Norbornadiene

Last updated
Norbornadiene
Norbornadiene.png
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Names
Preferred IUPAC name
Bicyclo[2.2.1]hepta-2,5-diene
Other names
2,5-Norbornadiene
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.004.066 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 204-472-0
PubChem CID
UNII
UN number 2251
  • InChI=1S/C7H8/c1-2-7-4-3-6(1)5-7/h1-4,6-7H,5H2
    Key: SJYNFBVQFBRSIB-UHFFFAOYSA-N
  • C1C2C=CC1C=C2
Properties
C7H8
Molar mass 92.14 g/mol
Density 0.906 g/cm3
Melting point −19 °C (−2 °F; 254 K)
Boiling point 89 °C (192 °F; 362 K)
Insoluble
Hazards
GHS labelling:
GHS-pictogram-flamme.svg
Danger
H225
P210, P233, P240, P241, P242, P243, P280, P303+P361+P353, P370+P378, P403+P235, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Norbornadiene is an organic compound and a bicyclic hydrocarbon. Norbornadiene is of interest as a metal-binding ligand, whose complexes are useful for homogeneous catalysis. It has been intensively studied owing to its high reactivity and distinctive structural property of being a diene that cannot isomerize (isomers would be anti-Bredt alkenes). Norbornadiene is also a useful dienophile in Diels-Alder reactions.

Contents

Synthesis

Norbornadiene can be formed by a Diels-Alder reaction between cyclopentadiene and acetylene [1]

Norbornadiene synthesis Norbornadiene synthesis.png
Norbornadiene synthesis

Reactions

Quadricyclane, a valence isomer, can be obtained from norbornadiene by a photochemical reaction when assisted by a sensitizer such as acetophenone: [2]

Synthesis of quadricyclane from norbornadiene.png

The norbornadiene-quadricyclane couple is of potential interest for solar energy storage when controlled release of the strain energy stored in quadricyclane back to norbornadiene is made possible. [3]

Norbornadiene is reactive in cycloaddition reactions. Norbornadiene is also the starting material for the synthesis of diamantane [4] and sumanene and it is used as an acetylene transfer agent for instance in reaction with 3,6-di-2-pyridyl-1,2,4,5-tetrazine. [5]

As a ligand

Norbornadiene is a versatile ligand in organometallic chemistry, where it serves as a two-electron or four-electron donor. (Norbornadiene)molybdenum tetracarbonyl is used as a source of "Mo(CO)4", exploiting the lability of the diene ligand in this case. [6] which is a useful source of "chromium tetracarbonyl," e.g. in reactions with phosphine ligands.

The norbornadiene analogue of cyclooctadiene rhodium chloride dimer has been used in homogeneous catalysis. Chiral, C2-symmetric dienes derived from norbornadiene have also been described. [7] [8]

See also

Related Research Articles

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<span class="mw-page-title-main">Diene</span> Covalent compound that contains two double bonds

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<span class="mw-page-title-main">Diels–Alder reaction</span> Chemical reaction

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References

  1. Orrego‐Hernández, Jessica; Hölzel, Helen; Quant, Maria; Wang, Zhihang; Moth‐Poulsen, Kasper (2021-10-14). "Scalable Synthesis of Norbornadienes via in situ Cracking of Dicyclopentadiene Using Continuous Flow Chemistry". European Journal of Organic Chemistry. 2021 (38): 5337–5342. doi:10.1002/ejoc.202100795. ISSN   1434-193X.
  2. Smith, Claiborune D. (1988). "Quadricyclane". Organic Syntheses ; Collected Volumes, vol. 6, p. 962.
  3. Gregory W. Sluggett; Nicholas J. Turro & Heinz D. Roth (1997). "Rh(III)-Photosensitized Interconversion of Norbornadiene and Quadricyclane". J. Phys. Chem. A . 101 (47): 8834–8838. Bibcode:1997JPCA..101.8834S. CiteSeerX   10.1.1.130.1791 . doi:10.1021/jp972007h.
  4. Diamantane in Organic Syntheses Coll. Vol. 6, p.378; Vol. 53, p.30 Online Article Archived 2012-07-28 at the Wayback Machine
  5. Ronald N. Warrener & Peter A. Harrison (2001). "π-Bond Screening in Benzonorbornadienes: The Role of 7-Substituents in Governing the Facial Selectivity for the Diels-Alder Reaction of Benzonorbornadienes with 3,6-Di(2-pyridyl)-s-Tetrazine" (PDF). Molecules . 6 (4): 353–369. doi: 10.3390/60400353 . PMC   6236418 . S2CID   53874105.
  6. Markus Strotmann; Rudolf Wartchow & Holger Butenschön (2004). "High yield synthesis and structures of some achiral and chiral (diphosphine)tetracarbonylchromium(0) chelate complexes with tetracarbonyl(norbornadiene)chromium(0) as complexation reagent". Arkivoc : KK–1112F.
  7. Ryo Shintani, Tamio Hayashi "Chiral Diene Ligands for Asymmetric Catalysis" Aldrich Chimica Acta 2009, vol. 42, number 2, pp. 31-38.
  8. Huang, Yinhua; Hayashi, Tamio (2022). "Chiral Diene Ligands in Asymmetric Catalysis". Chemical Reviews. 122 (18): 14346–14404. doi:10.1021/acs.chemrev.2c00218. PMID   35972018.