Haloalkanes & Haloarenes — Formulas, Reactions & Conditions — Notes

Rate Laws

$\text{SN1: Rate} = k[\text{RX}]$ $\text{SN2: Rate} = k[\text{RX}][\text{Nu}^-]$ $\text{E1: Rate} = k[\text{RX}]$ $\text{E2: Rate} = k[\text{RX}][\text{Base}]$

Bond Energy Values

$\text{C-F}: 485 \text{ kJ/mol} \quad \text{C-Cl}: 339 \text{ kJ/mol} \quad \text{C-Br}: 285 \text{ kJ/mol} \quad \text{C-I}: 213 \text{ kJ/mol}$

Bond Length Values

$\text{C-F}: 135 \text{ pm} \quad \text{C-Cl}: 177 \text{ pm} \quad \text{C-Br}: 193 \text{ pm} \quad \text{C-I}: 214 \text{ pm}$

Key Named Reactions

Named Reaction	Equation	Reagent	Solvent	Driving Force
Finkelstein	RCl + NaI → RI + NaCl↓	NaI	Acetone	NaCl precipitates
Swarts	RBr + AgF → RF + AgBr↓	AgF	—	AgBr precipitates
Dow Process	$C_{6}H_{5}Cl$ + NaOH → $C_{6}H_{5}OH$ + NaCl	NaOH	—	623 K, 300 atm

Reaction Conditions Table

Reaction Type	Substrate	Reagent	Solvent	Temperature	Product
SN1	3° R-X	$H_{2}O$ or ROH	Polar protic	Room temp	ROH (racemic)
SN2	1° R-X	NaOH, NaCN, NaI	DMSO, DMF, acetone	Room temp	R-OH, R-CN, R-I (inverted)
E2 (Saytzeff)	2° or 3° R-X	KOH/EtOH	Ethanol	High (60-80°C)	Alkene (more substituted)
E2 (Hofmann)	2° R-X	t-BuOK/t-BuOH	t-Butanol	70°C	Alkene (less substituted)
E1	3° R-X	$H_{2}O$	Protic	High temp	Alkene (Saytzeff)
Grignard prep	R-X	Mg	Dry ether	25°C	R-MgX
NAS (Dow)	Ar-Cl	NaOH	—	623 K, 300 atm	Ar-OH

Grignard Carbonyl Reactions

$\text{RMgX} + \text{HCHO} \xrightarrow{\text{dry ether}} \text{RCH}_2\text{OMgX} \xrightarrow{\text{H}_3\text{O}^+} \text{RCH}_2\text{OH (1° alcohol, +1 C)}$ $\text{RMgX} + \text{R'CHO} \xrightarrow{\text{dry ether}} \text{RR'CHOMgX} \xrightarrow{\text{H}_3\text{O}^+} \text{RR'CHOH (2° alcohol)}$ $\text{RMgX} + \text{R'}_2\text{CO} \xrightarrow{\text{dry ether}} \text{RR'}_2\text{COMgX} \xrightarrow{\text{H}_3\text{O}^+} \text{RR'}_2\text{COH (3° alcohol)}$ $\text{RMgX} + \text{CO}_2 \xrightarrow{\text{dry ether}} \text{RCOOMgX} \xrightarrow{\text{H}_3\text{O}^+} \text{RCOOH (carboxylic acid, +1 C)}$

Phosgene Formation

$2\text{CHCl}_3 + \text{O}_2 \xrightarrow{\text{light}} 2\text{COCl}_2 + 2\text{HCl}$

CFC Ozone Depletion Mechanism

$\text{CF}_2\text{Cl}_2 \xrightarrow{\text{UV}} \bullet\text{CF}_2\text{Cl} + \text{Cl}\bullet$ $\text{Cl}\bullet + \text{O}_3 \rightarrow \text{ClO}\bullet + \text{O}_2$ $\text{ClO}\bullet + \text{O}\bullet \rightarrow \text{Cl}\bullet + \text{O}_2$ $\text{Net: } \text{O}_3 + \text{O}\bullet \rightarrow 2\text{O}_2 \quad \text{(Cl is regenerated — catalytic)}$