Inorganic

Catalytic Deuteration

• Complex: (η5-C₅H₅)2TaH₃

• Use: Used to exchange hydrogen (H) for deuterium (D) in substrates using D₂ gas.

• Key Step: Oxidative addition of D₂, followed by reductive elimination with the substrate — leaves deuterium in place of hydrogen.

Hydroformylation

Rxn: Alkene+H₂​+CO→Aldehyde with one more C

• Catalysts:

  • HCo(CO)₄ (classic)

  • HCo(CO)₃(PBu₃) (ligand-modified cobalt)

  • HRh(CO)₂(PPh₃)₂ (more selective rhodium catalyst)

• Steps:

  1. Alkene coordination

  2. Insertion into M–H bond

  3. CO insertion

  4. Reductive elimination to form the aldehydeMonsanto Acetic Acid Synthesis

Monsanto Acetic Acid Synthesis

Reaction: Methanol+CO→Acetic Acid

• Catalyst: [I₂Rh(CO)₂]⁻

• Mechanism:

  1. Methanol reacts to form methyl iodide

  2. Oxidative addition of Me–I to Rh(I)

  3. CO insertion

  4. Reductive elimination gives acetyl iodide

  5. Hydrolysis → acetic acid

Hydrogenation (Wilkinson’s Catalyst)

Catalyst: ClRh(PPh₃)₃

• Reaction:

  Alkene+H₂→Alkane

• Steps:

  1. Oxidative addition of H₂ → Rh(III)–H₂

  2. Alkene coordination

  3. Insertion of alkene into Rh–H bond

  4. Reductive elimination → alkane

• Asymmetric version: Uses chiral phosphine ligands to hydrogenate prochiral alkenes selectively (e.g., BINAP)

Transmetallation Reactions

• : Exchange of an organic group (R) between two metals.

• Example Context: Seen in cross-coupling reactions like Suzuki or Stille.

  • Ex: R–SnBu₃ + Pd–X → R–Pd–X+SnBu₃X

• Why It Matters: Key step for installing organic groups onto metals for further coupling or elimination.