Organic Reactions Cheatsheet

Cheatsheet Content

1. Catalytic Reduction (Hydrogenation) $C=C + H_2 \xrightarrow{Pd, Pt, Ni} C-C$ Raney Ni: Finely divided Ni. Hydrogenation of alkenes is a syn addition . Example: $CH_3-CH=CH_2 \xrightarrow{H_2/Pt} CH_3-CH_2-CH_3$ Deuterium Addition ($D_2$): cis -2-butene + $D_2$ (syn addition) $\rightarrow$ Meso compound (optically inactive) trans -2-butene + $D_2$ (syn addition) $\rightarrow$ Racemic mixture 2. Reduction of Alkene using Di-imide $C=C + N_2H_2 \rightarrow C-C$ (syn addition) Di-imide ($N_2H_2$) is generated from $N_2H_4 + H_2O_2 \rightarrow N_2H_2 + 2H_2O$. 3. Reduction of Alkynes using Lindlar's Catalyst $R-C \equiv C-R' \xrightarrow{H_2 / Pd-BaSO_4} R-CH=CH-R'$ Lindlar's catalyst (Pd-BaSO$_4$ / Quinoline) is a poisoned catalyst. Forms cis alkene . Example: $CH_3-C \equiv C-CH_3 \xrightarrow{H_2/Pd-BaSO_4} CH_3-CH=CH-CH_3$ ( cis ) 4. Reduction of Alkynes using Birch Reduction $R-C \equiv C-R' \xrightarrow{Na/Liq. NH_3} R-CH=CH-R'$ Forms trans alkene . $Na/Liq. NH_3$ is a paramagnetic blue solution due to ammoniated electrons. Example: $CH_3-C \equiv C-CH_3 \xrightarrow{Na/Liq. NH_3} CH_3-CH=CH-CH_3$ ( trans ) 5. Clemmensen's Reduction (Acidic Medium) $R-CO-R' \xrightarrow{Zn(Hg)/Conc. HCl} R-CH_2-R' + ZnCl_2 + H_2O$ Zn(Hg) is zinc amalgam, a source of nascent hydrogen. Used for reducing ketones/aldehydes to alkanes. 6. Wolf-Kishner Reduction (Basic Medium) $R-CO-R' \xrightarrow{(i) N_2H_4/H^+, (ii) NaOH/\Delta} R-CH_2-R' + N_2 \uparrow$ Generally better for reducing aldehydes. 7. Decarboxylation (Removal of $CO_2$) $R-COO^-Na^+ + NaOH + CaO \xrightarrow{\Delta} R-H + Na_2CO_3$ Soda lime (NaOH + CaO). Carboxylic acids with electron-withdrawing groups at the $\alpha$-carbon decarboxylate rapidly. Example: $\beta$-keto acid $\xrightarrow{\Delta} ketone + CO_2$ 8. Wurtz Reaction $R-X + 2Na + X-R' \xrightarrow{ether} R-R' + 2NaX$ Characteristics: Methane cannot be prepared. Better yield with symmetrical alkanes (even number of carbons). If two different alkyl halides are used, at least three products are formed ($R-R$, $R'-R'$, $R-R'$). Cannot use alkyl halides with acidic hydrogens. 9. Corey-House Synthesis $R-X + R'_2CuLi \xrightarrow{ether} R-R' + R'-Cu + LiX$ Used to form unsymmetrical alkanes. $R-X$ should preferably be $CH_3-X$ or alkyl halide to avoid elimination. 10. Halogenation of Alkanes $CH_4 + Cl_2 \xrightarrow{h\nu} CH_3-Cl + HCl$ (and further halogenation to $CH_2Cl_2, CHCl_3, CCl_4$) 11. Nitration Lower alkanes do not undergo nitration at ordinary temperatures. Long chain alkanes undergo nitration at high temperatures ($450^\circ C$). C-H and C-C bonds cleave. Example: $CH_3-CH_2-CH_3 + HNO_3 \xrightarrow{450^\circ C} CH_3-CH_2-CH_2-NO_2 + CH_3-CH(NO_2)-CH_3 + ...$ 12. Sulphonation Lower alkanes do not undergo sulphonation. n-Hexane is the smallest alkane that can undergo sulphonation. Example: $C_6H_{14} + H_2S_2O_7 \xrightarrow{40^\circ C} C_6H_{13}SO_3H + H_2O$ (oleum) 13. Dehydration of Alcohols $R-CH_2-CH_2-OH \xrightarrow{Conc. H_2SO_4/\Delta \text{ or } Conc. H_3PO_4/\Delta \text{ or } Al_2O_3/\Delta} R-CH=CH_2$ Forms alkene. Saytzeff's Rule: More substituted alkene will be the major product (more stable). Remove H from the $\beta$-carbon with the least number of hydrogens. Goes via E1 mechanism. Carbocation rearrangement can occur. 14. Dehydrohalogenation of Alkyl Halides $R-CH_2-CH(X)-CH_3 \xrightarrow{Alcoholic KOH/\Delta} R-CH=CH-CH_3$ Goes via E2 mechanism. Major product formed by Saytzeff's Rule (more stable alkene). 15. Dehalogenation of Vicinal Dihalides (Bromides) $Br-CH_2-CH_2-Br \xrightarrow{Zn/\Delta} CH_2=CH_2 + ZnBr_2$ Goes via E2 mechanism. 16. Wittig Reaction $C=O + Ph_3P=CH-R \rightarrow C=CH-R + Ph_3P=O$ Phosphorus ylide. 17. Acid Catalyzed Hydration of Alkenes (Formation of Alcohols) $C=C \xrightarrow{H_3O^+ \text{ or } H_2SO_4/H_2O} C(OH)-CH$ Addition of $H_2O$ takes place according to Markovnikov's Rule. Occurs via carbocation formation, so rearrangements are possible. 18. Oxymercuration-Demercuration (OMDM) $C=C \xrightarrow{(i) Hg(OAc)_2/THF, H_2O, (ii) NaBH_4/OH^-} C(OH)-CH$ Markovnikov addition of $H_2O$. No carbocation intermediate, so no rearrangement . OH comes from $H_2O$, H comes from $NaBH_4$. 