Oxygen-Containing Organic Compounds Formula Sheet

This chapter is reaction-driven, not formula-driven. The sheet below is a scannable round-up of the key relations, reagents, name reactions, acidity orders, and qualitative tests pulled straight from the alcohols, phenols, ethers, aldehydes & ketones, and carboxylic acids topics. Use it for last-minute revision.

How to use this sheet

Most “formulas” here are reactivity orders, reagent-product pairs, and qualitative tests. Memorise the boxed orders and the test tables — that is where JEE marks come from in this chapter.

Functional Groups at a Glance

Class	General formula	Key feature
Alcohol	$\text{R-OH}$	-OH on sp³ carbon
Phenol	$\text{C}_6\text{H}_5\text{-OH}$	-OH on sp² (aromatic) carbon
Ether	$\text{R-O-R}'$	O bridging two carbons, no H on O
Aldehyde	$\text{R-CHO}$	C=O terminal, ≥1 H on carbonyl C
Ketone	$\text{R-CO-R}'$	C=O internal, no H on carbonyl C
Carboxylic acid	$\text{R-COOH}$	carbonyl + hydroxyl = carboxyl

graph TD
    A[Oxygen Compounds] --> B[Alcohols and Phenols]
    A --> C[Ethers]
    A --> D[Carbonyl Compounds]
    A --> E[Carboxylic Acids]
    D --> D1[Aldehydes]
    D --> D2[Ketones]

Alcohols

Classification and reactivity

Class	Structure	Carbons on C-OH
Primary (1°)	$\text{R-CH}_2\text{-OH}$	1
Secondary (2°)	$\text{R}_2\text{CH-OH}$	2
Tertiary (3°)	$\text{R}_3\text{C-OH}$	3

$$\boxed{\text{SN1 / E1 reactivity: } 3° > 2° > 1° \quad (\text{carbocation stability})}$$$$\boxed{\text{SN2 reactivity: } 1° > 2° > 3° \quad (\text{steric hindrance})}$$$$\boxed{\text{Acidity: } \text{H}_2\text{O} > 1° > 2° > 3° \quad (+\text{I effect destabilises RO}^-)}$$

Preparation

Method	Reagent	Product
Markovnikov hydration	$\text{H}_2\text{SO}_4/\text{H}_2\text{O}$	more-substituted alcohol (2°/3°)
Anti-Markovnikov	$\text{BH}_3/\text{THF}$, then $\text{H}_2\text{O}_2/\text{OH}^-$	less-substituted (1°) alcohol
Aldehyde reduction	$\text{LiAlH}_4$ or $\text{NaBH}_4$	1° alcohol
Ketone reduction	$\text{LiAlH}_4$ or $\text{NaBH}_4$	2° alcohol
Ester / acid reduction	$\text{LiAlH}_4$ (not $\text{NaBH}_4$)	1° alcohol
Hydrolysis of R-X	aq. NaOH/KOH	alcohol

Grignard pattern (carbonyl + RMgX, then H₃O⁺):

Carbonyl	Product
Formaldehyde (HCHO)	1° alcohol
Other aldehyde (R′CHO)	2° alcohol
Ketone (R′COR″)	3° alcohol
Ester (2 RMgX)	3° alcohol (two identical R)

Key reactions

$$\boxed{\text{Reactivity with HX: } \text{HI} > \text{HBr} > \text{HCl}; \quad 3° > 2° > 1°}$$

Dehydration (conc. H₂SO₄): $140°\text{C} \rightarrow$ ether; $170°\text{C} \rightarrow$ alkene (Saytzeff: more-substituted alkene major).
With Na: $2\,\text{R-OH} + 2\,\text{Na} \rightarrow 2\,\text{R-O}^-\text{Na}^+ + \text{H}_2\uparrow$ (effervescence = -OH test).
Esterification (Fischer, reversible): $\text{R-OH} + \text{R}'\text{COOH} \underset{\text{conc. H}_2\text{SO}_4}{\rightleftharpoons} \text{R}'\text{COO-R} + \text{H}_2\text{O}$.

