Katalis Homogen

Katalis

Jenis katalis

Katalis homogen adalah senyawa yang ada dalam fase yang sama (gas atau cair) sebagai reaktan,

sedangkan katalis heterogen

Katalisis asam, katalis organologam, dan katalisis enzima

Keuntungan dari katalis homogen adalah bahwa katalis lebih cepat bercampur ke dalam campuran reaksi, yang memungkinkan

Organometallic

According to RSC

According to ACS

Noble-Prize Winners in Works Related to OM

Grignard & Saba

Trans Eect

In inorganic chemistry, the trans eect is the labiliza

ELECTRON COUNTING

Basis of Electron Coun

Importance of Electron Coun

Coun

Method 1: The ionic (charged) model

Pada metode ini melibatkan ligan sebagai pendonor pasangan electron ke logam. Untuk menentukan jumlah total electron, kita harus menghitung juga muatan se

Method 2: The covalent (neutral) model

Pada metode ini kita akan menggunakan jumlah electron yang akan didonasikan oleh ligand tetapi dalam keadaan netral. Pada ligan anorganik sederhana, jumlah electron yang didonasikan sama dengan muatan nega

Ligan dengan donasi elektronnya

TRANSITION METALS ORGANOMETALLICS

A transi:on metal is one which forms one or more stable ions which have incompletely

lled d orbitals.

Transition vs Main Elements The physical and chemical properties of transition metals differ from main group metals (s-block) by the following: are hard and have high densities. have high melting and boiling points. form compounds which are often paramagnetic. show variable oxidation states. form coloured ions and compounds. form compounds with profound catalytic activity. form stable complexes.

Transi:on Metals Overview

Early Transi:on Metals Groups 3, 4

Strongly electrophilic (Strongly bounds to high electronega

Early Transi:on Metals Groups 3,4

Typical catalysis in Polymerization

"Middle" Transi:on Metals Groups 5-7

Many accessible oxida

"Middle" Transi:on Metals Groups 5-7 Typical catalysis: Alkene and alkyne metathesis

Late Transi

Late Transi

Transi

1st row: o`en unpaired electrons (High spin state). dierent spin states (HS/LS) accessible highest oxida

Nomenclature

The mode of aRachment of the donor ligand is described by deno

Metal Carbonyls (Bonding)

Evidence of Back-bonding

Note that an empty orbital in the ligand (LUMO) is used in the bonding (an an

Metal Phosphines

Ter

Bonding in Metal Phosphines

Electronic Eects of Phosphines

Controlling The Space Around The Metal

Correla:on of Cone Angles & Reac:on

Mono-dentate Phosphines

We can increase the bulkness around the metal by replacing the phosphine ligand without aec

Tolman plot of Electronic Parameter and Cone Angle

Hydrido Complexes

METAL AMINE

Metal Alkenes (Bonding)

Ligand Assosia

Dissocia

Commonly observed mechanis

An Example of an Oxida

Oxida

Commonly used sources of Pd0 include:

Tris(dibenzylideneacetone)dipalladium (0) Pd2(dba)3

Tetrakis(triphenylphosphine)palladium (0)

Pd(PPh3)4

Also, Pd(II) is very readily reduced to Pd(0):

Thus, it is o`en more convenient to use Pd(II) complexes, which are more air-stable than commercial Pd(0) complexes.

2) Reduc

Complex Rate Constant (s-1) T(oC)

PdCH3Ph3P

Ph3P CH3

PdCH3MePh2P

MePh2P CH3

PdCH3P

P CH3

PhPh

PhPh

1.04 x 10-3 60

60

80

9.62 x 10-5

4.78 x 10-7

Relative rates of reductive elimination

Most crowded is the fastest reaction

PdCH3L

L CH3+ solv

-L

PdCH3L

solv CH3

RELPd(solv) + CH3 CH3

Transmetalla

Now we will put the three reac

SUZUKI-MIYAURA CROSS COUPLING REACTION

Bagaimana Mekanismenya??

MECHANISM OF SUZUKI-MIYAURA CROSS COUPLING REACTION

Selected examples of the Suzuki-Miyaura coupling in organic synthesis

When a reac

Negishi Cross-Coupling Reac

I OR + ZnCl ORTHF, 60o C

[Pd(PPh3)2Cl2]

L = (PPh3)2

Predict the main products, include the mechanism

To understand the Heck Reac

The inser

The -hydride Elimina

Heck Reac

I +Pd-Cat

n-Bu3N, DMF

Br +THF, 60o C

Pd-Cat

O

O

O

O

The Heck reac