Korean, Edit

Chapter 16. Carboxylic Acids and Others

Recommended Post: 【Organic Chemistry】 Organic Chemistry Table of Contents

1. Overview

2. Carboxylic Acids

3. Acyl Chlorides

4. Acid Anhydrides

5. Esters

6. Amides

7. Nitriles

1. Overview

⑴ Common Reaction Principles

① Nucleophilic Attack, Electrophilic Attack

② Proton Transfer: Occurs intermolecularly between molecules rather than intramolecularly within a molecule

③ Tautomerization: Enol ↔ Ketone

④ Work-up: Precise identification of the base is not necessary

⑵ Properties

① Physical Properties

○ Carboxylic acids stabilize in dimeric forms due to hydrogen bonding

○ The dimeric structure results in carboxylic acids producing infrared absorption spectra around 2500-3000 cm^-1

② Comparison of Carbonyl Compound Reactivities

○ acyl halide ＞ acid anhydride ＞ aldehyde ＞ ketone ＞ ester ~ carboxylic acid＞ amide ＞ carboxylate ion

⑶ Carbonyl Compound Reaction Types

① Type 1: When the nucleophilicity of Y^- is greater than that of X^-

○ Type 1 is frequently observed in acyl chlorides

○ Carboxylic acids and others also exhibit a similar prevalence of Type 1

○ Aldehydes and ketones rarely undergo reactions of Type 1

Figure 1. Carbonyl Compound Reaction Type 1

② Type 2: When the nucleophilicity of Y^- is smaller than that of X^-

○ Most aldehydes and ketones follow Type 2

○ Even other reactions often seem to be merely an application of Type 2.

Figure 2. Carbonyl Compound Reaction Type 2

③ Type 3: Enone and 1,2-Addition Reaction: Occurs when the nucleophile is a strong nucleophile (e.g., Grignard reagent)

Figure 3. Carbonyl Compound Reaction Type 3

④ Type 4: Enone and 1,4-Addition Reaction (Michael addition): Occurs when the nucleophile is a weak nucleophile (e.g., MeSH)

Figure 4. Carbonyl Compound Reaction Type 4

2. Carboxylic Acids

⑴ Nomenclature

① Replace the -e of the alkane with -oic acid for naming

② Systemic nomenclature: Carbon number 1 becomes the carbon of -COOH

③ Common nomenclature: Adjacent carbon to -COOH becomes the α carbon

④ If there are alkenes, alkynes, etc., in the main chain, alkanoic acid becomes alkenoic acid, alkynoic acid, etc.

Figure 5. propenoic acid and propynoic acid

⑤ Comparison of Systemic Nomenclature (left) and Common Nomenclature (right)

○ Methanoic acid / Formic acid

○ Ethanoic acid / Acetic acid

○ Propanoic acid / Propionic acid

○ Butanoic acid / Butyric acid

○ Pentanoic acid / Valeric acid

○ Hexanoic acid / Caproic acid

○ Propenoic acid / Acrylic acid

○ 2-methoxybutanoic acid / α-methoxybutyric acid

○ 3-bromopentanoic acid / β-bromovaleric acid

○ 4-chlorohexanoic acid / γ-chlorocaproic acid

⑵ Reaction 1: Nucleophilic Addition Reaction

① Reaction 1-1: Formation of Acyl Chlorides: Formation of acyl chlorides through treatment with SOCl₂

Figure 6. Mechanism of Acyl Chloride Formation

Figure 7. Reaction for Generating phtaloyl chloride from phthalic acid

② Reaction 1-2: Fischer Esterification

○ (Formula) RCOOH + HOR’ react under acidic conditions to form RCOOR’ + H₂O

○ Carboxylic acids do not undergo acetal formation reactions, so they do not compete with Fischer esterification.