19. Alkoxymercuration-Demercuration $C=C \xrightarrow{(i) Hg(OAc)_2/THF, ROH, (ii) NaBH_4/OH^-} C(OR)-CH$ Forms ethers. Markovnikov addition of H and OR. Mechanism similar to OMDM, no rearrangement. 20. Hydroboration-Oxidation (HBO) $C=C \xrightarrow{(i) B_2H_6/THF, (ii) H_2O_2/OH^-} C(OH)-CH$ Anti-Markovnikov addition of $H_2O$. No carbocation, so no rearrangement . 21. Hydroboration-Reduction (Alkanes are formed) $C=C \xrightarrow{(i) B_2H_6/THF, (ii) CH_3COOH} CH_2-CH_2$ 22. Hydroxylation of Alkenes with Baeyer's Reagent (Cold, Alkaline $KMnO_4$) $C=C \xrightarrow{Cold, Alk. KMnO_4} C(OH)-C(OH)$ (syn addition) Forms syn -diols. 23. Hydroxylation of Alkenes with $OsO_4$ $C=C \xrightarrow{(i) OsO_4/pyridine, (ii) NaHSO_3/H_2O} C(OH)-C(OH)$ (syn addition) 24. Reaction of Alkenes with Peracids (Epoxidation) $C=C \xrightarrow{m-CPBA} cyclic \text{ ether (epoxide)}$ m-CPBA: meta -Chloroperbenzoic acid. 25. Hydroxylation of Alkenes by Prevost Conditions $C=C \xrightarrow{(i) I_2/CH_3COOAg, CCl_4, (ii) H_2O} C(OH)-C(OH)$ (trans addition) 26. Woodward Condition $C=C \xrightarrow{(i) I_2/CH_3COOAg \text{ (wet)}, (ii) H_2O} C(OH)-C(OH)$ (syn addition) 27. Reaction of Alkenes with Hot Acidic $KMnO_4$ Similar to oxidative ozonolysis, cleaves the double bond. 28. Ozonolysis of Alkenes $C=C \xrightarrow{(i) O_3, (ii) Zn/H_2O \text{ or } (CH_3)_2S} C=O + C=O$ (Reductive ozonolysis) 29. Addition of HX on Alkenes $C=C + HX \rightarrow C(X)-CH$ Markovnikov addition. Rearrangements can occur. Reactivity order: $HI > HBr > HCl$. 30. Reaction of Alkenes with HBr/Peroxide (Kharasch Effect) $C=C + HBr \xrightarrow{Peroxide} C-CH_2-Br$ (Anti-Markovnikov addition) Peroxide effect is not applicable to HCl or HI due to endothermic propagation steps. Goes via free radical mechanism, no rearrangement. 31. Reaction of Alkenes with NBS (N-Bromosuccinimide) Used for allylic and benzylic bromination. Example: $CH_2=CH-CH_3 \xrightarrow{NBS} CH_2=CH-CH_2-Br$ Goes via formation of allylic/benzylic free radicals. 32. Halogenation of Alkenes $C=C + Br_2 \xrightarrow{CCl_4} C(Br)-C(Br)$ (Anti-addition) cis -alkene + $Br_2 \rightarrow$ Racemic mixture trans -alkene + $Br_2 \rightarrow$ Meso compound 33. Halohydrin Formation (Addition of $X_2/H_2O$) $C=C \xrightarrow{Br_2/H_2O \text{ or } Cl_2/H_2O} C(OH)-C(X)$ Addition of OH and X takes place according to Markovnikov's Rule. Anti-addition. Used as a test for unsaturation (decolorizes $Br_2$ water). 34. Allylic or Benzylic Chlorination $R-CH_3 \xrightarrow{SO_2Cl_2/\Delta \text{ or } Cl_2/\Delta} R-CH_2-Cl$ Free radical path. 35. Carbene Insertion Reaction $C=C + CH_2N_2 \xrightarrow{\Delta} cyclic \text{ alkane}$ Forms cyclopropane derivatives (Ettinger carbene). 36. Wacker's Process $CH_2=CH_2 \xrightarrow{PdCl_2/H_2O, O_2} CH_3-CHO$ 38. Dehalogenation of Vicinal Dihalides and Geminal Dihalides $Br-CH_2-CH(Br)-R \xrightarrow{NaNH_2 \text{ (alc.)}} CH_2=C(Br)-R \xrightarrow{NaNH_2 \text{ (excess)}} CH \equiv C-R$ 39. Dehalogenation of Tetrahalides $Br_2CH-CHBr_2 \rightarrow CH \equiv CH$ 40. Reaction of Haloform with Ag $2CHCl_3 + 6Ag \rightarrow CH \equiv CH + 6AgCl$ Chloroform is a sweet-smelling liquid. 41. Reactions of Acetylene $CH \equiv CH + HCl \rightarrow CH_2=CHCl$ (Vinyl chloride) $CH \equiv CH + H_2O \rightarrow CH_3CHO$ (Acetaldehyde) 42. Lewisite Formation $CH \equiv CH + AsCl_3 \rightarrow CH_2=CHAsCl_2$ (Lewisite - poisonous gas) 43. Addition of Water to Alkynes $R-C \equiv CH \xrightarrow{HgSO_4/H_2SO_4} R-CO-CH_3$ (Markovnikov - ketone) $R-C \equiv CH \xrightarrow{(i) B_2H_6/THF, (ii) H_2O_2/OH^-} R-CH_2-CHO$ (Anti-Markovnikov - aldehyde) 44. Ozonolysis of Alkynes Reductive: $R-C \equiv C-R' \xrightarrow{(i) O_3, (ii) Zn/H_2O} R-CO-CO-R'$ ($\alpha, \beta$-diketones) Oxidative: $R-C \equiv C-R' \xrightarrow{(i) O_3, (ii) H_2O_2/H_2O} R-COOH + R'-COOH$ 45. Polymerization of Acetylene $3CH \equiv CH \rightarrow \text{Benzene}$ (Red hot iron tube) $nCH \equiv CH \rightarrow \text{Polyacetylene}$ (Tubelike structure, non-aromatic) 46. Dimerization/Trimerization of Acetylene $2CH \equiv CH \xrightarrow{CuCl/NH_4Cl} CH_2=CH-C \equiv CH$ (Vinyl acetylene) $3CH \equiv CH \xrightarrow{CuCl/NH_4Cl} CH_2=CH-C \equiv C-CH=CH_2$ (Divinyl acetylene) 47. Reaction of Alkyne with Tollen's Reagent $R-C \equiv CH + 2[Ag(NH_3)_2]^+OH^- \rightarrow R-C \equiv C-Ag \downarrow + 2NH_3 + H_2O$ Given only by terminal alkynes, forms a white precipitate. 