Oxidation outcomes:

Alcohol	PCC (mild)	$\text{K}_2\text{Cr}_2\text{O}_7/\text{H}^+$ (strong)
1°	aldehyde	carboxylic acid
2°	ketone	ketone (stops)
3°	no reaction	no reaction

Carbocation rearrangement

For 2°/3° alcohols going through SN1/E1, watch for hydride or methyl shifts that convert a 2° carbocation into a more stable 3° one before the nucleophile attacks.

Lucas test (HCl + ZnCl₂)

Alcohol	Turbidity
3°	immediate
2°	~5 minutes
1°	none at room temp

Phenols

Acidity

$$\boxed{\text{R-COOH} \gg \text{PhOH} > \text{H}_2\text{O} > \text{R-OH}}$$$$\boxed{\text{p}K_a: \text{RCOOH }(4\text{-}5) \ll \text{PhOH }(10) < \text{H}_2\text{O }(15.7) < \text{ROH }(16)}$$

Phenol is acidic because the phenoxide ion is resonance-stabilised (charge delocalised into the ring).

Substituent effect on acidity:

$$\boxed{p\text{-NO}_2\text{-C}_6\text{H}_4\text{OH} > m\text{-NO}_2\text{-C}_6\text{H}_4\text{OH} > \text{C}_6\text{H}_5\text{OH} > p\text{-CH}_3\text{-C}_6\text{H}_4\text{OH}}$$

EWG (-NO₂, -CN, -CHO, -X) increase acidity; ortho/para > meta (direct resonance).
EDG (-CH₃, -OCH₃, -NH₂) decrease acidity.

Preparation

Method	Conditions
Dow process (from $\text{C}_6\text{H}_5\text{Cl}$)	NaOH(aq), 623 K, 350 atm, then H⁺
Alkali fusion (from $\text{C}_6\text{H}_5\text{SO}_3\text{H}$)	fused NaOH, 623 K, then H⁺
Diazonium hydrolysis	$\text{C}_6\text{H}_5\text{N}_2^+\text{Cl}^- + \text{H}_2\text{O} \xrightarrow{\text{warm}} \text{C}_6\text{H}_5\text{OH} + \text{N}_2 + \text{HCl}$
Cumene process	$\text{O}_2$ then $\text{H}^+$ → phenol + acetone

Diazonium salt is stable only at 0–5 °C; aniline → diazonium uses NaNO₂ + HCl at 0–5 °C.

Electrophilic substitution (ortho/para, often no catalyst)

Reagent	Product	Note
dil. $\text{HNO}_3$	o-/p-nitrophenol	no catalyst needed
conc. $\text{HNO}_3/\text{H}_2\text{SO}_4$	picric acid (2,4,6-trinitrophenol)	explosive
$\text{Br}_2/\text{H}_2\text{O}$	2,4,6-tribromophenol	white ppt — test for phenol
$\text{Br}_2/\text{CS}_2$	mono-bromophenol	non-polar solvent
conc. $\text{H}_2\text{SO}_4$	phenolsulfonic acid	100 °C → ortho, higher T → para

Name reactions

Kolbe (Kolbe–Schmitt): sodium phenoxide $+\,\text{CO}_2$ (400 K, 4–7 atm), then H⁺ → salicylic acid (ortho-COOH).
Reimer–Tiemann: phenol $+\,\text{CHCl}_3/\text{NaOH}$ → salicylaldehyde (ortho-CHO); proceeds via dichlorocarbene :CCl₂.
Azo coupling: phenol $+\,\text{C}_6\text{H}_5\text{N}_2^+\text{Cl}^-$ (NaOH, 273 K) → p-hydroxyazobenzene (orange dye).

Tests and contrasts

Test	Phenol	Alcohol	RCOOH
Neutral $\text{FeCl}_3$	violet/blue ✓	no colour	—
NaOH	dissolves ✓	no reaction	dissolves
$\text{NaHCO}_3$	no reaction	no reaction	$\text{CO}_2\uparrow$ ✓

$$3\,\text{C}_6\text{H}_5\text{OH} + \text{FeCl}_3 \rightarrow [\text{Fe(OC}_6\text{H}_5)_3] + 3\,\text{HCl}$$

High-yield distinction

Benzyl alcohol ($\text{C}_6\text{H}_5\text{-CH}_2\text{-OH}$) is an alcohol, NOT a phenol — no FeCl₃ colour, no Br₂/H₂O ppt. Phenol esterification needs an acid chloride or anhydride (not Fischer with RCOOH), because the C-O bond has partial double-bond character.