○ The reason that proton attaches to =O rather than -OH under acidic catalysis

○ Assumption: ROH must form a tetrahedral intermediate with carboxylic acid to facilitate the departure of the leaving group

○ Proton attaching to -OH: ROH results in =O becoming -O^- and -OH becoming -OH₂⁺, making the molecule unstable

○ Proton attaching to =O: ROH results in =OH⁺ becoming -OH, and the original -OH remains unchanged, stabilizing the intermediate

Figure 8. Fischer Esterification Mechanism

○ Under basic catalysis, only the acid-base reaction occurs, converting -COOH to -COO^-

③ Reaction 1-3: Amide Formation through Amine Addition

○ Reaction Conditions: Δ, EDC, DIC, or DCC

○ EDC: 1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide)

○ DIC: Diisopropylcarbodiimide

○ DCC: N,N‘-Dicyclohexylcarbodiimide

Figure 9. Mechanism of Amide Formation through Amine Addition

○ Point 1: EDC / NHS Chemistry

Figure 10. EDC/NHS Coupling

○ 1^st. EDC reacts with the carboxyl group of the target molecule

○ 2^nd. NHS stabilizes the EDC intermediate: Because the EDC intermediate can react with water

○ In other words, NHS prevents extensive reaction with water, promoting rapid amine reaction

○ 3^rd. Amines are attached to form amide bonds

○ Additional Notes

○ Generally, protocols indicate that EDC and NHS are added simultaneously to the target molecule solution.

○ Adding NHS first does not cause it to react with the target molecule

○ NHS (N-hydroxysuccinimide) Supplementation

○ NHS is the most frequently used activated ester

○ NHS-amine labeling is usually done in water as a solvent

○ Since NHS decreases water solubility, DMSO or DMF is sometimes added.

○ For reactions where water solubility is crucial, sulfo NHS is used

○ Point 2: Difference between EDC and DCC: EDC and DCC perform similar roles overall

○ EDC: Generates a water-soluble byproduct (urea byproduct) within 1 day

○ DCC: Performs the role of EDC in organic solvents, forming DCU

○ Point 3: Various Application Cases

Figure 11. Various Application Cases of Amide Formation through Amine Addition

④ Reaction 1-4: Carboxylic Acid Reduction

○ NaBH₄: No reaction occurs

○ LiAlH₄: Reduces carboxylic acids to alcohols through an aldehyde intermediate.

Figure 12. Carboxylic Acid Reduction by LiAlH₄

○ BH₃/THF: Reaction occurs

Figure 13. Carboxylic Acid Reduction by BH₃/THF

⑤ Reaction 1-5: Organic Lithium Reaction: Forms ketones

Figure 14. Mechanism of Organic Lithium Reaction

⑥ Reaction 1-6: Exchange Reaction of -OH in Carboxylic Acid: Confirmed by isotopic effect

⑶ Other Reactions

① Hell-Vollhard-Zelinsky Reaction (HVZ Reaction)

○ Reaction of carboxylic acids at the α position with bromine or chlorine in the presence of phosphorus

○ Application 1. RCOCl + NCS, HCl, SOCl₂, 70 ℃

○ Application 2. RCOCl + NBS, HBr, SOCl₂, 70 ℃

○ Application 3. RCOCl + I₂, HI, SOCl₂, 85 ℃

② Hundsdiecker Reaction: RCOOAg + Br₂, CCl₄ → R-Br

③ Kochi Reaction: A variation of the Hundsdiecker Reaction. RCOOH + Pb(OAC)₄, + LiCl - CO₂ → R-Cl + LiPb(OAc)₃ + HOAc

④ After converting the carboxylic acid to its dianion form, an alkylation reaction occurs at the alpha position. 1. NaH, 55 ℃, THF, 2. LDA, 10-35 ℃

⑷ Major Mistakes Related to Carboxylic Acid Reactions

① Alkoxide and Carboxylic Acid

Figure 15. Alkoxide and Carboxylic Acid

② Grignard Reagent and Carboxylic Acid

Figure 16. Grignard Reagent and Carboxylic Acid

⑸ Synthesis Methods

① Oxidation of Alkenes: 1. KMnO₄, OH^-, heat, 2. H₃O⁺ / 1. O₃, 2. H₂O₂

② Oxidation of Alkyl Benzenes: 1. KMnO₄, OH^-, heat, 2. H₃O⁺ leads R-Me to become R-COOH

③ Oxidation of the Benzene Ring Itself: 1. O₃, CH₃CO₂H, 2. H₂O₂ leads R-Ph to become R-COOH

④ Oxidation of Primary Alcohols: 1. KMnO₄, OH^-, heat, 2. H₃O⁺ / H₂CrO₄

⑤ Oxidation of Aldehydes: Ag(NH₃)₂⁺OH^- (Silver Mirror Reaction) or H₂CrO₄

⑥ Oxidative Cleavage of Ketones: 1. KMnO₄, H₂O, NaOH, 2. H₃O⁺

⑦ Haloform Reaction: 1. X₂ / NaOH, 2. H₃O⁺

⑧ Hydrolysis of Cyanide (RCN)