48. Decarboxylation of Benzoic Acid $C_6H_5-COOH \xrightarrow{NaOH+CaO/\Delta} C_6H_6 + Na_2CO_3 + H_2O$ 49. Reduction of Phenols (Zn/Dust) $C_6H_5-OH \xrightarrow{Zn/\Delta} C_6H_6 + ZnO$ 50. From Benzenesulphonic Acid $C_6H_5-SO_3H \xrightarrow{H_2O_2/H_2SO_4 \text{ or } NaOH/\Delta} C_6H_5-OH$ 51. From Benzene Diazonium Chloride $C_6H_5-N_2^+Cl^- \xrightarrow{H_2O/\Delta} C_6H_5-OH + N_2 + HCl$ 52. From Alcohols (Preparation of Alkyl Halides) $ROH + PCl_5 \rightarrow R-Cl + POCl_3 + HCl$ $3ROH + PCl_3 \rightarrow 3R-Cl + H_3PO_3$ $ROH + SOCl_2 \rightarrow R-Cl + SO_2 \uparrow + HCl \uparrow$ (Darzen's method, best method, products are gases) 53. Finkelstein Reaction $R-Cl/Br + NaI \xrightarrow{Acetone} R-I + NaCl/NaBr \downarrow$ Used for preparation of R-I. Goes via $S_N2$ path, inversion of configuration. 54. Swarts Reaction $R-Cl/Br + AgF/Hg_2F_2/SbF_3 \rightarrow R-F + AgCl/Br$ Used for preparation of R-F. 55. Borodine Hunsdiecker Reaction $R-COOAg + Br_2 \xrightarrow{CCl_4/\Delta} R-Br + AgBr \downarrow + CO_2 \uparrow$ Free radical mechanism. 56. $S_N2$ Reaction (Substitution Nucleophilic Bimolecular) $Nu^- + R-X \rightarrow Nu-R + X^-$ Second order, one step (concerted) mechanism. Inversion of configuration (Walden inversion). Rate: $Rate = k[R-X][Nu^-]$ Reactivity of R-X: $CH_3-X > 1^\circ > 2^\circ > 3^\circ$ (due to steric hindrance). Leaving group ability: $I^- > Br^- > Cl^- > F^-$. Solvent: Polar aprotic solvents (e.g., DMSO, acetone, DMF). 57. $S_N1$ Reaction (Substitution Nucleophilic Unimolecular) $R-X \rightarrow R^+ + X^- \xrightarrow{Nu^-} Nu-R$ First order, two step mechanism. Carbocation intermediate, so rearrangements are possible. Racemization (partial). Rate: $Rate = k[R-X]$ Reactivity of R-X: $3^\circ > 2^\circ > 1^\circ > CH_3-X$. Leaving group ability: $I^- > Br^- > Cl^- > F^-$. Solvent: Polar protic solvents (e.g., $H_2O$, alcohols). 58. $S_NAr$ Reactions (Substitution Nucleophilic Aromatic) Requires strong electron-withdrawing groups (e.g., $NO_2$) ortho or para to the leaving group. Phenols do not undergo $S_N2$ reaction under normal conditions due to partial double bond character of C-X bond. Reactivity of aryl halides: Ar-F > Ar-Cl > Ar-Br > Ar-I. Dow's Process: $C_6H_5-Cl \xrightarrow{NaOH, 350^\circ C} C_6H_5-ONa \xrightarrow{H^+} C_6H_5-OH$ 59. $S_N(Benzyne)$ Occurs when $S_NAr$ conditions are too harsh or EWG are absent. Involves a benzyne intermediate (triple bond). Example: $C_6H_5-X \xrightarrow{NaNH_2/Liq. NH_3} C_6H_5-NH_2$ 60. $S_NNGP$ (Substitution Nucleophilic Neighbouring Group Participation) Involves an intramolecular nucleophile. Leads to retention of configuration (two $S_N2$ steps). Neighboring groups can be lone pairs, negative charges, or $\pi$-bonds. Most common rings formed in the transition state are 3, 4, 5-membered. 61. From Benzene Diazonium Chloride (Sandmeyer, Gattermann, Balz-Schiemann) $C_6H_5-NH_2 \xrightarrow{NaNO_2/HCl, 0-5^\circ C} C_6H_5-N_2^+Cl^-$ $C_6H_5-N_2^+Cl^- \xrightarrow{CuCl/HCl} C_6H_5-Cl$ (Sandmeyer) $C_6H_5-N_2^+Cl^- \xrightarrow{CuBr/HBr} C_6H_5-Br$ (Sandmeyer) $C_6H_5-N_2^+Cl^- \xrightarrow{Cu/HCl} C_6H_5-Cl$ (Gattermann) $C_6H_5-N_2^+Cl^- \xrightarrow{HBF_4, \Delta} C_6H_5-F$ (Balz-Schiemann) $C_6H_5-N_2^+Cl^- \xrightarrow{KI} C_6H_5-I$ $C_6H_5-N_2^+Cl^- \xrightarrow{H_3PO_2/\Delta \text{ or } EtOH/\Delta} C_6H_6$ 62. Raschig's Process $C_6H_6 + HCl + 1/2 O_2 \xrightarrow{CuCl_2, 250^\circ C} C_6H_5-Cl + H_2O$ 63. Wurtz-Fittig Reaction $Ar-X + R-X + 2Na \xrightarrow{ether} Ar-R + 2NaX$ Forms alkylarenes. 64. Fittig Reaction $2Ar-X + 2Na \xrightarrow{ether} Ar-Ar + 2NaX$ Forms biaryls (e.g., biphenyl). 