Ethers

Physical properties

$$\boxed{\text{Boiling point (similar MW): Alcohol} > \text{Ether} > \text{Alkane}}$$

Ethers: no O-H, so no H-bond donation (only dipole-dipole); they can accept H-bonds → small ethers slightly water-soluble.

Preparation

Method	Reaction	Note
Williamson synthesis	$\text{R-O}^-\text{Na}^+ + \text{R}'\text{-X} \rightarrow \text{R-O-R}' + \text{NaX}$	SN2; use 1° alkyl halide
Dehydration (symmetrical only)	$2\,\text{R-OH} \xrightarrow{\text{conc. H}_2\text{SO}_4,\,140°\text{C}} \text{R-O-R} + \text{H}_2\text{O}$	intermolecular

For aryl-alkyl ethers (e.g. anisole): aryl group must be the alkoxide ($\text{C}_6\text{H}_5\text{O}^- + \text{R-X}$); reverse fails (aryl halides inert to SN2).

Cleavage by HX

$$\boxed{\text{Reactivity: } \text{HI} > \text{HBr} \gg \text{HCl}}$$

Ether type	Excess HI/HBr products
Symmetrical (R-O-R)	2 R-X
Unsymmetrical alkyl-alkyl	two alkyl halides
Aryl-alkyl (e.g. $\text{C}_6\text{H}_5\text{-O-CH}_3$)	phenol + alkyl halide (aryl C-O does NOT break)

Anisole (-OCH₃ activating, ortho/para directing) undergoes nitration, halogenation, and Friedel–Crafts acylation on the ring.

Epoxides are the exception

Three-membered cyclic ethers (oxiranes) are highly reactive due to ring strain and open easily under acid or base; made from alkenes with mCPBA/RCO₃H. Normal ethers, by contrast, are inert and make great solvents.

Aldehydes and Ketones

Reactivity

$$\boxed{\text{Nucleophilic addition: } \text{HCHO} > \text{R-CHO} > \text{Ar-CHO} > \text{R-CO-R}'}$$

Aldehydes > ketones because they are less sterically hindered and less electron-rich (fewer +I alkyl groups on the δ⁺ carbonyl carbon).

Preparation

Method	Reagent	Product
1° alcohol oxidation	PCC	aldehyde (stops)
1° alcohol oxidation	$\text{K}_2\text{Cr}_2\text{O}_7/\text{H}^+$	carboxylic acid
2° alcohol oxidation	PCC or $\text{K}_2\text{Cr}_2\text{O}_7/\text{H}^+$	ketone
Ozonolysis of alkene	(1) $\text{O}_3$ (2) $\text{Zn}/\text{H}_2\text{O}$	aldehydes/ketones (cleaves C=C)
Alkyne hydration	$\text{H}_2\text{O},\,\text{H}_2\text{SO}_4,\,\text{HgSO}_4$	methyl ketone (via enol, keto-enol tautomerism)
Friedel–Crafts acylation	$\text{RCOCl}/\text{AlCl}_3$	aromatic ketone
Rosenmund reduction	$\text{H}_2/\text{Pd-BaSO}_4$	aldehyde from acyl chloride

Nucleophilic addition products

Nucleophile	Product
HCN	cyanohydrin (α-hydroxy nitrile)
$\text{NaHSO}_3$	bisulfite adduct (white solid; aldehydes & methyl ketones)
RMgX (then H₃O⁺)	alcohol (1°/2°/3° by Grignard pattern)
$\text{NH}_2\text{OH}$	oxime
$\text{NH}_2\text{-NH}_2$	hydrazone
$\text{NH}_2\text{-NH-C}_6\text{H}_5$	phenylhydrazone
$\text{NH}_2\text{-NH-CONH}_2$	semicarbazone

Condensation reactions

Aldol (needs α-H, dilute base): $2\,\text{CH}_3\text{CHO} \xrightarrow{\text{dil. NaOH}}$ 3-hydroxybutanal $\xrightarrow{-\text{H}_2\text{O}}$ but-2-enal (crotonaldehyde, α,β-unsaturated).
Cannizzaro (no α-H, conc. NaOH): $2\,\text{HCHO} \xrightarrow{\text{conc. NaOH}} \text{CH}_3\text{OH} + \text{HCOONa}$ (disproportionation).