Figure 17. Cyanide Hydrolysis

⑨ Decarboxylation Reaction of Malonic Acid or Malonic Acid Esters

⑩ Carbonation Reaction of Grignard Reagent

○ Grignard reagents are used in ether solvents

○ CO₂ is supplied in the form of dry ice

Figure 18. Carbonation Reaction Types of Grignard Reagent Type 1

3. Acyl Chlorides

⑴ Nomenclature

① If the parent chain is cyclic, add carbonyl halide as a suffix to cycloalkane and name it.

② For substituents in a chain, name them in alphabetical order followed by -oxo.

③ For substituents in a cyclic compound, add halocarbonyl as a prefix and name it.

④ Comparison between systematic naming (left) and common naming (right)

○ ethanoyl chloride / acetyl chloride

○ 3-methylpentanoyl chloride / β-methylvaleryl chloride

⑵ Characteristics

① Acyl chlorides are highly reactive and can react with moisture in the air.

② Acidity: H₃O⁺ ＜ HCl, Basicity: H₂O ＞ Cl^-

⑶ Reaction 1. Nucleophilic addition reaction

① Reaction 1-1. Reaction with carboxylates: Forms anhydrides. CH₃CO₂^-

② Reaction 1-2. Reaction with alcohols to form esters

③ Reaction 1-3. Reaction with amines to form amides

○ Since the above reaction is not a step-by-step process, adding a small amount of amine will result in some amine performing the work-up, leading to the presence of three different states.

○ Generally, excess of 2 equivalents of amine is used: Only products are formed.

Figure 19. Mechanism of amide formation reaction

④ Reaction 1-4. Formation of carboxylic acids through hydrolysis: H₃O⁺

⑤ Reaction 1-5. Alpha halogenation reaction: HX, SOCl₂

⑷ Reaction 2. Reduction reaction

① Reaction 2-1. Reaction with NaBH₄, LAH to generate primary alcohols: 1. LiAlH₄, 2. H₃O⁺

② Reaction 2-2. Reaction with LiAlH(O-t-Bu₃)₃ to generate aldehydes: 1. LiAlH(OC(CH₃)₃)₃, 2. H₂O

③ Reaction 2-3. Rosenmund reduction: H₂ / Pd, Quinoline, BaSO₄

⑸ Reaction 3. Reaction with organometallic reagents

① Reaction 3-1. Reaction with Grignard reagents to generate tertiary alcohols: 1. 2 RMgX, 2. H₃O⁺

② Reaction 3-2. Reaction with Gilman reagents to generate ketones: (Ph)₂CuLi, ether

⑹ Reaction 4. Ketone formation via Benzene and Friedel-Crafts acylation

⑺ Reaction 5. Rearrangement reactions

① Reaction 5-1. Curtius rearrangement

○ Reaction where isocyanate and nitrogen gas are formed from acyl azides

○ Although related to azide portion, the problems usually start with acyl chlorides

○ Importance: Widely used for amine synthesis

Figure 20. Curtius rearrangement mechanism (applications)

② Reaction 5-2. Wolff rearrangement

○ Ag₂O + H₂O forms OH^-. Δ or hν promotes H detachment

○ Wolff rearrangement occurs with aldehydes and ketones

○ Wolff rearrangement doesn’t happen with carboxylic acids

○ (Formula) Acyl chloride + diazomethane → diazo ketone → ketene

○ Although related to azide portion, the problems usually start with acyl chlorides

Figure 21. Wolff rearrangement mechanism

③ Reaction 5-3. Formation of ketene upon treatment with tertiary amines

⑻ Synthesis Methods

① Carboxylic acid + SOCl₂

Figure 22. Acyl chloride synthesis using carboxylic acid and SOCl₂

② PCl₃

③ PCl₅

4. Acid Anhydrides

⑴ Nomenclature

① Remove “acid” from carboxylic acid and add “anhydride” to name anhydrides.

② For cyclic compounds, add “carboxylic anhydride” as a suffix to cycloalkane.

③ For substituents in chains, use alkanoyloxy- or common name + oxy as a prefix.

