Wheel of Corey Reactions

Elias James Corey, an American organic chemist, won the Nobel prize in chemistry "for his development of the theory and methodology of organic synthesis", precisely, retrosynthetic analysis.


In retrosynthetic analysis, a synthon (coined by Corey) is a hypothetical unit within a target molecule that represents a potential starting material in the retroactive synthesis of that target molecule. Corey noted later that the "word synthon has now come to be used to mean synthetic building block rather than retrosynthetic fragmentation structures". The phrase did not feature prominently in Corey's book The Logic of Chemical Synthesis, as it was excluded in the index. When placed into a synthesis, an uncharged form is found commercially instead of forming and using the potentially quite unstable charged synthons.

There exists a number of name reactions that include Corey. The following wheel of organic reactions contains 16 such chemical reactions.


Wheel of Corey Reactions: Click/tap to enlarge the image

Substrate + (Reagent(s)) -> Product

  1. Ketones + (BH3*Ligand, 1 eq. CBS cat.) -> Chiral alcohols (CBS aka Corey-Itsuno reduction)
  2. Propargyl alcohols + (LAH or SMEAH) -> E-allylic alcohols by stereoselective reduction (Corey-Chan stereoselective alkene synthesis)
  3. Imines + (Me2S=CH2, DMSO) -> Aziridines (Corey-Chaykovsky aziridination)
  4. Ketones (or imines) + (R3R4C─S+R’R’’X─, base) -> Epoxides (or aziridines) (Corey-Chaykovsky aka Corey-Tschaikosky  aka Johnson-Corey-Chaykovsky epoxidation/reaction)
  5. Aldehydes + (1. CBr4, TPP 2. n-BuLi 3. H2O) -> Terminal alkynes (Corey-Fuchs aka Ramirez–Corey–Fuchs alkyne synthesis/homologation/reaction (1-C) via dibromoolefins)
  6. Benzylic (or α,β-unsat.) aldehydes + (MnO2, KCN, EtOH, rt) -> Alkyl esters (Corey-Gilman-Ganem oxidation)
  7. 10 (or 20) alcohols + (1. NCS, Me2S 2. Et3N) -> Aldehydes (or ketones) (via alkoxysulfonium salts) (Corey-Kim oxidation)
  8. Aldehydes (or ketones) + (1. R3R4CH─P(=O)(NR2)2, n-BuLi 2. H2O, Δ) -> Olefins (Corey-Kwiatkowski reaction)
  9. 1,1,1-trichloro-2-ketones + (1. HBCat, 0.1 CBS cat., DCM 2. HO─, N3─ 3. HO─ 4. H+ 5. Pd-C, H2) -> α-Amino acids (or other acyl derivatives) (enantioselective) (Corey-Link reaction)
  10. Hydroxyacids + (1. 2,2’-Dipyridyl disulfide, TPP, solvent, rt 2. Δ or Ag+) -> Lactones (via thioesters) (Corey-Nicolaou aka Corey-Nicolaou-Gerlach macrolactonization)
  11. Carbonyl derivatives + (R3Si─C─HR3 M+, acid or base) -> E- or Z- olefins via β-silylalkoxides (Corey-Peterson aka Peterson olefination)
  12. Alkyl (or aryl) halides + (R2CuLi) -> Alkanes (Corey-House aka Corey-Posner-Whitesides-House synthesis/coupling/reaction; Halide = Cl, Br, I, OMs or OTs)
  13. 10 (or 20) alkyl/aryl alcohols + (PDC, DCM) -> Aldehydes/carboxylic acids/esters (or ketones) (Corey-Schmidt oxidation)
  14. Dithianes + (1. n-BuLi, THF 2. E+ 3. HgO, H2O) -> Carbonyl derivatives via acyl anions (Corey-Seebach aka Seebach umpolung/reaction)
  15. 10 (or 20) alcohols + (PCC, DCM) -> Aldehydes (or ketones) (Corey-Suggs oxidation)
  16. 1,2-diols + (1. Thiophosgene or Thiocarbonyldiimidazole 2. (MeO)3P, Δ) -> Alkenes via 1,2-thionocarbonate (Corey-Winter aka Corey-Winter-Eastwood olefination/olefin synthesis)

CBS = Corey-Bakshi-Shibata, Ligand: THF (Tetrahydrofuran), Me2S, or PhNEt2, LAH = Lithium aluminum hydride (LiAlH4), SMEAH = Sodium bis(2-methyoxyethoxy)aluminum hydride (RedAl), Me2S=CH2 = A sulfur ylide, DMSO = Dimethyl sulfoxide (Me2S=O), R3R4C─S+R’R’’X─= A sulfur ylide, X = Halogen, Base = t-BuOK or NaH, TPP = Triphenylphosphine (Ph3P), rt = Room temperature, NCS = N-Chlorosuccinimide, R3R4CH─P(=O)(NR2)2 = An alkyl phosphondiamide, HBCat = Catecholborane, DCM = Dichloromethane (CH2Cl2), R3Si─C─HR3 = An α-silyl carbanion, R2CuLi = Lithium dialkyl cuprate, PDC = Pyridinium dichromate, E+ = Electrophile, PCC = Pyridinium chlorochromate, (MeO)3P = A trialkylphosphite

What other wheel(s) 🛞 of organic reactions would you like to see ❓Let Chemaficionado know in the comments below or at mychemistryhomework@gmail.com❗

References:

(1)    Wikipedia Contributors. Lhasa. Wikipedia. https://en.wikipedia.org/wiki/Lhasa.

