C-F形成的综述—美国化学协会Chemical review

C-F Bond Activation in Organic Synthesis

Hideki Amii*,†and Kenji Uneyama*,‡

Department of Chemistry,Graduate School of Science,Kobe University,Kobe657-8501,Japan,and Department of Applied Chemistry,Faculty of

Engineering,Okayama Univeristy,Okayama700-8530,Japan

Received June27,2008 Contents

1.Introduction2119

2.C-F Bond Activation in Aromatic Fluorides2120

2.1.Oxidative Addition of C-F Bond to

Low-Valent Metals

2120

2.1.1.Transition Metal-Mediated Activation of

sp2-C-F Bonds:Stoichiometric Reactions

2121

2.1.2.Transition Metal-Mediated Activation of

sp2-C-F Bonds:Catalytic Transformations

2124

2.1.

3.Ni-Catalyzed Cross-Coupling Reactions of

Aromatic Fluorides

2125

2.1.4.Pd-Catalyzed Cross-Coupling Reactions of

Aromatic Fluorides

2127

2.1.5.Other Transition Metal Catalyzed

Cross-Coupling Reactions

2129

2.2.C-F Bond Activation Initiated by Electron

Transfer to Fluoroaromatics

2130

2.2.1.Catalytic Hydrogenolysis of Aromatic C-F

Bonds

2130

2.2.2.Reductive Transformations of Fluoroarenes2132

2.3.Nucleophilic Substitution in Aromatic Fluorides2136

2.3.1.Nucleophilic Substitution in

Monofluoroaromatics

2136

2.3.2.Nucleophilic Substitution in

Hexafluorobenzene

2141

2.3.3.Nucleophilic Substitution in

Pentafluoropyridine

2143

2.4.Defluorination via Benzynes2145

3.C-F Bond Activation in Alkenyl Fluorides2148

3.1.General Aspect of Nucleophilic Substitution in

gem-Difluoroalkenes

2148

3.2.Structure and Reactivity of

gem-Difluoroalkenes

2150

3.3.Intramolecular Nucleophilic Substitution in

gem-Difluoroalkenes

2151

3.4.High Reactivity and Toxicity of Polyfluorinated

Fluoroalkenes

2152

3.5.Defluorinative Modification of

Octafluorocyclopentene

2152

4.C-F Bond Activation in Aliphatic Fluorides2153

4.1.C-F Bond Activation of Trifluoromethyl Group

Attached toπ-Electron System

2153

4.1.1.S N2′Type Reactions in

Trifluoromethylalkenes

2153

4.1.2.Fluoride-Ion Catalyzed Desilylative

Defluorination 2156

4.1.3.Electroreductive C-F Bond Activation2158

4.2.Low-Valent Metal-Promoted Reductive C-F

Bond Cleavage

2160

4.2.1.Low-Valent Metal-Promoted Reductive

Dehalodefluorination

2162

4.2.2.Low-Valent Metal-Promoted Reductive

Defluorination from Trifluoromethyl Group

Attached toπ-Electron System

2163

4.3.Lewis Acid-and Cation-Promoted C-F Bond

Activation

2168

4.4.Ate Complex-Catalyzed Cross-Coupling2173

4.5.E2-type Dehydrofluorination2174

4.5.1.Dehydrofluorination of Trifluoromethyl

Compounds

2175

4.5.2.Dehydrofluorination Leading to

Quinodimethane Intermediates

2175

4.5.3.Brook Rearrangement2176

5.Concluding Remarks2177

6.Acknowledgments2177

7.References2177

1.Introduction

Fluorine has received great attention in allfields of science.

“Small atom with a big ego”was the title of the Symposium

at the ACS meeting in San Francisco in2000,where a

number of the current scientific and industrial aspects of

fluorine chemistry made possible by the small size and high

electronegativity of the atom were discussed.This small atom

has provided mankind with significant benefits in special

products such as poly(tetrafluroethylene)(PTFE),freon,

fluoro-liquid crystals,opticalfiber,pharmaceutical and

agrochemical compounds,and so on,all of which have their

own unique properties that are otherwise difficult to obtain.1

For instance,at present,up to30%of agrochemicals and

10%of pharmaceuticals currently used containfluorine

atoms.Therefore,organicfluorine compounds have received

a great deal of interest and attention from the scientists

involved in diversefields of science and technology.

Now,not only C-F bond formation but also selective

C-F bond activation have become current subjects of active

investigation from the viewpoint of effective synthesis of

fluoroorganic compounds.The former is highlighted by

designing a sophisticatedfluorinating reagent for regio-and

stereocontrolledfluorination and developing versatile mul-

tifunctional and easily prepared building blocks.C-F bond

formation has been treated extensively in several reviews2

and books.3The latter is a subject that has been less explored

but would be promising for selective defluorination of

aliphaticfluorides,cross-coupling with arylfluorides,and

*To whom correspondence should be addressed.Phone:81-78-803-5799.

Fax:81-78-803-5799.E-mail:amii@kobe-u.ac.jp and uneyamak@cc.okayama-

u.ac.jp.

†Kobe University.

‡Okayama University.

Chem.Rev.2009,109,2119–21832119

10.1021/cr800388c CCC:$71.50 2009American Chemical Society

Published on Web03/30/2009