④ For substituents in cyclic compounds, use alkanoylcarbonyl or common name + carbonyl as a prefix.

⑤ For cyclic anhydrides, add “alkanedioic anhydride” as a suffix to alkane: Common names are often used.

⑥ Comparison between systematic naming (left) and common naming (right)

○ ethanoic anhydride / acetic anhydride, symmetrical anhydride

○ ethanoic methanoic anhydride / acetic formic anhydride, mixed anhydride

⑵ Reactions

① Reaction 1. Nucleophilic addition reaction

○ 1-1. Formation of carboxylic acid: Hydrolysis reaction

Figure 23. Formation of carboxylic acid through hydrolysis of anhydride

○ 1-2. Ester formation reaction: Anhydride + alcohol or carboxylic acid

Figure 24. Esterification reaction of anhydride

○ 1-3. Amide formation reaction: Anhydride + ammonia/imine + NaOH

Figure 25. Amide formation reaction

○ 1-4. Formation of imides from cyclic anhydrides and ammonia: NH₃, H₂O, H₃O⁺

○ 1-5. Reaction with alcohols to form esters: pyridine / (CF₃CO)₂O, R’OH

② Reaction 2. Nucleophilic aromatic substitution reaction (S_NAr)

○ 2-1. Reaction with aromatic compounds and nitration: Occurs under HNO₃

Figure 26. Furan and nitration

○ 2-2. Reaction with aromatic compounds and Friedel-Crafts acylation to form ketones: Occurs under BF₃

Figure 27. Furan undergoing Friedel-Crafts acylation

○ 2-3. Synthesis of fluorescein: phthalic anhydride + 2 × resorcinol → fluorescein (catalyst: ZnCl₂)

Figure 28. Fluorescein synthesis

③ Reaction 3. Oxidation reactions

○ Reaction with Grignard, organolithium reagents to form secondary, tertiary alcohols: 1. 2RMgX, 2. H₃O⁺

○ Reaction with NaBH₄, LAH to generate methyl, primary alcohols: 1. LiAlH₄, 2. H₃O⁺

○ Imine dehydration reaction: Reaction of HRC=N-OH with anhydride produces R-C≡N

④ Cases where no reaction occurs

○ Anhydride is not converted to acyl chloride when treated with NaCl.

○ Doesn’t react with SOCl₂

○ Doesn’t react with Gilman reagents

⑶ Synthesis Methods

① Carboxylic acid + heat / P₂O₅

Figure 29. Acid anhydride synthesis

5. Esters

⑴ Nomenclature

① Systematic naming: List substituents on O first, then remove -ic acid from carboxylic acid naming and add -ate.

② For cyclic compounds, add carboxylate to cycloalkane.

③ For substituents in chains, name them as number - alkoxy - number - oxo.

④ For substituents in cyclic compounds, use alkoxy carbonyl as a prefix.

⑤ Comparison between systematic naming (left) and common naming (right)

○ ethyl ethanoate / ethyl acetate

○ phenyl propanoate / phenyl propionate

○ methyl 3-bromobutanoate / methyl β-bromobutyrate

⑥ Systematic naming of carboxylic acid conjugate bases (left) and common naming (right)

○ sodium methanoate / sodium formate

○ potassium ethanoate / potassium acetate

⑵ Reaction 1. Nucleophilic addition reaction

① Reaction 1-1. Acid-catalyzed hydrolysis reaction: Because the reverse reaction is also possible, a specific equilibrium state is reached.

Figure 30. Ester hydrolysis reaction mechanism

② Reaction 1-2. Saponification reaction: Base-catalyzed hydrolysis reaction

○ Reaction conditions example: 1. NaOH, H₂O, 2. HCl, H₂O

○ The reaction does not proceed in the reverse direction due to the concentration of leaving group (i.e. OH^-) determined by pH.

Figure 31. Saponification reaction mechanism

③ Reaction 1-3. Trans-esterification reaction: Can occur under both acidic and basic conditions

Figure 32. Trans-esterification reaction

④ Reaction 1-4. Reaction leading to amide formation with amines

Figure 33. Reaction leading to amide formation with amines

⑤ Reaction 1-5. Polymerization reaction using cyclic esters as monomers: Ring-opening reaction occurs iteratively

⑶ Reaction 2. Reduction reaction

① Reaction 2-1. Alcohol formation reaction with LAH (LiAlH₄)

Figure 34. Alcohol formation reaction with LAH

② Reaction 2-2. NaBH₄ reduction reaction

○ Less electrophilic than aldehydes and ketones, so esters are not completely reduced by NaBH₄.

