XPhos

Last updated
XPhos
XPhos.svg
Names
Preferred IUPAC name
Dicyclohexyl[2′,4′,6′-tris(propan-2-yl)[1,1′-biphenyl]-2-yl]phosphane
Other names
XPhos
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.123.428 OOjs UI icon edit-ltr-progressive.svg
PubChem CID
UNII
  • InChI=1S/C33H49P/c1-23(2)26-21-30(24(3)4)33(31(22-26)25(5)6)29-19-13-14-20-32(29)34(27-15-9-7-10-16-27)28-17-11-8-12-18-28/h13-14,19-25,27-28H,7-12,15-18H2,1-6H3 X mark.svgN
    Key: UGOMMVLRQDMAQQ-UHFFFAOYSA-N X mark.svgN
  • InChI=1/C33H49P/c1-23(2)26-21-30(24(3)4)33(31(22-26)25(5)6)29-19-13-14-20-32(29)34(27-15-9-7-10-16-27)28-17-11-8-12-18-28/h13-14,19-25,27-28H,7-12,15-18H2,1-6H3
    Key: UGOMMVLRQDMAQQ-UHFFFAOYAR
  • P(c2ccccc2c1c(cc(cc1C(C)C)C(C)C)C(C)C)(C3CCCCC3)C4CCCCC4
Properties
C33H49P
Molar mass 476.72
Appearancecolorless solid
Melting point 187 to 190 °C (369 to 374 °F; 460 to 463 K)
organic solvents
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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XPhos is a phosphine ligand derived from biphenyl. Its palladium complexes exhibit high activity for Buchwald-Hartwig amination reactions involving aryl chlorides and aryl tosylates. Both palladium and copper complexes of the compound exhibit high activity for the coupling of aryl halides and aryl tosylates with various amides. [1] It is also an efficient ligand for several commonly used C–C bond-forming cross-coupling reactions, including the Negishi, Suzuki, and the copper-free Sonogashira coupling reactions. It is especially efficient and general when employed as a (2-aminobiphenyl)-cyclometalated palladium mesylate precatalyst complex (Buchwald's third generation precatalyst system), XPhos-G3-Pd, which is commercially available and stable to bench storage. [2] [3] [4] The ligand itself also has convenient handling characteristics as a crystalline, air-stable solid. [5]

Contents

Structure

See also

Related Research Articles

The Heck reaction is the chemical reaction of an unsaturated halide with an alkene in the presence of a base and a palladium catalyst to form a substituted alkene. It is named after Tsutomu Mizoroki and Richard F. Heck. Heck was awarded the 2010 Nobel Prize in Chemistry, which he shared with Ei-ichi Negishi and Akira Suzuki, for the discovery and development of this reaction. This reaction was the first example of a carbon-carbon bond-forming reaction that followed a Pd(0)/Pd(II) catalytic cycle, the same catalytic cycle that is seen in other Pd(0)-catalyzed cross-coupling reactions. The Heck reaction is a way to substitute alkenes.

The Stille reaction is a chemical reaction widely used in organic synthesis. The reaction involves the coupling of two organic groups, one of which is carried as an organotin compound (also known as organostannanes). A variety of organic electrophiles provide the other coupling partner. The Stille reaction is one of many palladium-catalyzed coupling reactions.

The Suzuki reaction or Suzuki coupling is an organic reaction that uses a palladium complex catalyst to cross-couple a boronic acid to an organohalide. It was first published in 1979 by Akira Suzuki, and he shared the 2010 Nobel Prize in Chemistry with Richard F. Heck and Ei-ichi Negishi for their contribution to the discovery and development of noble metal catalysis in organic synthesis. This reaction is sometimes telescoped with the related Miyaura borylation; the combination is the Suzuki–Miyaura reaction. It is widely used to synthesize polyolefins, styrenes, and substituted biphenyls.

The Sonogashira reaction is a cross-coupling reaction used in organic synthesis to form carbon–carbon bonds. It employs a palladium catalyst as well as copper co-catalyst to form a carbon–carbon bond between a terminal alkyne and an aryl or vinyl halide.

