1. Oxidative Addition, Reductive Elimination
Oxidative addition, reductive elimination Heck reaction, Suzuki coupling
Concerted addition
Often with H2, alkanes, R3SiH, O2
Stepwise
Often with HX, R3SnX, alkyl acyl and allyl halides and an electron-rich metal (IrI, RhI, Pd(0))
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Oxidative Addition, Reductive Elimination

2. Oxidative addition, reductive elimination
Sometimes radical mechanism:
Test:
Formation R-R
CIDNP
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Oxidative Addition, Reductive Elimination

3. Oxidative addition, reductive elimination
Promote oxidative addition:
Strongly basic metal fragment
Concerted: weak, apolar s bond
Stepwise: polar bond, good leaving group
C-H: arene > alkane
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Oxidative Addition, Reductive Elimination

4. Oxidative Addition, Reductive Elimination
The Heck reaction
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Oxidative Addition, Reductive Elimination

5. Oxidative Addition, Reductive Elimination
The Heck reaction
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Oxidative Addition, Reductive Elimination

6. Suzuki and Stille coupling
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Oxidative Addition, Reductive Elimination

7. Suzuki and Stille coupling
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Oxidative Addition, Reductive Elimination

8. Reductive elimination
Usually easy for:
H + alkyl / aryl / acyl
alkyl + acyl
SiR3 + alkyl etc
Often slow for:
alkoxide + alkyl
halide + alkyl
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Oxidative Addition, Reductive Elimination

9. Oxidative Addition, Reductive Elimination
Hydrogenation (1)
Variation:
direct s-bond metathesis
of M-R with H2
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Oxidative Addition, Reductive Elimination

10. Oxidative Addition, Reductive Elimination
Hydrogenation (2)
(what is wrong with this cycle?)
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Oxidative Addition, Reductive Elimination