.gov/articles/PMC9355150/
  44. https://www.nature.com/articles/s41586-025-09738-w
Add your contribution
Related Hubs
Contribute something
User Avatar
No comments yet.