Cascade reaction


Cascade reaction

A cascade reaction or tandem reaction or domino reaction is a consecutive series of intramolecular organic reactions which often proceed via highly reactive intermediates. It allows the organic synthesis of complex multinuclear molecules from a single acyclic precursor. The substrate contains many functional groups that take part in chemical transformations one at the time. Often a functional group is generated in situ from the previous chemical transformation. The definition includes the prerequisite intramolecular in order to distinguish this reaction type from a multi-component reaction. In this sense it differs from the definition of a biochemical cascade. The main advantages of a cascade reaction in organic synthesis are that the reaction is often fast due to its intramolecular nature, the reaction is also clean, displays high atom economy and does not involve workup and isolation of many intermediates.

A cascade reaction is sometimes called a living reaction because it shares some characteristics with a living polymerization. In cascade reactions one can identify an initiation site, a relay moiety and a termination moiety. Examples of cascade reactions are numerous (e.g. the Aldol-Tishchenko reaction) and especially so in alkyne chemistry (the Banert cascade to name just one) or polyolefin polycycloisomerizations. Other alkyne coupling reactions are classified based on common features such as type of compound synthesised, for instance the spiro mode cascade [1]:

spiro mode cascade reaction
spiro mode cascade

or the linear-fused mode cascade,[2] through application of the intramolecular Heck reaction:

linear fused cascade reaction

or the zipper mode cascade.[3]

Zipper mode cascade reaction

Other cascade reactions are included in Diels-Alder reactions, oxirane ring-opening reactions,[4][5][6] and Pauson–Khand reactions.[7]

An example of an oxirane cascade reaction is given by the synthesis of certain polyether ladder polymers [8]:

Ladder Polyether Synthesis

This type of ladder compounds are found in marine lifeforms such as red tide. The tri-epoxide is prepared from a triene through asymmetric Shi epoxidation and oxone as primary oxidizing agent. The hydroxyl group in the tri-epoxide is activated as a nucleophile by the presence of the base caesium carbonate The bulky trimethylsilyl groups make such that the polyether is formed with the correct stereochemistry and they are removed in situ by caesium fluoride.

References

  1. ^ Barry M. Trost and Yian Shi (1991). "A Pd-Catalyzed Zipper Reaction". J. Am. Chem. Soc. 113 (2): 701–703. doi:10.1021/ja00002a064. 
  2. ^ M. M. Abelman and L. E. Overman (1988). "Palladium-catalyzed polyene cyclizations of dienyl aryl iodides". J. Am. Chem. Soc. 110 (7): 2328–2329. doi:10.1021/ja00215a068. 
  3. ^ T. Sugihara, C. Coperet, Z. Owczarczyk, L. S. Harring and E.-i. Negishi (1994). "Deferred Carbonylative Esterification in the Pd-Catalyzed Cyclic Carbometalation-Carbonylation Cascade". J. Am. Chem. Soc. 116 (17): 7923–7924. doi:10.1021/ja00096a070. 
  4. ^ Ronald Grigg and Visuvanathar Sridharan (1998). "Heterocycles via Pd catalysed molecular queuing processes. Relay switches and the maximisation of molecular com plexity". Pure Appl. Chem. 70 (5): 1047–1057. doi:10.1351/pac199870051047. http://www.iupac.org/publications/pac/1998/pdf/7005x1047.pdf. 
  5. ^ Tandem Reaction Sequences Chris Borths MacMillan Group Meeting November 21, 2000 article
  6. ^ Xiaomin Jin Cook Group Feb. 11, 2005 Article
  7. ^ Nakcheol Jeong, Byung Ki Sung, Jin Sung Kim, Soon Bong Park, Sung Deok Seo, Jin Young Shin, Kyu Yeol In, and Yoon Kyung Choi (2002). "Pauson–Khand-type reaction mediated by Rh(I) catalysts". Pure Appl. Chem. 74 (1): 85–91. doi:10.1351/pac200274010085. http://www.iupac.org/publications/pac/2002/pdf/7401x0085.pdf. 
  8. ^ Graham L. Simpson, Timothy P. Heffron, Estíbaliz Merino, and Timothy F. Jamison (2006). "Ladder Polyether Synthesis via Epoxide-Opening Cascades Using a Disappearing Directing Group". J. Am. Chem. Soc. 128 (4): 1056–1057. doi:10.1021/ja057973p. PMID 16433504. 

Wikimedia Foundation. 2010.

Look at other dictionaries:

  • Cascade — A cascade is a type of waterfall or a series of waterfalls.Cascade may also refer to: Places North America* Cascade Range, a mountain range on the west coast of North America * Cascade Volcanoes, a grouping of volcanoes on the west coast of North …   Wikipedia

  • Cascade Ischémique — La cascade ischémique [1] [2] désigne une série de réactions biochimiques déclenchées dans le cerveau après plusieurs secondes à quelques minutes d ischémie cérébrale ou d irrigation sanguine insuffisante.[3] La plupart des neurones ischémiés… …   Wikipédia en Français

  • Cascade ischemique — Cascade ischémique La cascade ischémique [1] [2] désigne une série de réactions biochimiques déclenchées dans le cerveau après plusieurs secondes à quelques minutes d ischémie cérébrale ou d irrigation sanguine insuffisante.[3] La plupart des… …   Wikipédia en Français

  • Réaction immunitaire — Système immunitaire Un lymphocyte, principale composante du système immunitaire humain Le mot « immunité » vient du latin immunitas (« exempté de charge »). Le système immunitaire d un organisme est un ensemble coordonné d… …   Wikipédia en Français

  • Cascade ischémique — La cascade ischémique [1],[2] désigne une série de réactions biochimiques déclenchées dans le cerveau après plusieurs secondes à quelques minutes d ischémie cérébrale ou d irrigation sanguine insuffisante[3]. La plupart des neurones ischémiés… …   Wikipédia en Français

  • Cascade failure — A cascade failure is a series of events on the internet in which network traffic is severely impaired or halted, to or between larger sections of the internet, caused by failing or disconnected hardware or software. Somewhat similar to the more… …   Wikipedia

  • Réaction de Barton-Motherwell — La réaction de Barton Motherwell (ou décarboxylation de Barton Motherwell) est une séquence réactionnelle permettant d effectuer sélectivement une réduction d un acide carboxylique en alcane. Elle fut mise au point par Sir Derek Harold Richard… …   Wikipédia en Français

  • Nazarov cyclization reaction — The Nazarov cyclization reaction (often referred to as simply the Nazarov cyclization) is a chemical reaction used in organic chemistry for the synthesis of cyclopentenones. The reaction is typically divided into classical and modern variants,… …   Wikipedia

  • Banert cascade — The Banert cascade is an organic reaction in which an NH 1,2,3 triazole is prepared from a propargyl halide or sulfate and sodium azide in a dioxane water mixture at elevated temperatures. This cascade reaction is unusual because it consists of… …   Wikipedia

  • Prins reaction — are formed. HistoryThe original reactants employed by Dutch chemist Hendrik Jacobus Prins in his 1919 publication were styrene ( scheme 2 ), pinene, camphene, eugenol, isosafrole and anethole. In 1937 the reaction was investigated as part of a… …   Wikipedia


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.