65. Ullmann's Biaryl Synthesis $2Ar-I \xrightarrow{Cu/\Delta} Ar-Ar + CuI_2$ 66. Formation of DDT Chloral ($CCl_3CHO$) + 2 Chlorobenzene $\xrightarrow{Conc. H_2SO_4} DDT$ DDT: Dichlorodiphenyltrichloroethane, an insecticide. 67. Reaction of Aldehydes & Ketones with Grignard Reagent Formaldehyde ($HCHO$) + $RMgX \xrightarrow{H_3O^+} R-CH_2-OH$ ($1^\circ$ alcohol) Aldehyde ($R'CHO$) + $RMgX \xrightarrow{H_3O^+} R-CH(OH)-R'$ ($2^\circ$ alcohol) Ketone ($R'COR''$) + $RMgX \xrightarrow{H_3O^+} R-C(OH)(R')(R'')$ ($3^\circ$ alcohol) 68. Reactions with Carboxylic Acid & Derivatives with Grignard Reagent Carboxylic acid ($RCOOH$) + $R'MgX \rightarrow R'-H + Mg(OCOR)X$ (acid-base reaction) Ester ($R-COOR''$) + $2R'MgX \rightarrow R-C(OH)(R')_2$ ($3^\circ$ alcohol) Acid chloride ($R-COCl$) + $2R'MgX \rightarrow R-C(OH)(R')_2$ ($3^\circ$ alcohol) $CO_2 + RMgX \xrightarrow{H_3O^+} R-COOH$ 69. Reaction of Alcohol with Ammonia $ROH + NH_3 \xrightarrow{Al_2O_3/\Delta} R-NH_2$ 70. Reaction of Alcohol with Diazomethane $ROH + CH_2N_2 \rightarrow R-O-CH_3 + N_2$ 71. Pinacol-Pinacolone Rearrangement Pinacol (vicinal diol) $\xrightarrow{H_2SO_4 \text{ or } H^+} Pinacolone$ (ketone) Involves carbocation formation and 1,2-shift (migratory aptitude: $Ar > H > 3^\circ > 2^\circ > 1^\circ$). 72. Lucas Test $ROH + HCl/ZnCl_2 \rightarrow R-Cl$ (turbidity) $3^\circ$ alcohol: Immediate turbidity. $2^\circ$ alcohol: Turbidity in 5-10 minutes. $1^\circ$ alcohol: No turbidity at room temperature. 73. Victor Meyer Test $1^\circ$ alcohol: Red color (nitrolic acid). $2^\circ$ alcohol: Blue color (pseudonitrole). $3^\circ$ alcohol: Colorless. 74. From Cumene Hydroperoxide (Best method for Phenol) Cumene ($C_6H_5-CH(CH_3)_2$) $\xrightarrow{O_2/120^\circ C} Cumene \text{ hydroperoxide}$ $\xrightarrow{H_3O^+} Phenol + Acetone$ 75. Formation of Aspirin Salicylic acid + Acetic anhydride $\xrightarrow{H_3PO_4/\Delta} Aspirin$ (Acetylsalicylic acid) 76. Schotten-Baumann Reaction Phenol + Benzoyl chloride $\xrightarrow{NaOH/H_2O} Phenyl \text{ benzoate}$ 77. Reimer-Tiemann Reaction Phenol + $CHCl_3 + NaOH \rightarrow Salicylaldehyde$ ( o -isomer is major due to intramolecular H-bonding) 78. Claisen Rearrangement Aryl allyl ethers $\xrightarrow{200^\circ C} o\text{-allylphenol}$ Pericyclic reaction (Ene reaction). 79. Liebermann's Nitro Test Phenol + $NaNO_2/H_2SO_4 \rightarrow$ Red color (p-nitrosophenol) $\xrightarrow{NaOH} Blue \text{ color (indophenol)}$ 80. Formation of Alkyl-Aryl Ethers (Williamson Synthesis) Phenol + $NaOH \rightarrow C_6H_5O^-Na^+ \xrightarrow{R-X} C_6H_5-O-R$ 81. Reaction of Phenol with Diazomethane $C_6H_5-OH + CH_2N_2 \rightarrow C_6H_5-O-CH_3 + N_2$ 82. Hydrogenation of Phenol $C_6H_5-OH + 3H_2 \xrightarrow{Ni, 150-250^\circ C} Cyclohexanol$ 83. Preparation of Phenolphthalein Phenol + Phthalic anhydride $\xrightarrow{Conc. H_2SO_4} Phenolphthalein$ 84. Oxidation of Phenols Elbs Persulphate Oxidation: Phenol $\xrightarrow{K_2S_2O_8 \text{ (alkaline)}} Hydroquinone$ Phenol $\xrightarrow{K_2Cr_2O_7/H_2SO_4} p\text{-Benzoquinone}$ 85. Bromination of Phenol Phenol + $Br_2/CS_2 \rightarrow o\text{- and } p\text{-Bromophenol}$ Phenol + $Br_2/H_2O \rightarrow 2,4,6\text{-Tribromophenol (white ppt)}$ 86. Kolbe's Reaction Phenol + $CO_2 \xrightarrow{NaOH, \text{ high P, T}} Salicylic \text{ acid}$ 87. Diazocoupling Reaction Phenol + Benzene diazonium chloride $\rightarrow p\text{-Hydroxyazobenzene (azo dye)}$ 88. Dienone-Phenol Rearrangement Dienone $\xrightarrow{H^+} Phenol$ 89. Lederer-Manasse Reaction (Formation of Bakelite) Phenol + Formaldehyde $\xrightarrow{H^+ \text{ or } OH^-} Novolac \text{ (linear)} \xrightarrow{\text{cross-linking}} Bakelite \text{ (thermosetting polymer)}$ 90. Test of Phenols Phenol + Neutral $FeCl_3 \rightarrow$ Violet color. 91. Intermolecular Dehydration of Alcohols $2R-CH_2-OH \xrightarrow{Conc. H_2SO_4, 140^\circ C} R-CH_2-O-CH_2-R$ (Ether) Goes via $S_N2$ (for $1^\circ$) or E1 (for $3^\circ$). 92. Williamson's Ether Synthesis $R-O^-Na^+ + R'-X \rightarrow R-O-R' + NaX$ For better yield, $R'-X$ should be $CH_3-X$ or $1^\circ$ alkyl halide (to avoid E2). 