Feature	Aldol	Cannizzaro
α-H	required	forbidden
Base	dilute	concentrated
Products	β-hydroxy carbonyl	alcohol + carboxylate

Reduction

Reagent	Result
$\text{LiAlH}_4$, $\text{NaBH}_4$, $\text{H}_2/\text{Ni}$	C=O → alcohol
Clemmensen ($\text{Zn-Hg}/\text{HCl}$)	C=O → CH₂
Wolff–Kishner ($\text{NH}_2\text{NH}_2$, KOH, heat)	C=O → CH₂

Qualitative tests

Test	Reagent	Positive for	Observation
Tollens'	$[\text{Ag(NH}_3)_2]^+/\text{OH}^-$	aldehydes	silver mirror
Fehling’s	Fehling’s A + B	aliphatic aldehydes	red $\text{Cu}_2\text{O}$ ppt
2,4-DNP	2,4-dinitrophenylhydrazine	aldehydes & ketones	orange/red ppt
Iodoform	$\text{I}_2/\text{NaOH}$	methyl ketones, CH₃CHO, CH₃CH(OH)-	yellow $\text{CHI}_3$ ppt

Iodoform structural rule

Positive iodoform needs a $\text{CH}_3\text{-CO-}$ or $\text{CH}_3\text{-CH(OH)-}$ group (the latter oxidises to a methyl ketone first). Acetaldehyde is the only aldehyde that gives it.

Haloform reaction

$$\text{R-CO-CH}_3 + 3\,\text{I}_2 + 4\,\text{NaOH} \rightarrow \text{R-COO}^-\text{Na}^+ + \text{CHI}_3\downarrow + 3\,\text{NaI} + 3\,\text{H}_2\text{O}$$

Carboxylic Acids

Acidity

$$\boxed{\text{Strong acids (HCl)} \gg \text{RCOOH} \gg \text{PhOH} > \text{H}_2\text{O} > \text{ROH}}$$$$\boxed{\text{p}K_a: \text{RCOOH }(\sim4\text{-}5) \ll \text{PhOH }(\sim10) < \text{H}_2\text{O }(\sim15.7) < \text{ROH }(\sim16)}$$

Carboxylate ion has two equivalent resonance structures → most stable conjugate base among these classes.

Substituent / inductive effects:

$$\boxed{\text{CCl}_3\text{COOH} > \text{CHCl}_2\text{COOH} > \text{CH}_2\text{ClCOOH} > \text{CH}_3\text{COOH}}$$

EWG (-F, -Cl, -Br, -NO₂, -CN) increase acidity; halogen strength F > Cl > Br > I.
EDG (-CH₃, -OCH₃, -NH₂) decrease acidity.
Inductive effect falls with distance: α > β > γ.

Physical property

Carboxylic acids form dimers (two H-bonds) in vapour/non-polar media → higher BP and apparent doubled molecular mass. Example: acetic acid (118 °C) > ethanol (78 °C).

Preparation

Method	Reagent	Note
Oxidation of 1° alcohol / aldehyde	$\text{K}_2\text{Cr}_2\text{O}_7/\text{H}^+$, $\text{KMnO}_4/\text{H}^+$, air	aldehydes oxidise even in air
Oxidation of alkylbenzene	$\text{KMnO}_4/\text{H}^+$, heat	any R → -COOH (needs benzylic H)
Nitrile hydrolysis	$\text{H}_3\text{O}^+$ or $\text{OH}^-/\text{H}_2\text{O}$	chain extension (+1 C)
Grignard + CO₂	(1) $\text{CO}_2$ (2) $\text{H}_3\text{O}^+$	chain extension (+1 C)
Ester hydrolysis (saponification)	NaOH/H₂O, then H⁺	gives acid + alcohol

Derivative formation

Derivative	Reagent
Acid chloride	$\text{SOCl}_2$ (gaseous byproducts), $\text{PCl}_3$, $\text{PCl}_5$
Ester	$\text{R}'\text{OH} + $ conc. $\text{H}_2\text{SO}_4$ (Fischer, reversible)
Amide	via acid chloride + NH₃ (or heat ammonium salt)
Anhydride	$\text{P}_2\text{O}_5$, heat

$$\boxed{\text{Derivative reactivity (nucleophilic acyl substitution): RCOCl} > (\text{RCO})_2\text{O} > \text{RCOOR}' > \text{RCONH}_2}$$

Order follows leaving-group ability: $\text{Cl}^- > \text{RCOO}^- > \text{RO}^- > \text{NH}_2^-$.