Organopalladium chemistry is a branch of organometallic chemistry that deals with organic palladium compounds and their reactions. Palladium is often used as a catalyst in the reduction of alkenes and alkynes with hydrogen. This process involves the formation of a palladium-carbon covalent bond. Palladium is also prominent in carbon-carbon coupling reactions, as demonstrated in tandem reactions.

The Ullmann condensation or Ullmann-type reaction is the copper-promoted conversion of aryl halides to aryl ethers, aryl thioethers, aryl nitriles, and aryl amines. These reactions are examples of cross-coupling reactions.

The Negishi coupling is a widely employed transition metal catalyzed cross-coupling reaction. The reaction couples organic halides or triflates with organozinc compounds, forming carbon-carbon bonds (C-C) in the process. A palladium (0) species is generally utilized as the metal catalyst, though nickel is sometimes used. A variety of nickel catalysts in either Ni0 or NiII oxidation state can be employed in Negishi cross couplings such as Ni(PPh3)4, Ni(acac)2, Ni(COD)2 etc.

<span class="mw-page-title-main">Organozinc chemistry</span>

Organozinc chemistry is the study of the physical properties, synthesis, and reactions of organozinc compounds, which are organometallic compounds that contain carbon (C) to zinc (Zn) chemical bonds.

In organic chemistry, the Buchwald–Hartwig amination is a chemical reaction for the synthesis of carbon–nitrogen bonds via the palladium-catalyzed coupling reactions of amines with aryl halides. Although Pd-catalyzed C–N couplings were reported as early as 1983, Stephen L. Buchwald and John F. Hartwig have been credited, whose publications between 1994 and the late 2000s established the scope of the transformation. The reaction's synthetic utility stems primarily from the shortcomings of typical methods for the synthesis of aromatic C−N bonds, with most methods suffering from limited substrate scope and functional group tolerance. The development of the Buchwald–Hartwig reaction allowed for the facile synthesis of aryl amines, replacing to an extent harsher methods while significantly expanding the repertoire of possible C−N bond formations.

<span class="mw-page-title-main">1,1'-Bis(diphenylphosphino)ferrocene</span> Chemical compound

1,1-Bis(diphenylphosphino)ferrocene, commonly abbreviated dppf, is an organophosphorus compound commonly used as a ligand in homogeneous catalysis. It contains a ferrocene moiety in its backbone, and is related to other bridged diphosphines such as 1,2-bis(diphenylphosphino)ethane (dppe).

In organic chemistry, the Kumada coupling is a type of cross coupling reaction, useful for generating carbon–carbon bonds by the reaction of a Grignard reagent and an organic halide. The procedure uses transition metal catalysts, typically nickel or palladium, to couple a combination of two alkyl, aryl or vinyl groups. The groups of Robert Corriu and Makoto Kumada reported the reaction independently in 1972.

<span class="mw-page-title-main">SPhos</span> Chemical compound

SPhos is a phosphine ligand derived from biphenyl. Its palladium complexes exhibit high activity for Suzuki coupling reactions involving aryl chlorides, which are unreactive with palladium complexes of most other phosphine ligands. The ligand has convenient handling characteristics since it is air-stable.

In organic chemistry, a cross-coupling reaction is a reaction where two different fragments are joined. Cross-couplings are a subset of the more general coupling reactions. Often cross-coupling reactions require metal catalysts. One important reaction type is this:

<span class="mw-page-title-main">(1,1'-Bis(diphenylphosphino)ferrocene)palladium(II) dichloride</span> Chemical compound

[1,1'‑Bis(diphenylphosphino)ferrocene]palladium(II) dichloride is a palladium complex containing the bidentate ligand 1,1'-bis(diphenylphosphino)ferrocene (dppf), abbreviated as [(dppf)PdCl2]. This commercially available material can be prepared by reacting dppf with a suitable nitrile complex of palladium dichloride:

<span class="mw-page-title-main">PEPPSI</span> Group of chemical compounds

PEPPSI is an abbreviation for pyridine-enhanced precatalyst preparation stabilization and initiation. It refers to a family of commercially available palladium catalysts developed around 2005 by Prof. Michael G. Organ and co-workers at York University, which can accelerate various carbon-carbon and carbon-heteroatom bond forming cross-coupling reactions. In comparison to many alternative palladium catalysts, Pd-PEPPSI-type complexes are stable to air and moisture and are relatively easy to synthesize and handle.