○ At low temperatures, esters can only be reduced to aldehydes.

○ NaBH₄ can only reduce esters under AlCl₃, generally not capable of reducing carboxylic acids.

Figure 35. NaBH₄ reduction reaction equation

③ Reaction 2-3. Reduction reaction with DIBAL-H ([(CH₃)₂CHCH₂]₂AlH)

Figure 36. Reduction reaction with DIBAL-H

⑷ Reaction 3. Acid-base reactions

① Overview

○ Esters are less acidic than aldehydes and ketones

○ Reason: The conjugate base of an ester competes with the resonance lone pair of the ester, preventing resonance stabilization

② Reaction 3-1. Alpha halogenation of esters: 1. LDA, THF, 2. Br₂

⑸ Reaction 4. Oxidation reactions

① Reaction 4-1. Reaction with organometallic reagents

○ Use sufficient organic reagent to ensure complete reaction since esters, ketones, and alcohols coexist

○ Requires 2 equivalents of organic reagent for complete reaction, slightly exceeding that in practice

Figure 37. Tertiary alcohol formation reaction with Grignard reagent addition

⑹ Reaction 5. Decarboxylation reaction: Requires high temperatures

Figure 38. Ester decarboxylation reaction

⑺ Reaction 6. Claisen rearrangement reaction of orthoesters

Figure 39. Claisen rearrangement reaction of orthoester

⑻ Synthesis Methods

① Ester synthesis using diazomethane: H₂C-N≡N

② Synthesis through alkylation reaction by S_N2 of carboxylate

③ Baeyer-Villiger oxidation

④ Fischer esterification: Acid-catalyzed esterification reaction

⑤ Carboxylic acid + intramolecular esterification → lactone (cyclic ester)

⑥ Polyester synthesis

6. Amides

⑴ Nomenclature

① Mention substituents attached to the amide nitrogen first

○ N-cyclohexylpropanamide

○ N-ethyl-_N_-methylpentanamide

○ N,N-diethylbutanamide

② Carbon of C=O becomes carbon 1, similar to a carbonyl group

③ If alkyl-substituted at nitrogen, prefix N- to the substituent name

④ In cyclic cases, add carboxamide after cycloalkane

⑤ In chain cases treated as substituents, name as number - alkylamino - number - oxo

⑥ In cyclic cases treated as substituents, name as alkylcarbamoyl

⑦ Comparison of systematic naming (left) and common naming (right)

○ ethamide / acetamide

○ 4-chlorobutanamide / γ-chlorobutyramide

⑵ Properties

① Primary and secondary amides can form dimers through intermolecular hydrogen bonding

② Boiling point of amides is higher than carboxylic acids

⑶ Reaction 1. Amide hydrolysis reaction

① Reaction 1-1. Acid-catalyzed amide hydrolysis reaction

Figure 40. Acid-catalyzed amide hydrolysis reaction

② Reaction 1-2. Base-catalyzed amide hydrolysis reaction

Figure 41. Base-catalyzed amide hydrolysis reaction

③ Reaction 1-3. Reaction with LiAlH4 to form amine: Requires 2 equivalents of LiAlH₄

Figure 42. Reaction mechanism of amine formation from amide using LiAlH₄

⑷ Reaction 2. Other reactions

① Reaction 2-1. Oxidation reaction: Does not react with Grignard reagents

② Reaction 2-2. Polymerization reaction via ring opening of cyclic amides as monomers

③ Reaction 2-3. Hofmann rearrangement reaction

○ Reactant is halogen gas, and intermediates include haloamide, isocyanate, carbamic acid.

Figure 43. Hofmann rearrangement reaction

④ Reaction 2-4. Bischler-Napieralski reaction: Ring formation reaction

Figure 44. Bischler-Napieralski reaction

⑤ Reaction 2-5. Luminol reaction

Figure 45. Luminol reaction

○ Component 1. Luminol reagent: White or yellow solid. Hydrophobic. Produces blue light when mixed with oxidizer

○ Component 2. Base: Sodium hydroxide

○ Component 3. Hydrogen peroxide: Oxidizer supplying oxygen. 2H₂O₂ → O₂ + 2H₂O

○ Component 4. Catalyst: Iron ion in hemoglobin, K₃[Fe(CN)₆], KIO₄, etc.

