Lombardo methylenation

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Lombardo methylenation
Named afterLuciano Lombardo
Reaction type Organic redox reaction

In organic chemistry, the Lombardo methylenation is a name reaction that allows for the methylenation of carbonyl compounds with the use of Lombardo's reagent, which is a mix of zinc, dibromomethane, and titanium tetrachloride. [1] [2] [3] [4] [5] [6] [7]

Applications

The Lombardo methylenation has been used in the total synthesis of tetrodotoxin [8] and hirustene. [9] [10]

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References

  1. Lombardo, Luciano (1982-07-27). "Methylenation of carbonyl compounds with ZnCH2Br2TiCl4. Application to gibberellins". Tetrahedron Letters. 23 (41): 4293–4296. doi:10.1016/S0040-4039(00)88728-6.
  2. Wang, Zerong (15 September 2010). Comprehensive Organic Name Reactions and Reagents. doi:10.1002/9780470638859.conrr397. ISBN   9780470638859.
  3. Kulinkovich, Oleg G.; Meijere, Armin de (2000-07-21). "1,n-Dicarbanionic Titanium Intermediates from Monocarbanionic Organometallics and Their Application in Organic Synthesis". Chemical Reviews. 100 (8): 2789–2834. doi:10.1021/cr980046z. PMID   11749306.
  4. Pine, Stanley H. (2004-08-15). "Carbonyl Methylenation and Alkylidenation Using Titanium-Based Reagents". Organic Reactions: 1–91. doi:10.1002/0471264180.or043.01. ISBN   0471264180.
  5. Hartley, Richard C.; Li, Jianfeng; Main, Calver A.; McKiernan, Gordon J. (2007-06-04). "Titanium carbenoid reagents for converting carbonyl groups into alkenes". Tetrahedron. 63 (23): 4825–4864. doi:10.1016/j.tet.2007.03.015.
  6. Luciano Lombardo (1987). "Methylenation of Carbonyl Compounds: (+)-3-Methylene-cis-p-menthane". Organic Syntheses. 65: 81. doi:10.15227/orgsyn.065.0081.
  7. Marsden, Stephen P.; Ducept, Pascal C. (2005). "Synthesis of highly substituted allenylsilanes by alkylidenation of silylketenes". Beilstein Journal of Organic Chemistry . 1 (1): 5. doi: 10.1186/1860-5397-1-5 . PMC   1399453 . PMID   16542018.
  8. Hinman, Andrew; Du Bois, Justin (2003-08-30). "A Stereoselective Synthesis of (−)-Tetrodotoxin". Journal of the American Chemical Society. 125 (38): 11510–11511. doi:10.1021/ja0368305. PMID   13129349.
  9. Ley, Steven V.; Murray, P. John (1982). "A short syntesis of (±)-hirsutene involving the use of an organoselenium-mediated cyclization reaction". Journal of the Chemical Society, Chemical Communications (21): 1252–1253. doi:10.1039/C39820001252.
  10. Ley, Steven V.; Murray, P. John; Palmer, Brian D. (1985-11-14). "Total synthesis of the sesquiterpene (±)-hirsutene using an organoselenium-mediated cyclization reaction". Tetrahedron. 41 (21): 4765–4769. doi:10.1016/S0040-4020(01)96715-8.