93. Reaction of R-X with Dry $Ag_2O$ $2R-X + Ag_2O \xrightarrow{dry} R-O-R + 2AgX$ 94. From Grignard Reagent (Ethers) $R-MgX + R'-O-R'' \rightarrow R-R'' + R'-O-MgX$ (ether cleavage, less common) 95. Reaction of Ethers with HX $R-O-R' + HX \rightarrow R-OH + R'-X$ (cleavage) Reactivity of HX: $HI > HBr > HCl$. For unsymmetrical ethers, the halide goes to the more stable carbocation if $S_N1$ (e.g., $3^\circ$). If $S_N2$, it goes to the less hindered carbon. 96. From Glycerol (Reaction with HI) Glycerol + $HI \rightarrow Allyl \text{ iodide}$ (vicinal iodides are unstable) $\rightarrow Propene$ 97. Reaction of Glycerol with Nitric Acid Glycerol + $3HNO_3 \xrightarrow{Conc. H_2SO_4} Glyceryl \text{ trinitrate (nitroglycerine, explosive)}$ 98. Reaction of Glycerol with Oxalic Acid Glycerol + Oxalic acid $\xrightarrow{110^\circ C} Glyceryl \text{ monoformate}$ $\xrightarrow{-\text{CO}_2} Allyl \text{ alcohol}$ 99. Reaction of Glycerol with $KHSO_4/Conc. H_2SO_4/P_2O_5$ (Dehydration) Glycerol $\xrightarrow{KHSO_4} Acrolein$ (Propenal) 100. Oxidation of Alcohols $1^\circ$ alcohol $\rightarrow$ Aldehyde $\rightarrow$ Carboxylic acid $2^\circ$ alcohol $\rightarrow$ Ketone $3^\circ$ alcohol $\rightarrow$ No oxidation under normal conditions. 101. Dehydrogenation over Heated Copper $1^\circ$ alcohol $\xrightarrow{Cu, 300^\circ C} Aldehyde$ $2^\circ$ alcohol $\xrightarrow{Cu, 300^\circ C} Ketone$ $3^\circ$ alcohol $\xrightarrow{Cu, 300^\circ C} Alkene$ (dehydration) 102. Oxidation with PCC (Pyridinium Chlorochromate) $1^\circ$ alcohol $\rightarrow$ Aldehyde $2^\circ$ alcohol $\rightarrow$ Ketone $3^\circ$ alcohol $\rightarrow$ No reaction (generally) Does not affect multiple bonds. 103. From PDC (Pyridinium Dichromate) $1^\circ$ alcohol $\rightarrow$ Aldehyde $2^\circ$ alcohol $\rightarrow$ Ketone $3^\circ$ alcohol $\rightarrow$ No reaction Does not affect other functional groups. Non-conjugated $1^\circ$ alcohols are oxidized to carboxylic acids if water is present. 104. From Collin's Reagent ($CrO_3 \cdot 2Pyridine$) $1^\circ$ alcohol $\rightarrow$ Aldehyde $2^\circ$ alcohol $\rightarrow$ Ketone $3^\circ$ alcohol $\rightarrow$ Not affected 105. From Jones Reagent ($CrO_3/H_2SO_4$ in Acetone) $1^\circ$ alcohol $\rightarrow$ Aldehyde $\rightarrow$ Carboxylic acid $2^\circ$ alcohol $\rightarrow$ Ketone $3^\circ$ alcohol $\rightarrow$ No reaction Multiple bonds $\rightarrow$ Not affected. 106. From Acidified $KMnO_4$ (Strong Oxidizing Agent) $1^\circ$ alcohol $\rightarrow$ Carboxylic acid $2^\circ$ alcohol $\rightarrow$ Ketone $\rightarrow$ Carboxylic acids (by C-C bond cleavage, Popoff's Rule) $3^\circ$ alcohol $\rightarrow$ No reaction. Multiple bonds are oxidized (oxidative cleavage). 107. From $MnO_2$ (Allylic Oxidation) Specific for benzylic and allylic alcohols. Allylic alcohol $\rightarrow$ Acrolein Benzylic alcohol $\rightarrow$ Benzaldehyde 108. Oxidation with $SeO_2$ Oxidizes allylic alcohols to carbonyl compounds. Oxidizes methylene groups between two aromatic rings to carbonyl. Oxidation of alkynes to $\alpha$-diketones. Oxidation of ketones at $\alpha$-position to $\alpha$-keto aldehydes. 109. Oppenauer Oxidation $2^\circ$ alcohol + Ketone (excess) $\xrightarrow{Al(t-BuO)_3} Ketone + 2^\circ \text{ alcohol}$ Reverse of Meerwein-Ponndorf-Verley reduction. 110. Swern Oxidation $R-CH_2-OH + (CH_3)_2S-O + (COCl)_2 \xrightarrow{Et_3N} R-CHO + (CH_3)_2S + CO_2 + HCl$ 111. From $Ag_2CO_3/C_6H_6$ (Oppenauer type) $1^\circ$ alcohol $\rightarrow$ Aldehyde $2^\circ$ alcohol $\rightarrow$ Ketone $3^\circ$ alcohol $\rightarrow$ Not affected. Allylic bromination. 112. Oxidation with $HIO_4$ (Periodic Acid) Cleaves vicinal diols to carbonyl compounds. 113. LTA (Lead Tetraacetate) Works similar to $HIO_4$, cleaves vicinal diols. 114. From CAN (Ceric Ammonium Nitrate) Cleaves vicinal diols. 115. Bayer-Villiger Oxidation Ketone + Peracid $\rightarrow$ Ester Aldehyde + Peracid $\rightarrow$ Carboxylic acid Migratory aptitude: $3^\circ > 2^\circ > 1^\circ > CH_3$ 116. Popoff's Rule In the oxidation of unsymmetrical ketones, the C-C bond cleavage occurs such that the carbonyl group remains with the smaller alkyl group (usually). 