<span class="mw-page-title-main">CPhos</span> Chemical compound

CPhos is a phosphine ligand derived from biphenyl. It is a white solid that is soluble in organic solvents.

<span class="mw-page-title-main">John P. Wolfe</span>

John Perry Wolfe is an American chemist and a professor of chemistry at the University of Michigan. He is best known for palladium-catalyzed C-C and C-N bond formation reactions. He was also one of the key scientists in the development of Buchwald ligands, one of which is appropriately named "JohnPhos" after him. Wolfe has taught at the University of Michigan since 2002.

<span class="mw-page-title-main">Palladium–NHC complex</span>

In organometallic chemistry, palladium-NHC complexes are a family of organopalladium compounds in which palladium forms a coordination complex with N-heterocyclic carbenes (NHCs). They have been investigated for applications in homogeneous catalysis, particularly cross-coupling reactions.

Dialkylbiaryl phosphine ligands are phosphine ligands that are used in homogeneous catalysis. They have proved useful in Buchwald-Hartwig amination and etherification reactions as well as Negishi cross-coupling, Suzuki-Miyaura cross-coupling, and related reactions. In addition to these Pd-based processes, their use has also been extended to transformations catalyzed by nickel, gold, silver, copper, rhodium, and ruthenium, among other transition metals.

Heterobimetallic catalysis is an approach to catalysis that employs two different metals to promote a chemical reaction. Included in this definition are cases where: 1) each metal activates a different substrate, 2) both metals interact with the same substrate, and 3) only one metal directly interacts with the substrate(s), while the second metal interacts with the first.

References

  1. Huang, X.; Anderson, K. W.; Zim, D.; Jiang, L.; Klapars, A.; Buchwald, S. L. (2003). "Expanding Pd-Catalyzed C-N Bond-Forming Processes: The First Amidation of Aryl Sulfonates, Aqueous Amination, and Complementarity with Cu-Catalyzed Reactions". J. Am. Chem. Soc. 125 (22): 6653–6655. doi:10.1021/ja035483w. PMID   12769573.
  2. Bruno, Nicholas C.; Tudge, Matthew T.; Buchwald, Stephen L. (2013-02-04). "Design and preparation of new palladium precatalysts for C–C and C–N cross-coupling reactions". Chemical Science. 4 (3): 916–920. doi:10.1039/C2SC20903A. ISSN   2041-6539. PMC   3647481 . PMID   23667737.
  3. Yang, Yang; Oldenhuis, Nathan J.; Buchwald, Stephen L. (2013). "Mild and General Conditions for Negishi Cross-Coupling Enabled by the Use of Palladacycle Precatalysts". Angew. Chem. Int. Ed. 52 (2): 615–619. doi:10.1002/anie.201207750. PMC   3697109 . PMID   23172689.
  4. Gelman, Dmitri; Buchwald, Stephen L. (2003). "Efficient Palladium-Catalyzed Coupling of Aryl Chlorides and Tosylates with Terminal Alkynes: Use of a Copper Cocatalyst Inhibits the Reaction". Angew. Chem. Int. Ed. 42 (48): 5993–5996. doi:10.1002/anie.200353015. PMID   14679552.
  5. Altman, R.A.; Fors, B.P.; Buchwald, S.L. (2007). "Pd-Catalyzed Amination Reactions of Aryl Halides Using Bulky Biarylmonophosphine Ligands". Nature Protocols . 2 (11): 2881–2887. doi:10.1038/nprot.2007.414. PMID   18007623. S2CID   23134711.