The Catellani Reaction, (+) LINOXEPIN

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 The Catellani Reaction, a superb C-H Activation reaction. This recent review http://bit.ly/1LMNaKM outlines the challenges and future opportunities. Enjoy! #organichemistry #catellanireaction #CHactivation


LINK
http://urlaa.com/Catellani-Reaction-Perspective.pdf

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3715096/
 lignan (+)-linoxepin 1 using domino C–H functionalization with an overall yield of 30 %. This synthesis is the first reported application of the palladium-catalyzed Catellani reaction in the synthesis of a complex natural product. We note that the optical rotation of the synthetic material is higher (+90.0; c=0.25, CHCl₃) than the reported value (+23.0; c=0.93, CHCl₃). All of the spectroscopic data of the final product are in complete agreement with the published data from the isolated material. It is noteworthy that Tietze and co-workers observed a higher optical rotation in their resolved material than was found in the isolated material (+96.1; c=0.61, CHCl₃).⁵ X-ray crystallographic analysis unambiguously confirms the reported structure of linoxepin (1). We are continuing to investigate the origin of the change in regioselectivity in the final Mizoroki Heck reaction and will provide further details as they become available.

Synthesis of (+)-linoxepin (1). a) PdCl₂ (20 mol %), PPh₃ (44 mol %), CsOAc (10.0 equiv), DMF, 75 °C, 4 h, 76 %.

 


 

ACADEMIC........................




The Catellani reaction was devised by Marta Catellani. It is Norbornene-mediated Ortho C-H functionalization consisting series of reaction.^[1] Norbornene acts as a catalyst in this reaction.^[2]

Reaction mechanism

Catellani reaction consist of a series of reaction and Norbornene acts as the catalyst in this reaction along with Palladium.^[3] Rhodium can also be used as a catalyst along with Norbornene instead of Palladium.^[4]

Different Steps of catellani reaction: 1. Oxidative addition 2. Carbopalledation with Norbornene 3. Palladocycle formation 4. Oxidative addition 5. Reductive elimination 6. Norbornene extrusion 7. Termination

Uses

Catellani reaction is used for polyfunctionalization of aromatic molecule. It has been used as a key step for synthesis of novel lignan (+)- linoxepin.^[5] It can also be used for synthesis of Rhazinal.^[6]

References

1. 
   

Catellani; et al. (1997). "Regioselektive Synthese o,o′-disubstituierter Vinylarene über einen komplexen Katalysecyclus". Angewandte Chemie 109 (1-2). doi:10.1002/ange.19971090146. Retrieved 26 December 2014.

Catellani; et al. (1997). "Regioselektive Synthese o,o′-disubstituierter Vinylarene über einen komplexen Katalysecyclus". Angewandte Chemie 109 (1-2). doi:10.1002/ange.19971090146. Retrieved 26 December 2014.

Catellani; et al. (1997). "Regioselektive Synthese o,o′-disubstituierter Vinylarene über einen komplexen Katalysecyclus". Angewandte Chemie 109 (1-2). doi:10.1002/ange.19971090146. Retrieved 26 December 2014.

Wu; et al. (2013). "An efficient method for the Heck–Catellani reaction of aryl halides". Chem. Commun. 49. doi:10.1039/C3CC46381H.

Weinstabl; et al. (16 Apr 2013). "Total Synthesis of (+)-Linoxepin by Utilizing the Catellani Reaction". Angewandte Chemie International Edition 52 (20). doi:10.1002/anie.201302327. Retrieved 26 December 2014.

6. Sui; et al. (June 2013). "Pd-Catalyzed Chemoselective Catellani Ortho-Arylation of Iodopyrroles: Rapid Total Synthesis of Rhazinal". J. Am. Chem. Soc 135 (25): 9318–9321. doi:10.1021/ja404494u. Retrieved 26 December 2014.

External links

• Total Synthesis of (+)-Linoxepin by Utilizing the Catellani Reaction

MORE........

 

 http://www.rsc.org/suppdata/cc/c3/c3cc46381h/c3cc46381h_2.pdf

[PDF]Catellani reaction experimental revised - Royal Society of ...

www.rsc.org/suppdata/cc/c3/c3cc46381h/c3cc46381h_2.pdf

Product isolation of Heck-Catellani Reaction of aryl chlorides and iodides ... 13C NMR spectra were obtained at 100 MHz on 400 MHz or 75 MHz on 300 MHz.



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