117. Heating Effect of Dicarboxylic Acids Oxalic acid ($n=0$): $\xrightarrow{\Delta} H_2O + CO_2 + CO$ Malonic acid ($n=1$): $\xrightarrow{\Delta} CH_3COOH + CO_2$ Succinic acid ($n=2$): $\xrightarrow{\Delta} Succinic \text{ anhydride}$ Glutaric acid ($n=3$): $\xrightarrow{\Delta} Glutaric \text{ anhydride}$ Adipic acid ($n=4$): $\xrightarrow{\Delta} Cyclopentanone + CO_2 + H_2O$ (intramolecular condensation) Phthalic acid: $\xrightarrow{\Delta} Phthalic \text{ anhydride}$ Maleic acid: $\xrightarrow{\Delta} Maleic \text{ anhydride}$ 118. Heating Effect of $\beta$-keto Acids $\beta$-keto acid $\xrightarrow{\Delta} Ketone + CO_2$ Electron-withdrawing groups at $\alpha$-position increase the rate of decarboxylation. 119. By Passing Vapors of Carboxylic Acid over Heated $MnO$ $2R-COOH \xrightarrow{MnO, 300^\circ C} R-CO-R + CO_2 + H_2O$ (Symmetrical ketone) $R-COOH + R'-COOH \xrightarrow{MnO, 300^\circ C} R-CO-R'$ (Unsymmetrical ketone) 120. Heating Effect of Calcium or Barium Salt of Carboxylic Acids $(R-COO)_2Ca \xrightarrow{\Delta} R-CO-R + CaCO_3$ 121. Oxo Process (Hydroformylation) $R-CH=CH_2 + CO + H_2 \xrightarrow{Co_2(CO)_8} R-CH_2-CH_2-CHO$ (Aldehyde) 122. Cyanohydrin Formation $C=O + HCN \rightarrow C(OH)-CN$ Hydrolysis of cyanohydrin gives $\alpha$-hydroxy carboxylic acid. 123. Reaction of Formaldehyde with Ammonia $6HCHO + 4NH_3 \rightarrow (CH_2)_6N_4$ (Hexamethylenetetramine, Urotropine) 124. Reaction of Carbonyl Compounds with Ammonia Derivatives $C=O + H_2N-Z \rightarrow C=N-Z + H_2O$ Hydroxylamine ($H_2N-OH$) $\rightarrow$ Oxime Hydrazine ($H_2N-NH_2$) $\rightarrow$ Hydrazone Phenylhydrazine ($H_2N-NH-Ph$) $\rightarrow$ Phenylhydrazone 2,4-Dinitrophenylhydrazine (Brady's Reagent) $\rightarrow$ 2,4-Dinitrophenylhydrazone (orange-red/yellow ppt, test for aldehydes & ketones) 125. Reaction with $PCl_5$ (Carbonyls) $C=O + PCl_5 \rightarrow C(Cl)_2 + POCl_3$ 126. Formation of Acetals and Hemiacetals Aldehyde/Ketone + $ROH \xrightarrow{H^+} Hemiacetal$ (unstable in acid) Hemiacetal + $ROH \xrightarrow{H^+} Acetal$ (unstable in acid, stable in base) 127. Reduction by Dissolving Metals (Pinacol Formation) $2R-CO-R \xrightarrow{Na/EtOH} R-CH(OH)-CH(OH)-R$ (Pinacol) $2R-CO-R \xrightarrow{Mg(Hg)/H_2O} R-C(OH)(R)-C(OH)(R)-R$ (Pinacol) 128. Bouveault-Blanc Reduction Ester ($R-COOR'$) $\xrightarrow{Na/EtOH} R-CH_2-OH + R'-OH$ 129. Reduction with $LiAlH_4$ (LAH) Strong reducing agent, reduces: Aldehydes $\rightarrow 1^\circ$ alcohols Ketones $\rightarrow 2^\circ$ alcohols Carboxylic acids $\rightarrow 1^\circ$ alcohols Esters $\rightarrow$ Mixture of alcohols Amides $\rightarrow$ Amines Nitro compounds $\rightarrow$ Amines Nitriles $\rightarrow$ Amines Epoxides $\rightarrow$ Alcohols Alkyl halides $\rightarrow$ Alkanes 130. Reduction with LTTBAH (Lithium Tritertbutoxyaluminum Hydride) Weaker reducing agent than LAH. Reduces acid chlorides to aldehydes. 131. Reduction with $NaBH_4$ (Sodium Borohydride) Weaker than LAH. Reduces: Aldehydes $\rightarrow 1^\circ$ alcohols Ketones $\rightarrow 2^\circ$ alcohols Does not reduce esters, amides, carboxylic acids, nitro compounds, nitriles, alkenes, alkynes. 132. Reduction with $B_2H_6$ Reduces: Carboxylic acids $\rightarrow 1^\circ$ alcohols Nitriles $\rightarrow$ Amines Alkenes $\rightarrow$ Alkanes (Hydroboration-reduction) 133. Reduction with DIBAL-H (Diisobutylaluminum Hydride) Reduces: Esters $\rightarrow$ Aldehydes (at low temperature) Nitriles $\rightarrow$ Aldehydes (at low temperature) Carboxylic acids $\rightarrow$ Aldehydes (at low temperature) 134. Reduction with 9-BBN (9-Borabicyclo[3.3.1]nonane) Used for selective reduction of alkenes to alcohols (anti-Markovnikov). 135. Birch Reduction (Aromatic Ring) Aromatic ring $\xrightarrow{Na/Liq. NH_3, EtOH} 1,4\text{-cyclohexadiene}$ 136. Stephen's Reduction Nitrile ($R-C \equiv N$) $\xrightarrow{SnCl_2/HCl} R-CH=NH \xrightarrow{H_3O^+} R-CHO$ (Aldehyde) 137. Rosenmund Reduction Acid chloride ($R-COCl$) $\xrightarrow{H_2/Pd-BaSO_4/\text{S-Quinoline}} R-CHO$ (Aldehyde) 138. Aldol Reaction and Condensation Aldehyde/Ketone with $\alpha$-H $\xrightarrow{dil. OH^-} \beta\text{-hydroxy aldehyde/ketone}$ (Aldol reaction) $\beta\text{-hydroxy aldehyde/ketone} \xrightarrow{\Delta} \alpha,\beta\text{-unsaturated aldehyde/ketone}$ (Aldol condensation) Intramolecular aldol condensation forms cyclic products. Cross aldol condensation: One reactant must be non-enolizable. Aldol reaction can also occur in acidic medium. 