PNN ruthenium pincer complexes based on phosphinated 2,2′- dipyridinemethane and 2,2′-oxobispyridine. metal-ligand cooperation in cyclometalation and catalysis

Rigoberto Barrios-Francisco, Ekambaram Balaraman, Yael Diskin-Posner, Gregory Leitus, Linda J W Shimon, David Milstein

Research output: Contribution to journalArticle

24 Citations (Scopus)

Abstract

The synthesis of novel PNN ruthenium pincer complexes based on 2,2′-dipyridinemethane phosphine derivatives, as well as on 2,2′-oxobispyridine phosphine ligands, and their reactivity toward dearomatization and cyclometalation are described. The dearomatized compounds 7a,b undergo cyclometalation to yield complexes 8a,b. In order for cyclometalation to proceed, the coordination sphere around the Ru center has to rearrange, and this depends on the flexibility of the system, showing that the cyclometalation is qualitatively faster in the case of the dimethyl derivative 7a than in the case of the spyrocyclopentyl derivative 7b. The cyclometalation occurs diastereoselectively and leads to only one diastereomer of the cyclometalated compounds. In the case of the 2,2′-oxobispyridine complex 6c, the dearomatized complex was too unstable to be isolated; however it was possible to isolate and characterize a stable dicarbonyl-dearomatized ruthenium(II) complex, 9c, when the deprotonation was performed under a CO atmosphere. Dearomatization of 6a under CO also led to dicarbonyl-dearomatized ruthenium(II) complex 9a, which slowly rearranged into the dicarbonyl-aromatized ruthenium(0) complex 10a. These complexes were tested in catalytic alcohol-amine coupling, esterification of primary alcohols, and hydrogenation of secondary amides. Moderate activity was observed in hydrogenation of amides to alcohols and amines and low activity in the other transformations, owing mainly to the formation of stable cyclometalated compounds.

Original languageEnglish
Pages (from-to)2973-2982
Number of pages10
JournalOrganometallics
Volume32
Issue number10
DOIs
Publication statusPublished - May 24 2013

Fingerprint

phosphine
Ruthenium
Catalysis
ruthenium
catalysis
Metals
Ligands
ligands
alcohols
Alcohols
Carbon Monoxide
Derivatives
phosphines
Amides
metals
amides
Hydrogenation
hydrogenation
Amines
amines

ASJC Scopus subject areas

  • Organic Chemistry
  • Physical and Theoretical Chemistry
  • Inorganic Chemistry

Cite this

PNN ruthenium pincer complexes based on phosphinated 2,2′- dipyridinemethane and 2,2′-oxobispyridine. metal-ligand cooperation in cyclometalation and catalysis. / Barrios-Francisco, Rigoberto; Balaraman, Ekambaram; Diskin-Posner, Yael; Leitus, Gregory; Shimon, Linda J W; Milstein, David.

In: Organometallics, Vol. 32, No. 10, 24.05.2013, p. 2973-2982.

Research output: Contribution to journalArticle

Barrios-Francisco, Rigoberto ; Balaraman, Ekambaram ; Diskin-Posner, Yael ; Leitus, Gregory ; Shimon, Linda J W ; Milstein, David. / PNN ruthenium pincer complexes based on phosphinated 2,2′- dipyridinemethane and 2,2′-oxobispyridine. metal-ligand cooperation in cyclometalation and catalysis. In: Organometallics. 2013 ; Vol. 32, No. 10. pp. 2973-2982.
@article{b6fe665351524a289d817a032805e3e2,
title = "PNN ruthenium pincer complexes based on phosphinated 2,2′- dipyridinemethane and 2,2′-oxobispyridine. metal-ligand cooperation in cyclometalation and catalysis",
abstract = "The synthesis of novel PNN ruthenium pincer complexes based on 2,2′-dipyridinemethane phosphine derivatives, as well as on 2,2′-oxobispyridine phosphine ligands, and their reactivity toward dearomatization and cyclometalation are described. The dearomatized compounds 7a,b undergo cyclometalation to yield complexes 8a,b. In order for cyclometalation to proceed, the coordination sphere around the Ru center has to rearrange, and this depends on the flexibility of the system, showing that the cyclometalation is qualitatively faster in the case of the dimethyl derivative 7a than in the case of the spyrocyclopentyl derivative 7b. The cyclometalation occurs diastereoselectively and leads to only one diastereomer of the cyclometalated compounds. In the case of the 2,2′-oxobispyridine complex 6c, the dearomatized complex was too unstable to be isolated; however it was possible to isolate and characterize a stable dicarbonyl-dearomatized ruthenium(II) complex, 9c, when the deprotonation was performed under a CO atmosphere. Dearomatization of 6a under CO also led to dicarbonyl-dearomatized ruthenium(II) complex 9a, which slowly rearranged into the dicarbonyl-aromatized ruthenium(0) complex 10a. These complexes were tested in catalytic alcohol-amine coupling, esterification of primary alcohols, and hydrogenation of secondary amides. Moderate activity was observed in hydrogenation of amides to alcohols and amines and low activity in the other transformations, owing mainly to the formation of stable cyclometalated compounds.",
author = "Rigoberto Barrios-Francisco and Ekambaram Balaraman and Yael Diskin-Posner and Gregory Leitus and Shimon, {Linda J W} and David Milstein",
year = "2013",
month = "5",
day = "24",
doi = "10.1021/om400194w",
language = "English",
volume = "32",
pages = "2973--2982",
journal = "Organometallics",
issn = "0276-7333",
publisher = "American Chemical Society",
number = "10",

