Selective Hydrogenation of Functionalized Hydrocarbons
Authors: Blaser Hans‐Ulrich , Schnyder Anita , Steiner Heinz , Rössler Felix , Baumeister Peter 
Published: March 2008

Abstract
The sections in this article are

Introduction

Significance of Catalytic Methods in Organic Synthesis

Guidelines for the Selection of a Catalytic Hydrogenation System

Introduction

General Approaches to Tuning Catalytic Processes

A
Selectivity in Catalytic Hydrogenation: a Challenge for Organic Chemists

B
Concepts and Tools Useful for Catalytic Hydrogenation

General Strategy and Experiment Planning

Catalyst Selection

A
Metal Selection

B
Catalyst Support

C
Catalyst Particle Size and Morphology

D
Porosity of the Support and Location of the Metal

E
Metal Dispersion and Metal Crystallite Size

F
Other Factors

Selection of the Reaction Medium

A
Solvent

B
Acids and Bases

C
Catalyst Modifiers

Reaction Conditions

A
Temperature

B
Hydrogen Pressure

C
Substrate Concentration

D
Catalyst Loading and Substrate to Catalyst Ratio

E
Degree of Conversion

Chemoselectivity in Catalytic Hydrogenation

Selective Hydrogenation of Functionalized Aromatic Nitro Compounds

Introduction

Mechanism of Nitroarene Reductions

Practical Aspects

A
Catalysts

B
Reaction Medium and Conditions

C
Safety and Health Aspects

a
Hazards Related to Hydrogen

b
Hazards Related to the Catalyst

c
Hazards Due to the Hydrogenation Reaction

d
Hazards Due to the High Decomposition Energy of Aromatic Nitro Compounds and some Intermediates

e
Toxicity

D
Hydrogenation Equipment

Selective Hydrogenation of Halogenated Nitroarenes

A
Introduction

B
Catalysts

a
Modified Catalysts

b
In Situ
Modification

New Catalyst Systems for the Hydrogenation of a Nitro Group in the Presence of Reducible Functional Groups

A
Lead‐Modified Platinum Catalysts: the “Lindlar Approach”

B
H
3
PO
2
‐Modified
Pt
Catalysts in the Presence of Vanadium Promoters

Hydroxylamine Accumulation

Selective Semihydrogenation of Alkynes

Introduction

Chemical and Physical Background for Selectivity in Alkyne Hydrogenation

Tools to Achieve Selectivity for Alkene Formation

A
Metal Selection

B
Chemical Composition of the Support

C
Metal Location

D
Metal Dispersion and Crystallite Size

E
Catalyst Modifiers

F
Solvent

G
Temperature

H
Hydrogen Pressure

I
Substrate Concentration

J
Catalyst/Substrate Ratio

K
Agitation

L
Degree of Conversion

Selective Catalytic Debenzylation

Introduction

Catalysts Used for Selective Debenzylation

Influence of Reaction Conditions

A
Hydrogen Source and Pressure

B
Solvent, Modifiers and Promoters

Selective Removal of Benzyl Groups

A
Selective Removal of
O
‐Benzyl Groups in the Presence of other
O
‐Benzyl Groups

B
Selective Removal of
O
‐Benzyl Groups in the Presence of
N
‐Benzyl Groups

C
Selective Removal of
O
‐Benzyl Groups in the Presence of other Reducible Functions

D
Selective Removal of
N
‐Benzyl Groups in the Presence of other
N
‐Benzyl Groups

E
Selective Removal of
N
‐Benzyl Groups in the Presence of other Reducible Functions

F
New Protecting Groups

Mechanism of Debenzylation and Mode of Action of Modifiers

Stereoselective Reactions

Diastereoselective Hydrogenation

Enantioselective Hydrogenation

Chemoselective Hydrogenation of Nitriles

Primary Amine Formation

Chemoselective Hydrogenation of Unsaturated Nitriles