139. Claisen Condensation Ester with $\alpha$-H $\xrightarrow{NaOEt/EtOH} \beta\text{-ketoester}$ Intramolecular Claisen condensation is called Dieckmann cyclization . 140. Knoevenagel Condensation Aldehyde/Ketone + Active methylene compound (e.g., malonic ester) $\xrightarrow{Weak \text{ base}} \alpha,\beta\text{-unsaturated compound}$ 141. Michael Addition (Conjugate Addition) Nucleophile + $\alpha,\beta\text{-unsaturated carbonyl compound} \rightarrow 1,4\text{-adduct}$ Michael donor: compounds with active methylene groups. Michael acceptor: $\alpha,\beta\text{-unsaturated carbonyl compounds}$. 142. Reformatsky Reaction Aldehyde/Ketone + $\alpha$-Bromoester $\xrightarrow{Zn/ether, H_3O^+} \beta\text{-hydroxyester}$ 143. Beckmann Rearrangement Oxime $\xrightarrow{H^+ \text{ or Lewis acid}} N\text{-alkylamide}$ Migrating group is anti to the -OH group. 144. Benzil-Benzilic Acid Rearrangement Benzil ($\alpha$-diketone) $\xrightarrow{OH^-} Benzilic \text{ acid}$ ($\alpha$-hydroxy carboxylic acid) Involves 1,2-shift of an aryl group. 145. Cannizzaro Reaction Aldehyde without $\alpha$-H $\xrightarrow{Conc. OH^-} Carboxylic \text{ acid salt} + Alcohol$ Disproportionation reaction (self-oxidation and reduction). Cross Cannizzaro: One reactant must be non-enolizable. Intramolecular Cannizzaro: Dialdehydes without $\alpha$-H. 146. Perkin Reaction Aromatic aldehyde + Acid anhydride (with $\alpha$-H) $\xrightarrow{Sodium \text{ salt of acid}} \alpha,\beta\text{-unsaturated carboxylic acid}$ (e.g., Cinnamic acid) 147. Haloform Reaction Methyl ketone ($R-CO-CH_3$) or Acetaldehyde ($CH_3CHO$) or $2^\circ$ alcohol ($R-CH(OH)-CH_3$) $\xrightarrow{X_2/NaOH} CHX_3 + R-COONa$ $CHI_3$ (iodoform) is a yellow solid (test). 148. Tischenko Reaction $2R-CHO \xrightarrow{Al(OEt)_3} R-COO-CH_2-R$ (Ester) 149. Benzoin Condensation $2Ar-CHO \xrightarrow{KCN} Ar-CH(OH)-CO-Ar$ (Benzoin) 150. Schmidt Reaction Carboxylic acid ($R-COOH$) + Hydrazoic acid ($HN_3$) $\xrightarrow{H_2SO_4} R-NH_2 + CO_2 + N_2$ 151. Curtius Rearrangement Acyl azide ($R-CON_3$) $\xrightarrow{\Delta} R-N=C=O \xrightarrow{H_2O} R-NH_2 + CO_2$ 152. Lossen Rearrangement Hydroxamic ester ($R-CONH-OR'$) $\xrightarrow{\Delta \text{ or } OH^-} R-N=C=O \xrightarrow{H_2O} R-NH_2 + CO_2$ 153. Hoffmann Bromamide Degradation Amide ($R-CONH_2$) $\xrightarrow{Br_2/KOH} R-NH_2 + K_2CO_3 + KBr + H_2O$ Decreases carbon chain length by one carbon. 154. Gattermann-Koch Reaction Benzene + $CO + HCl \xrightarrow{AlCl_3/CuCl} Benzaldehyde$ 155. Gattermann Reaction (Aldehyde Synthesis) Benzene + $HCN + HCl \xrightarrow{AlCl_3} Benzaldehyde$ 156. Acyloin Condensation $2R-COOR' \xrightarrow{Na/ether, H_3O^+} R-CH(OH)-CO-R$ ($\alpha$-hydroxy ketone) 157. Wolff Rearrangement $\alpha$-Diazoketone ($R-CO-CH_2-N_2$) $\xrightarrow{\Delta \text{ or } Ag_2O/\Delta} R-CH=C=O$ (Ketene) Ketene $\xrightarrow{H_2O} R-CH_2-COOH$ (Carboxylic acid) Ketene $\xrightarrow{ROH} R-CH_2-COOR$ (Ester) Ketene $\xrightarrow{NH_3} R-CH_2-CONH_2$ (Amide) 158. Gabriel Phthalimide Synthesis Phthalimide $\xrightarrow{KOH} K^+\text{ phthalimide anion} \xrightarrow{R-X} N\text{-alkylphthalimide} \xrightarrow{H_3O^+ \text{ or } N_2H_4} R-NH_2 + Phthalic \text{ acid}$ Best method to prepare $1^\circ$ amines. Cannot prepare $3^\circ$ amines or aryl amines. 159. Carbylamine Reaction (Isocyanide Test) $1^\circ$ amine ($R-NH_2$) + $CHCl_3 + KOH \xrightarrow{\Delta} R-N \equiv C$ (Alkyl isocyanide, foul smell) Test for $1^\circ$ amines. 160. Reaction of Acetaldehyde with Conc. $H_2SO_4$ $3CH_3CHO \xrightarrow{Conc. H_2SO_4} Paraldehyde$ (Cyclic trimer) $4CH_3CHO \xrightarrow{Conc. H_2SO_4} Metaldehyde$ (Cyclic tetramer) 161. Reaction of Acetone with Conc. $H_2SO_4$ $3CH_3COCH_3 \xrightarrow{Conc. H_2SO_4} Mesitylene$ (1,3,5-Trimethylbenzene) 162. Silver Mirror Test (Tollen's Reagent) Aldehyde ($R-CHO$) $\xrightarrow{[Ag(NH_3)_2]^+OH^-} R-COO^- + Ag \downarrow$ (Silver mirror) Reduces Tollen's reagent. 