p. 445 Chapter 12: Organohalides 12.5 – : Substitution and Elimination Reactions 12.4 : The Grignard Reagent : Preparation of Alkyl Halides

Fig. 12-2, p. 455 The Walden Inversion Cycle (1896) (+)-Maleic Acid [  ] D = +2.3 (-)-Maleic Acid [  ] D = -2.3 (+)-chlorosuccinic acid (-)-chlorosuccinic acid

Fig. 12-5, p. 459

Characteristics of the S N 2 reaction 1.Rate equation

Characteristics of the S N 2 reaction 1.Rate equation 2.Molecular factors effecting S N 2 reaction rate

Fig. 12-6, p. 460 The Effect of Reactant and Transition Structure Energies on Reaction Rate

p. 461 Effect of ELECTROPHILIC CARBON on S N 2 rate

Fig. 12-7, p. 461 Effect of ELECTROPHILIC CARBON on S N 2 rate

The sterics around the electrophilic carbon alters the S N 2 rate by changing… A.The ground state energy of the starting materials. B.The energy of the transition state.

Effect of ELECTROPHILIC CARBON on S N 2 rate

p. 463 Effect of LEAVING GROUP on S N 2 rate

The leaving group alters the S N 2 rate by changing… A.The ground state energy of the starting materials. B.The energy of the transition state.

Effect of LEAVING GROUP on S N 2 rate

Table 12-2, p. 462 Effect of NUCLEOPHILE on S N 2 rate

The nucleophile alters the S N 2 rate by changing… A.The ground state energy of the starting materials. B.The energy of the transition state.

Effect of NUCLEOPHILE on S N 2 rate

p. 465 Effect of Solvent on S N 2 rate

Poorly solvated anion (increased nucleophilicity) Well solvated anion (reduced nucleophilicity)

The solvent alters the S N 2 rate by changing… A.The ground state energy of the starting materials. B.The energy of the transition state.

Solvent effects on S N 2 rate

Fig. 12-8, p. 466

Characteristics of the S N 1 reaction 1.Rate equation

Characteristics of the S N 1 reaction 1.Rate equation 2.Molecular factors effecting S N 1 reaction rate

p. 467 Effect of electrophilic carbon on S N 1 rate

Fig , p. 469 Stereochemical effects of the S N 1 mechanism

Fig , p. 470 Stereochemical effects of the S N 1 mechanism

p. 472 Effect of electrophilic carbon on S N 1 rate: Carbocation Stability

Fig , p. 471 Effect of electrophilic carbon on S N 1 rate: Resonance in Carbocations

p. 472 Bond Disassociation Energies and Carbocation Stability < 

p. 472 Effect of LEAVING GROUP on S N 2 rate Effect of LEAVING GROUP on S N 1 rate

Fig , p. 474 Effect of Solvent on S N 1 rate

p. 474 Effect of Solvent on S N 1 rate

S N 2 vs. S N 1

What is the mechanism for the reaction below? A.S N 1 B.S N 2

What is the mechanism for the reaction below? A.S N 1 B.S N 2

What is the mechanism for the reaction below? A.S N 1 B.S N 2

What is the mechanism for the reaction below? A.S N 1 B.S N 2

Elimination Reactions 1.Intro: Eliminations vs. Substitutions The E2 Mechanism 1.Rate 2.Molecular factors effecting the E2 mechanism  Stereochemistry  Zaitzev’s Rule  Barton’s Experiments

Fig , p. 482 Stereochemistry of the E2 mechanism

Elimination Reactions : The E1 Mechanism 1.Rate 2.E1 and S N 1 3.Molecular factors effecting the E2 mechanism  Stereochemistry  Zaitzev’s Rule

Summing it all up : S N 1, S N 2, E1 and E2 1. Primary Alkyl Halides 2. Secondary Alkyl Halide 3. Tertiary Alkyl Halides

Table 12-1, p. 446 Properties of Alkyl Halides

p. 447 Properties of Alkyl Halides

p. 453 The Grignard Reagent

p. 227 Synthesis of alkyl halides : review 1.Addition of HX to an alkene (section 7.6) a.Obeys Markovnikov’s Rule (section 7.7)

p. 239 Synthesis of alkyl halides : review 1.Addition of HX to an alkene (section 7.6) a.Obeys Markovnikov’s Rule (section 7.7) b.Carbocations that can rearrange, will rearrange (section 7.10)

p. 255 Synthesis of alkyl halides : review 2. Addition of X 2 to an alkene (section 8.2) Anti addition

p. 255 Synthesis of alkyl halides : review 3. Radical Halogenation (section 6.3) Statistical

Synthesis of alkyl halides : New 1.From alkynes Allylic bromination with N-Bromo Succinimide 2.From Alcohols a.Using strong acid b.Via Tosylates c.Using SOCl 2 and PBr 3

Fig. 12-1, p. 449 The Allyl Radical

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