C-C versus C-H activation and versus agostic C-C interaction controlled by electron density at the metal center

Mark Gandelman, Linda J W Shimon, David Milstein

Research output: Contribution to journalArticle

58 Citations (Scopus)

Abstract

Based on the PCN ligand 2, a remarkable degree of control over C-C versus C-H bond activation and versus formation of an agostic C-C complex was demonstrated by choice of cationic [Rh(CO)n(C2H 4)2-n] (n=0, 1, 2) precursors. Whereas reaction of 2 with [Rh(C2H4)2(solv)n]BF4 results in exclusive C-C bond activation to yield product 5, reaction with the dicarbonyl precursor [Rh(CO)2(solv)n]BF4 leads to formation of the C-H activated complex 9. The latter process is promoted by intramolecular deprotonation of the C-H bond by the hemilabile amine arm of the PCN ligand. The mixed monocarbonyl monoethylene Rh species [Rh(CO)(C 2H4)]BF4 reacts with the PCN ligand 2 to give an agostic complex 7. The C-C activated complex 5 is easily converted to the C-H activated one (9) by reaction with CO; the reaction proceeds by a unique sequence of 1,2-metal-to-carbon methyl shift, agostic interaction, and C-H activation processes. Similarly, the C-C agostic complex 7 is converted to the same C-H activated product 9 by treatment with CO.

Original languageEnglish
Pages (from-to)4295-4300
Number of pages6
JournalChemistry - A European Journal
Volume9
Issue number18
DOIs
Publication statusPublished - Sep 22 2003

Fingerprint

Pregnenolone Carbonitrile
Carrier concentration
Metals
Chemical activation
Ligands
Deprotonation
Amines
Carbon

Keywords

  • Agostic interactions
  • C-C activation
  • C-H activation
  • Carbonyl ligands
  • Dearomatization
  • Tridentate ligands

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

C-C versus C-H activation and versus agostic C-C interaction controlled by electron density at the metal center. / Gandelman, Mark; Shimon, Linda J W; Milstein, David.

In: Chemistry - A European Journal, Vol. 9, No. 18, 22.09.2003, p. 4295-4300.

Research output: Contribution to journalArticle

@article{4940bee1912b42089eee878734000275,
title = "C-C versus C-H activation and versus agostic C-C interaction controlled by electron density at the metal center",
abstract = "Based on the PCN ligand 2, a remarkable degree of control over C-C versus C-H bond activation and versus formation of an agostic C-C complex was demonstrated by choice of cationic [Rh(CO)n(C2H 4)2-n] (n=0, 1, 2) precursors. Whereas reaction of 2 with [Rh(C2H4)2(solv)n]BF4 results in exclusive C-C bond activation to yield product 5, reaction with the dicarbonyl precursor [Rh(CO)2(solv)n]BF4 leads to formation of the C-H activated complex 9. The latter process is promoted by intramolecular deprotonation of the C-H bond by the hemilabile amine arm of the PCN ligand. The mixed monocarbonyl monoethylene Rh species [Rh(CO)(C 2H4)]BF4 reacts with the PCN ligand 2 to give an agostic complex 7. The C-C activated complex 5 is easily converted to the C-H activated one (9) by reaction with CO; the reaction proceeds by a unique sequence of 1,2-metal-to-carbon methyl shift, agostic interaction, and C-H activation processes. Similarly, the C-C agostic complex 7 is converted to the same C-H activated product 9 by treatment with CO.",
keywords = "Agostic interactions, C-C activation, C-H activation, Carbonyl ligands, Dearomatization, Tridentate ligands",
author = "Mark Gandelman and Shimon, {Linda J W} and David Milstein",
year = "2003",
month = "9",
day = "22",
doi = "10.1002/chem.200304972",
language = "English",
volume = "9",
pages = "4295--4300",
journal = "Chemistry - A European Journal",
issn = "0947-6539",
publisher = "Wiley-VCH Verlag",
number = "18",

}

TY - JOUR

T1 - C-C versus C-H activation and versus agostic C-C interaction controlled by electron density at the metal center

AU - Gandelman, Mark

AU - Shimon, Linda J W

AU - Milstein, David

PY - 2003/9/22

Y1 - 2003/9/22

N2 - Based on the PCN ligand 2, a remarkable degree of control over C-C versus C-H bond activation and versus formation of an agostic C-C complex was demonstrated by choice of cationic [Rh(CO)n(C2H 4)2-n] (n=0, 1, 2) precursors. Whereas reaction of 2 with [Rh(C2H4)2(solv)n]BF4 results in exclusive C-C bond activation to yield product 5, reaction with the dicarbonyl precursor [Rh(CO)2(solv)n]BF4 leads to formation of the C-H activated complex 9. The latter process is promoted by intramolecular deprotonation of the C-H bond by the hemilabile amine arm of the PCN ligand. The mixed monocarbonyl monoethylene Rh species [Rh(CO)(C 2H4)]BF4 reacts with the PCN ligand 2 to give an agostic complex 7. The C-C activated complex 5 is easily converted to the C-H activated one (9) by reaction with CO; the reaction proceeds by a unique sequence of 1,2-metal-to-carbon methyl shift, agostic interaction, and C-H activation processes. Similarly, the C-C agostic complex 7 is converted to the same C-H activated product 9 by treatment with CO.

AB - Based on the PCN ligand 2, a remarkable degree of control over C-C versus C-H bond activation and versus formation of an agostic C-C complex was demonstrated by choice of cationic [Rh(CO)n(C2H 4)2-n] (n=0, 1, 2) precursors. Whereas reaction of 2 with [Rh(C2H4)2(solv)n]BF4 results in exclusive C-C bond activation to yield product 5, reaction with the dicarbonyl precursor [Rh(CO)2(solv)n]BF4 leads to formation of the C-H activated complex 9. The latter process is promoted by intramolecular deprotonation of the C-H bond by the hemilabile amine arm of the PCN ligand. The mixed monocarbonyl monoethylene Rh species [Rh(CO)(C 2H4)]BF4 reacts with the PCN ligand 2 to give an agostic complex 7. The C-C activated complex 5 is easily converted to the C-H activated one (9) by reaction with CO; the reaction proceeds by a unique sequence of 1,2-metal-to-carbon methyl shift, agostic interaction, and C-H activation processes. Similarly, the C-C agostic complex 7 is converted to the same C-H activated product 9 by treatment with CO.

KW - Agostic interactions

KW - C-C activation

KW - C-H activation

KW - Carbonyl ligands

KW - Dearomatization

KW - Tridentate ligands

UR - http://www.scopus.com/inward/record.url?scp=0141868817&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0141868817&partnerID=8YFLogxK

U2 - 10.1002/chem.200304972

DO - 10.1002/chem.200304972

M3 - Article

VL - 9

SP - 4295

EP - 4300

JO - Chemistry - A European Journal

JF - Chemistry - A European Journal

SN - 0947-6539

IS - 18

ER -