163. Fehling's Solution Test Aldehyde ($R-CHO$) $\xrightarrow{Cu^{2+}/OH^-} R-COO^- + Cu_2O \downarrow$ (Red precipitate) 164. Benedict's Solution Test Similar to Fehling's, uses citrate complexed $Cu^{2+}$. 165. Schiff's Reagent Test Aldehydes restore the magenta color of Schiff's reagent. Ketones generally do not respond. 166. Reaction of Carboxylic Acid with Excess RLi $R-COOH + 2RLi \rightarrow R-C(OLi)_2-R' \xrightarrow{H_3O^+} R-CO-R'$ (Ketone) 167. Conversion of Carboxylic Acid to Derivatives $R-COOH \xrightarrow{PCl_5/PCl_3/SOCl_2} R-COCl$ (Acid chloride) $R-COOH + R'-OH \xrightarrow{H^+} R-COOR'$ (Ester, Esterification) $R-COOH + CH_2N_2 \rightarrow R-COOCH_3 + N_2$ (Ester) $R-COOH \xrightarrow{NH_3/\Delta} R-CONH_2$ (Amide) $R-CONH_2 \xrightarrow{P_2O_5} R-C \equiv N$ (Nitrile) 168. Reaction of Acetic Acid with Conc. $H_2SO_4$ $CH_3COOH \xrightarrow{Conc. H_2SO_4} Ketene + H_2O$ (dehydration) 169. Heating Effect of $\alpha, \beta, \gamma, \delta$-hydroxy Carboxylic Acids $\alpha$-hydroxy acid: Intermolecular dehydration to lactide. $\beta$-hydroxy acid: Dehydration to $\alpha,\beta$-unsaturated acid. $\gamma$-hydroxy acid: Intramolecular esterification to $\gamma$-lactone. $\delta$-hydroxy acid: Intramolecular esterification to $\delta$-lactone. 170. Test of Carboxylic Acids (with $NaHCO_3$) Carboxylic acids react with $NaHCO_3$ to give $CO_2$ effervescence. Some phenols (stronger than picric acid) also give $CO_2$. 171. Test of Formic Acid Formic acid reduces Tollen's and Fehling's solutions. 172. Cacodyl Test Acetate salts $\xrightarrow{As_2O_3} Cacodyl \text{ oxide}$ (foul-smelling, poisonous) 173. Reactions of Acid Chlorides $R-COCl \xrightarrow{NH_3} R-CONH_2$ (Amide) $R-COCl \xrightarrow{R'OH} R-COOR'$ (Ester) $R-COCl \xrightarrow{R_2CuLi} R-CO-R'$ (Ketone) $R-COCl \xrightarrow{KCN} R-CO-CN$ (Acyl cyanide) 174. Reactions of Amides $R-CONH_2 \xrightarrow{P_2O_5} R-C \equiv N$ (Nitrile) $R-CONH_2 \xrightarrow{HNO_2} R-COOH$ 175. Alkylation of Amines $NH_3 + R-X \rightarrow R-NH_2 \xrightarrow{R-X} R_2NH \xrightarrow{R-X} R_3N \xrightarrow{R-X} R_4N^+X^-$ $S_N2$ reaction. 176. Reaction of R-X with Azide ($N_3^-$) Ion $R-X + NaN_3 \rightarrow R-N_3 \xrightarrow{LAH \text{ or } H_2/EtOH} R-NH_2$ 177. Reduction of Nitro Compounds $R-NO_2 \xrightarrow{H_2/Ni} R-NH_2 + H_2O$ $R-NO_2 \xrightarrow{Sn/HCl \text{ or } Fe/HCl} R-NH_2$ (Acidic medium) $R-NO_2 \xrightarrow{Fe/Steam \text{ or } Zn/NH_4Cl} R-NH_2$ (Neutral medium) 178. Hofmann Mustard Oil Reaction $R-NH_2 + CS_2 \rightarrow Dithiocarbamic \text{ acid salt} \xrightarrow{HgCl_2} R-N=C=S$ (Alkyl isothiocyanate, mustard oil smell) 179. Reaction of Primary Amines with $HNO_2$ $1^\circ$ amine ($R-NH_2$) $\xrightarrow{NaNO_2/HCl} R-OH + N_2 \uparrow + HCl$ 180. Reaction of Secondary Amines with $HNO_2$ $2^\circ$ amine ($R_2NH$) $\xrightarrow{NaNO_2/HCl} R_2N-N=O$ (N-Nitrosamine, yellow oily liquid) 181. Reaction of Tertiary Amines with $HNO_2$ $3^\circ$ amine ($R_3N$) + $HNO_2 \rightarrow$ No reaction. 182. Oxidation of Amines $1^\circ$ amine $\xrightarrow{KMnO_4} Aldimine \rightarrow Aldehyde$ $1^\circ$ amine $\xrightarrow{H_2SO_5 \text{ or } H_2O_2} R-CH_2-NH-OH$ (Hydroxylamine) $\rightarrow$ Aldoxime $2^\circ$ amine $\xrightarrow{H_2SO_5 \text{ or } H_2O_2} R_2N-OH$ (N,N-Dialkylhydroxylamine) $3^\circ$ amine $\xrightarrow{H_2SO_5 \text{ or } H_2O_2} R_3N \rightarrow R_3N^+-O^-$ (Amine oxide) 183. Hinsberg's Test Benzenesulphonyl chloride + $1^\circ$ amine $\rightarrow$ Sulphonamide (soluble in KOH) Benzenesulphonyl chloride + $2^\circ$ amine $\rightarrow$ Sulphonamide (insoluble in KOH) Benzenesulphonyl chloride + $3^\circ$ amine $\rightarrow$ No reaction. 184. Reaction with Diethyl Oxalate $1^\circ$ amine + Diethyl oxalate $\rightarrow$ Oxamide (solid) $2^\circ$ amine + Diethyl oxalate $\rightarrow$ Oxamic ester (liquid) 185. Preparation of Amino Acids (HVZ Reaction) $R-CH_2-COOH \xrightarrow{P+Br_2} R-CH(Br)-COOH \xrightarrow{Excess \text{ NH}_3} R-CH(NH_2)-COOH$ 186. Strecker's Synthesis (Amino Acids) Aldehyde ($RCHO$) + $NH_3 + HCN \rightarrow R-CH(NH_2)-CN \xrightarrow{H_3O^+} R-CH(NH_2)-COOH$