○ Use 1. Detecting bloodstains at crime scenes

○ Use 2. Detecting copper, iron, cyanide in laboratories

⑸ Synthesis Methods

① From carboxylic acids: Carried out under conditions with EDC / NHS, DCC, or DIC catalysts

Figure 46. EDC/NHS coupling

② From acyl chlorides: Requires 2 equivalents of amine ( ∵ amine reacts with leaving group)

③ From acid anhydrides

④ Ritter reaction: Conversion of nitrile to amide

⑤ From amines

⑥ Beckmann rearrangement

7. Nitriles

⑴ Nomenclature

① When nitrile has the highest priority, carbon of -CN is labeled as carbon 1

② If nitrile is part of a ring, name as cycloalkanecarbonitrile

③ If nitrile is a substituent in chain or ring, use cyano- prefix for naming

④ Comparison of systematic naming (left) and common naming (right)

○ ethanenitrile / acetonitrile, methyl cyanide

○ 5-methylhexanenitrile / δ-methylcapronitrile, isohexyl cyanide

○ propenenitrile / acrylonitrile

⑵ Reaction 1. Nucleophilic addition reaction

① Reaction 1-1. Acid-catalyzed hydrolysis: Forms carboxylic acid

Figure 47. Acid-catalyzed hydrolysis mechanism

② Reaction 1-2. Base-catalyzed hydrolysis

③ Reaction 1-3. Ritter reaction

○ Conversion of nitrile to amide

○ Ph-C≡N + ROH + H₂SO₄, H₂O → Ph-CO-NH-R

⑶ Reaction 2. Hydrogenation reaction

① Reaction 2-1. Amine formation via LAH (LiAlH₄)

Figure 48. Amine formation via LAH (LiAlH4)

② Reaction 2-2. Aldehyde formation via DIBAL-H

Figure 49. Aldehyde formation via DIBAL-H

③ Reaction 2-3. Hydrogenation with Raney nickel catalyst: Raney nickel serves the role of gently moderating reactions to prevent the escape of nitrogen.

Figure 50. Hydrogenation with Raney nickel catalyst

⑷ Reaction 3. Organometallic reagent reactions

① Reaction 3-1. Ketone formation by addition of Grignard reagent

Figure 51. Ketone formation by adding Grignard reagent

② Reaction 3-2. Ketone formation by adding organic lithium reagents

③ Gilman Reagent (R₂CuLi) does not react with carbonyl group (C=O) and nitrile

⑸ Reaction 4. Azide-alkyne cycloaddition

① Also known as click chemistry, discussed by K. Barry Sharpless starting in 1998

② Reaction 4-1. 1,3-dipolar azide-alkyne cycloaddition

○ Above 100 ℃. Hours-days. Heat-catalyzed conjugetion reaction

○ Rapid reaction when R₂, R₃ are electron-withdrawing groups

Figure 52. 1,3-dipolar cycloaddition

○ Application 1. azide + cyclooctyne

Figure 53. Cycloaddition with azide and cyclooctyne

○ Application 2. tetrazine + trans-cyclooctene

Figure 54. Cycloaddition with tetrazine and trans-cyclooctene

③ Reaction 4-2. CuAAC (Copper-catalyzed azide-alkyne cycloaddition)

Figure 55. CuAAC reaction

④ Reaction 4-3. RuAAC (Ruthenium-catalyzed azide-alkyne cycloaddition)

Figure 56. RuAAC reaction

⑤ Reaction 4-4. SPAAC (Copper-free stain-promoted azide-alkyne cycloaddition)

○ A recently introduced technique

○ Addition reaction method applicable to soft molecules like biomolecules

⑹ Synthesis Methods

① Reaction of NaCN with R-X via S_N2

② CuCN treatment of Ar-N₂ in Sandmeyer reaction

③ Reaction of aldehydes and ketones with NaCN reaction: CN^- attacks carbonyl carbon

④ Dehydration reaction of amides: Conversion to nitrile using dehydration reagents like P₄O₁₀, (CH₃CO)₂O, SOCl₂, POCl₃

Input: 2019.02.28 23:13

Modified: 2022.02.02 19:28