User:Benjah-bmm27/degree/3/GCLJ2

=Synthetic uses of transition metals, GCLJ=

Textbooks

 * Clayden, Chapter 48 (Organometallic chemistry), pp. 1311–1343

Introduction

 * Organopalladium chemistry
 * R-Pd-X species are not [R−][+PdX]
 * no carbanionic character
 * not basic or nucleophilic
 * react with nucleophiles (pi donors, R′-M)
 * Pd(II) slightly electrophilic
 * Transmetallation
 * Tris(dibenzylideneacetone)dipalladium(0), Pd2(dba)3

Pd-catalyzed coupling reactions

 * Palladium-catalyzed coupling reactions

Stille

 * Stille coupling

Suzuki

 * Suzuki coupling
 * use catecholborane to form vinylborane precursor
 * use Pd(PPh3)2Cl2 to catalyse addition of RX (organohalide, e.g. PhBr)

Negishi

 * Negishi coupling

Kumada

 * Kumada coupling

Sonogashira

 * Sonogashira coupling

Use of Sonogashira coupling in enediyne synthesis

 * Synthesis of calicheamicin
 * calicheamicin is an enediyne antibiotic and anti-tumour drug: the enediyne "warhead" or "business end" works by doing a Bergman cyclization

Hartwig-Buchwald coupling

 * "Amination", R-X → R-NH-R′
 * RX + R′NH2 → RNHR′ + HX
 * Catalysed by 0PdL2
 * [R′H2N+PdL2R][X−] deprotonated

Heck reaction

 * Heck reaction
 * Named after Richard Heck who developed the reaction in the 1970s

Mechanism

 * ChemTube3D animated Jmol mechanism
 * Surawatanawonga, Fan, Hall (2008) Density functional study of the complete pathway for the Heck reaction with palladium diphosphines
 * Surawatanawong, Hall (2008) Theoretical Study of Alternative Pathways for the Heck Reaction through Dipalladium and “Ligand-Free” Palladium Intermediates

Other interactions of alkenes with Pd(II)

 * Allylic rearrangements

Cyclopropanation using electrophilic carbene complexes

 * Cyclopropanation using electrophilic carbene complexes
 * Carbene complexes are often called carbenoids
 * Cyclopropanes are found in nature as pyrethrins, and are produced synthetically as pyrethroid insecticides
 * Use ethyl diazoacetate as a source of :CEt2 (or more generally use R2CN2 as a source of :CR2)
 * Use an alkene as a source of R2C•—•CR2
 * R2C: + R2C•—•CR2 → cyclo-(R2C)3, i.e. a cyclopropane
 * Cu or Rh catalyst

Cilastatin synthesis

 * Example of a Cu-catalysed asymmetric cyclopropanation: synthesis of cilastatin

Ring-closing metathesis

 * Ring-closing metathesis
 * catalysed by Grubbs' first generation catalyst, Cl2(Cy3P)Ru=CHPh