Mechanistic Studies of the Rhodium NHC Catalyzed Hydrodefluorination of Polyfluorotoluenes

被引：31

作者：

Schwartsburd, Leonid ^{[1
]}

Mahon, Mary F. ^{[1
]}

Poulten, Rebecca C. ^{[1
]}

Warren, Mark R. ^{[2
]}

Whittlesey, Michael K. ^{[1
]}

机构：

[1] Univ Bath, Dept Chem, Bath BA2 7AY, Avon, England

[2] Diamond Lightsource Ltd, Stn 119, Didcot OX11 ODE, Oxon, England

来源：

ORGANOMETALLICS | 2014年 / 33卷 / 21期

基金：

英国工程与自然科学研究理事会;

关键词：

C-F ACTIVATION; H BOND ACTIVATION; CARBON-FLUORINE BONDS; ROOM-TEMPERATURE; CARBENE COMPLEXES; FACILE ACCESS; FLUOROARENES; TRIFLUOROTOLUENES; FLUOROAROMATICS; PERFLUOROARENES;

D O I：

10.1021/om500827d

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

The six-membered-ring NHC complexes Rh(6-NHC)(PPh3)(2)H (6-NHC = 6-Pr-i (1), 6-Et (2), 6-Me (3)) have been employed in the catalytic hydrodefluorination (HDF) of C6F5CF3 and 2-C6F4HCF3. Stoichiometric studies showed that 1 reacted with C6F5CF3 at room temperature to afford cis- and trans-phosphine isomers of Rh(6-Pr-i)(PPh3)(2)F (4), which re-form 1 upon heating with Et3SiH. Although up to three consecutive HDF steps prove possible with C6F5CF3, the ultimate effectiveness of the catalysts is limited by their propensity to undergo CH activation of partially fluorinated toluenes to give, for example, Rh(6-Pr-i)(PPh3)(2)(C6F4CF3) (7), which was isolated and structurally characterized.

引用

页码：6165 / 6170

页数：6

共 75 条

[1] Catalytic Hydrodefluorination of Fluoromethanes at Room Temperature by Silylium-ion-like Surface Species [J].

Ahrens, Mike ;

Scholz, Gudrun ;

Braun, Thomas ;

Kemnitz, Erhard .

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 2013, 52 (20) :5328-5332

[2] HOMOGENEOUS METAL-CATALYZED HYDROGENOLYSIS OF C-F BONDS [J].

AIZENBERG, M ;

MILSTEIN, D .

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1995, 117 (33) :8674-8675

[3] CATALYTIC ACTIVATION OF CARBON-FLUORINE BONDS BY A SOLUBLE TRANSITION-METAL COMPLEX [J].

AIZENBERG, M ;

MILSTEIN, D .

SCIENCE, 1994, 265 (5170) :359-361

[4] Hydrodefluorinations of trifluorotoluenes by LiAlH4 and TiCl4 [J].

Akiyama, Takahiko ;

Atobe, Kohei ;

Shibata, Michiko ;

Mori, Keiji .

JOURNAL OF FLUORINE CHEMISTRY, 2013, 152 :81-83

[5] On the Catalytic Hydrodefluorination of Fluoroaromatics Using Nickel Complexes: The True Role of the Phosphine [J].

Arevalo, Alma ;

Tlahuext-Aca, Adrian ;

Flores-Alamo, Marcos ;

Garcia, Juventino J. .

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2014, 136 (12) :4634-4639

[6] CLEAVAGE OF BOTH ALKYL C-H BONDS AND ARYL C-F BONDS AND CONCOMITANT C-C BOND FORMATION IN A PENTAMETHYLCYCLOPENTADIENYLRHODIUM PHOSPHINE COMPLEX - X-RAY STRUCTURE OF [(ETA(5)-C(5)ME(3)[CH2C(6)F(4)P(C6F5)CH2](2)-1,3)RHCL]+BF4- [J].

ATHERTON, MJ ;

FAWCETT, J ;

HOLLOWAY, JH ;

HOPE, EG ;

KARACAR, A ;

RUSSELL, DR ;

SAUNDERS, GC .

JOURNAL OF THE CHEMICAL SOCIETY-CHEMICAL COMMUNICATIONS, 1995, (02) :191-192

[7] Activation of C-F and C-H bonds by polyalkylcyclopentadienylrhodium complexes:: crystal structure of [(η5-C5Me4Et)RhCl{(C6F5)2PCH2CH2P(C6F5)2}]+.BF4- [J].

Atherton, MJ ;

Fawcett, J ;

Holloway, JH ;

Hope, EG ;

Martin, SM ;

Russell, DR ;

Saunders, GC .

JOURNAL OF ORGANOMETALLIC CHEMISTRY, 1998, 555 (01) :67-79

[8] Photochemical intermolecular C-H and C-F insertion of rhodium into pentafluoroanisole to generate a metallacycle; Conversion to a cyclic carbene complex [J].

Ballhorn, M ;

Partridge, MG ;

Perutz, RN ;

Whittlesey, MK .

CHEMICAL COMMUNICATIONS, 1996, (08) :961-962

[9] Intramolecular dehydrofluorinative coupling of the asymmetric diphosphine Ph2PCH2CH2PPh(C5F4N-4) and pentamethylcyclopentadienyl ligands in a rhodium complex [J].

Bellabarba, RM ;

Nieuwenhuyzen, M ;

Saunders, GC .

ORGANOMETALLICS, 2003, 22 (09) :1802-1810

[10] ETA(2)-COORDINATION AND C-F ACTIVATION OF HEXAFLUOROBENZENE BY CYCLOPENTADIENYLRHODIUM AND CYCLOPENTADIENYLIRIDIUM COMPLEXES [J].

BELT, ST ;

HELLIWELL, M ;

JONES, WD ;

PARTRIDGE, MG ;

PERUTZ, RN .

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1993, 115 (04) :1429-1440

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