Dötz reaction

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The Dötz reaction is the chemical reaction of an aromatic or vinylic alkoxy pentacarbonyl chromium carbene complex with an alkyne and carbon monoxide to give a Cr(CO)₃-coordinated substituted phenol.^[1][2][3] Several reviews have been published.^[4][5] It is named after the German chemist Karl Heinz Dötz (b. 1943).

The position of the substituents is highly predictable with the largest alkyne substituent (R_L) neighboring the phenol and the smallest alkyne substituent (R_S) neighboring the methoxy group.^[6][7] Hence, this reaction is more useful for terminal alkynes than internal alkynes.

The phenol can be liberated from the chromium complex by a mild oxidation, such as ceric ammonium nitrate or air oxidation.

Since this reaction can quickly generate complex phenolic compounds, the Dötz reaction has been used most often in the synthesis of natural products, especially Vitamine E and K.^[8][9]

[edit] References

1. ^  Dötz, K. H. Angew. Chem. Int. Ed. Engl. 1975, 14, 644-645. (doi:10.1002/anie.197506442)
2. ^  Dötz, K. H.; Dietz, R.; von Imhof, A.; Lorenz, H.; Huttner, G. Chem. Ber. 1976, 109, 2033.
3. ^  Timko, J. M.; Yamashita, A. Org. Syn., Coll. Vol. 9, p.1 (1998); Vol. 71, p.72 (1993). (Article)
4. ^  Dötz, K. H. Pure Appl. Chem. 1983, 55, 1689. (Review)
5. ^  Dötz, K. H. New J. Chem. 1990, 14, 433-445. (Review)
6. ^  Wulff, W. D.; Tang, P. C.; McCallum, J. S. J. Am. Chem. Soc. 1981, 103, 7677-7678. (doi:10.1021/ja00415a058)
7. ^  Chamberlin, S.; Wulff, W. D. J. Org. Chem. 1994, 59, 3047-3054. (doi:10.1021/jo00090a024)
8. ^  Manish, R.; Wulff, W. D. Org. Lett. 2004, 6, 329-332. (doi:10.1021/ol0360445)
9. ^  White, J. D.; Smits, H. Org. Lett. 2005, 7, 235-238. (doi:10.1021/ol047779s)