Other key reactions

Reduction: $\text{R-COOH} \xrightarrow{\text{LiAlH}_4,\,\text{then H}_3\text{O}^+} \text{R-CH}_2\text{OH}$ ($\text{NaBH}_4$ too weak).
Decarboxylation (sodalime, NaOH + CaO, heat): $\text{R-COOH} \rightarrow \text{R-H} + \text{Na}_2\text{CO}_3$ (−1 C).
Kolbe electrolysis: $2\,\text{R-COO}^-\text{Na}^+ \xrightarrow{\text{electrolysis}} \text{R-R} + 2\,\text{CO}_2$.
Hell–Volhard–Zelinsky: $\text{R-CH}_2\text{-COOH} \xrightarrow{\text{X}_2/\text{P}} \text{R-CHX-COOH}$ (α-halogenation).
NaHCO₃ test: $\text{R-COOH} + \text{NaHCO}_3 \rightarrow \text{R-COO}^-\text{Na}^+ + \text{H}_2\text{O} + \text{CO}_2\uparrow$ (distinguishes from phenol).

Special acids

Formic acid (HCOOH): has an aldehyde-like H on the carbonyl carbon → only carboxylic acid that reduces Tollens’ and Fehling’s.
Oxalic acid ((COOH)₂): reduces $\text{KMnO}_4$, used to standardise it in titrations: $$5\,(\text{COOH})_2 + 2\,\text{KMnO}_4 + 3\,\text{H}_2\text{SO}_4 \rightarrow 10\,\text{CO}_2 + 2\,\text{MnSO}_4 + \text{K}_2\text{SO}_4 + 8\,\text{H}_2\text{O}$$

Acidity hierarchy and the NaHCO₃ litmus

The single most-tested fact: RCOOH > H₂CO₃ > phenol, so only carboxylic acids fizz with NaHCO₃. Phenol reacts with NaOH but not NaHCO₃; alcohols react with neither.

Cross-Chapter Quick Reference

Distinguish	Test	Result
Phenol vs alcohol	$\text{FeCl}_3$	phenol violet; alcohol none
Phenol vs RCOOH	$\text{NaHCO}_3$	RCOOH fizzes; phenol none
Aldehyde vs ketone	Tollens’ / Fehling’s	aldehyde positive
Methyl ketone	iodoform	yellow $\text{CHI}_3$
Any C=O	2,4-DNP	orange ppt
1°/2°/3° alcohol	Lucas	3° instant, 2° ~5 min, 1° none

Reagent cheat-sheet

Want	Reagent
Stop 1° alcohol at aldehyde	PCC (anhydrous, CH₂Cl₂)
1° alcohol → carboxylic acid	$\text{K}_2\text{Cr}_2\text{O}_7/\text{H}_2\text{SO}_4$
Reduce ester/acid → 1° alcohol	$\text{LiAlH}_4$ (not $\text{NaBH}_4$)
Alcohol → alkene	conc. $\text{H}_2\text{SO}_4$, 170 °C
Alcohol → symmetrical ether	conc. $\text{H}_2\text{SO}_4$, 140 °C
Make acid chloride	$\text{SOCl}_2$
C=O → CH₂	Clemmensen or Wolff–Kishner

Functional Groups at a Glance

Alcohols

Classification and reactivity

Preparation

Key reactions

Lucas test (HCl + ZnCl₂)

Phenols

Acidity

Preparation

Electrophilic substitution (ortho/para, often no catalyst)

Name reactions

Tests and contrasts

Ethers

Physical properties

Preparation

Cleavage by HX

Aldehydes and Ketones

Reactivity

Preparation

Nucleophilic addition products

Condensation reactions

Reduction

Qualitative tests

Haloform reaction

Carboxylic Acids

Acidity

Physical property

Preparation

Derivative formation

Other key reactions

Special acids

Cross-Chapter Quick Reference

Reagent cheat-sheet

Connection to Other Topics

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