(2)    Brown, C.; Ford, M. Higher Level Chemistry, 2nd ed.; Pearson Education: Harlow, Essex, 2014.

(3)    Ncert. Chemistry : Textbook for Class XI - Part.II; National Council Of Educational Research And Training: New Delhi.

(4)    Graham, T. W.; Fryhle, C. B.; Snyder, S. A. Organic Chemistry.; Hoboken, Nj John Wiley Et Sons, Inc, 2016.

(5)    Wikipedia Contributors. Elias James Corey. Wikipedia. https://en.wikipedia.org/wiki/Elias_James_Corey.

(6)    Wikipedia Contributors. Synthon. Wikipedia. https://en.wikipedia.org/wiki/synthon.

(7)    CBS catalyst. Wikipedia. https://en.wikipedia.org/wiki/CBS_catalyst.

(8)    https://en.wikipedia.org/wiki/Johnson%E2%80%93Corey%E2%80%93Chaykovsky_reaction

(9)    https://en.wikipedia.org/wiki/Corey%E2%80%93Fuchs_reaction

(10)    Wikipedia Contributors. Corey–House synthesis. Wikipedia.

(11)    Wikipedia Contributors. Corey–Itsuno reduction. Wikipedia.

(12)    https://en.wikipedia.org/wiki/Corey%E2%80%93Kim_oxidation

(13)    https://en.wikipedia.org/wiki/Corey%E2%80%93Link_reaction

(14)    Wikipedia Contributors. Corey–Nicolaou macrolactonization. Wikipedia.

(15)    Wikipedia Contributors. Peterson olefination. Wikipedia. https://en.wikipedia.org/wiki/peterson_olefination#variations.

(16)    https://en.wikipedia.org/wiki/Corey%E2%80%93Seebach_reaction

(17)    Pyridinium chlorochromate. Wikipedia. https://en.wikipedia.org/wiki/Pyridinium_chlorochromate.

(18)    https://en.wikipedia.org/wiki/Corey%E2%80%93Winter_olefin_synthesis

Comments

Post a Comment

Popular posts from this blog

How to Predict where an Electrophilic Aromatic Substitution May Occur in a Ring – Part 3

Image
An organic reaction in which an atom attached to an aromatic system (usually hydrogen) is substituted by an electrophile is referred to as  electrophilic aromatic substitution  ( S E Ar  or  EAS ). One of the most important  EASs  is halogenation. If Bromine water is added to Aniline, a multi-substituted product ( 2,4,6 -derivative) is obtained as Aniline is a strongly activating group (the same happens to Phenol). To generate the mono-substituted product, a protection, say, an acyl group is required. Question: Predict the major product(s) of the following reaction: Click/tap to enlarge the image Solution infographic: Click/tap to enlarge the image Motivated by EAS ❓ Let Chemaficionado know  in the comments below or at mychemistryhomework@gmail.com ❗ References: (1)      Wikipedia Contributors.  Electrophilic aromatic substitution . Wikipedia. https://en.wikipedia.org/wiki/Electrophilic_aromatic_substitution. (2)    ...
Read more

How to Carry out a Multistep Synthesis – Part 4

Image
Multistep synthesis  is the artificial execution of multiple organic chemical reactions to obtain one or more products by physical and chemical manipulations. Retrosynthetic analysis is a problem-solving approach in the organic syntheses, achieved by transforming a target molecule into simpler precursor structures regardless of any potential reactivity/interaction with reagents, and repeated until a simple or commercially available structure is reached, which can be used as a starting material to synthesize the target molecule. Question: How would you do the following transformation? Click/tap here to enlarge the image Solution infographic: Click/tap here to enlarge the image Let's keep in mind that any multistep synthesis is possible via several routes ❗Questions ❓ Let Chemaficionado know in the comments below or at mychemistryhomework@gmail.com ❗ References: (1)      Wikipedia Contributors.  Chemical synthesis . Wikipedia. https://en.wikipedia.org/wiki/Chemi...
Read more

How to Predict where an Electrophilic Aromatic Substitution May Occur in a Ring – Part 8

Image
An organic reaction in which an atom attached to an aromatic system (usually hydrogen) is substituted by an electrophile is referred to as  electrophilic aromatic substitution  ( S E Ar  or  EAS ). One of the most important  EASs  is nitration . Let's keep in mind that the presence of an activating group on the ring may complicate nitration. Question: Predict the major product(s) of the following reactions: Click/tap to enlarge the image Solution infographic: Click/tap to enlarge the image Eerie EAS chemistry❓ Let Chemaficionado know in the comments below or at mychemistryhomework@gmail.com ❗ References: (1)      Wikipedia Contributors.  Electrophilic aromatic substitution . Wikipedia. https://en.wikipedia.org/wiki/Electrophilic_aromatic_substitution. (2)      Brown, C.; Ford, M.  Higher Level Chemistry , 2nd ed.; Pearson Education: Harlow, Essex, 2014. ‌(3)     Electrophilic aromatic directing gro...
Read more