}

TY - JOUR

T1 - PNN ruthenium pincer complexes based on phosphinated 2,2′- dipyridinemethane and 2,2′-oxobispyridine. metal-ligand cooperation in cyclometalation and catalysis

AU - Barrios-Francisco, Rigoberto

AU - Balaraman, Ekambaram

AU - Diskin-Posner, Yael

AU - Leitus, Gregory

AU - Shimon, Linda J W

AU - Milstein, David

PY - 2013/5/24

Y1 - 2013/5/24

N2 - The synthesis of novel PNN ruthenium pincer complexes based on 2,2′-dipyridinemethane phosphine derivatives, as well as on 2,2′-oxobispyridine phosphine ligands, and their reactivity toward dearomatization and cyclometalation are described. The dearomatized compounds 7a,b undergo cyclometalation to yield complexes 8a,b. In order for cyclometalation to proceed, the coordination sphere around the Ru center has to rearrange, and this depends on the flexibility of the system, showing that the cyclometalation is qualitatively faster in the case of the dimethyl derivative 7a than in the case of the spyrocyclopentyl derivative 7b. The cyclometalation occurs diastereoselectively and leads to only one diastereomer of the cyclometalated compounds. In the case of the 2,2′-oxobispyridine complex 6c, the dearomatized complex was too unstable to be isolated; however it was possible to isolate and characterize a stable dicarbonyl-dearomatized ruthenium(II) complex, 9c, when the deprotonation was performed under a CO atmosphere. Dearomatization of 6a under CO also led to dicarbonyl-dearomatized ruthenium(II) complex 9a, which slowly rearranged into the dicarbonyl-aromatized ruthenium(0) complex 10a. These complexes were tested in catalytic alcohol-amine coupling, esterification of primary alcohols, and hydrogenation of secondary amides. Moderate activity was observed in hydrogenation of amides to alcohols and amines and low activity in the other transformations, owing mainly to the formation of stable cyclometalated compounds.

AB - The synthesis of novel PNN ruthenium pincer complexes based on 2,2′-dipyridinemethane phosphine derivatives, as well as on 2,2′-oxobispyridine phosphine ligands, and their reactivity toward dearomatization and cyclometalation are described. The dearomatized compounds 7a,b undergo cyclometalation to yield complexes 8a,b. In order for cyclometalation to proceed, the coordination sphere around the Ru center has to rearrange, and this depends on the flexibility of the system, showing that the cyclometalation is qualitatively faster in the case of the dimethyl derivative 7a than in the case of the spyrocyclopentyl derivative 7b. The cyclometalation occurs diastereoselectively and leads to only one diastereomer of the cyclometalated compounds. In the case of the 2,2′-oxobispyridine complex 6c, the dearomatized complex was too unstable to be isolated; however it was possible to isolate and characterize a stable dicarbonyl-dearomatized ruthenium(II) complex, 9c, when the deprotonation was performed under a CO atmosphere. Dearomatization of 6a under CO also led to dicarbonyl-dearomatized ruthenium(II) complex 9a, which slowly rearranged into the dicarbonyl-aromatized ruthenium(0) complex 10a. These complexes were tested in catalytic alcohol-amine coupling, esterification of primary alcohols, and hydrogenation of secondary amides. Moderate activity was observed in hydrogenation of amides to alcohols and amines and low activity in the other transformations, owing mainly to the formation of stable cyclometalated compounds.

UR - http://www.scopus.com/inward/record.url?scp=84878198154&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84878198154&partnerID=8YFLogxK

U2 - 10.1021/om400194w

DO - 10.1021/om400194w

M3 - Article

AN - SCOPUS:84878198154

VL - 32

SP - 2973

EP - 2982

JO - Organometallics

JF - Organometallics

SN - 0276-7333

IS - 10

ER -