Organic Chemistry Portal
Organic Chemistry Highlights

Monday, May 23, 2011
Douglass F. Taber
University of Delaware

Oxidation and Reduction

Kiyotomi Kaneda of Osaka University devised (Angew. Chem. Int. Ed. 2010, 49, 5545. DOI: 10.1002/anie.201001055) gold nanoparticles that efficiently deoxygenated an epoxide 1 to the alkene 2. Robert G. Bergman of the University of California, Berkeley and Jonathan A. Ellman, now of Yale University, reported (J. Am. Chem. Soc. 2010, 132, 11408. DOI: 10.1021/ja103436v) a related protocol for deoxygenating 1,2-diols. Dennis A. Dougherty of Caltech established (Org. Lett. 2010, 12, 3990. DOI: 10.1021/ol1015493) that an acid chloride 3 could be reduced to the phosphonate 4.

Pei-Qiang Huang of Xiamen University effected (Synlett 2010, 1829. DOI: 10.1055/s-0030-1258111) reduction of an amide 5 by activation with Tf2O followed by reduction with NaBH4. André B. Charette of the Université de Montreal described (J. Am. Chem. Soc. 2010, 132, 12817. DOI: 10.1021/ja105194s) parallel results with Tf2O/Et3SiH. David Milstein of the Weizmann Institute of Science devised (J. Am. Chem. Soc. 2010, 132, 16756. DOI: 10.1021/ja1080019) a Ru catalyst for the alternative reduction of an amide 7 to the amine 8 and the alcohol 9.

Shi-Kai Tian of the University of Science and Technology of China effected (Chem. Commun. 2010, 46, 6180. DOI: 10.1039/C0CC00765J) reduction of a benzylic sulfonamide 10 to the hydrocarbon 11. Thirty years ago, S. Yamamura of Nagoya University reported (Chem. Commun. 1967, 1049. DOI: 10.1039/C19670001049) the efficient reduction of a ketone to the corresponding methylene with Zn/HCl. Hirokazu Arimoto of Tohoku University established (Tetrahedron Lett. 2010, 51, 4534. DOI: 10.1016/j.tetlet.2010.06.102) that a modified Zn/TMSCl protocol could be used following ozonolysis to effect conversion of an alkene 12 to the methylene 13.

José Barluenga and Carlos Valdés of the Universidad de Oviedo effected (Angew. Chem. Int. Ed. 2010, 49, 4993. DOI: 10.1002/anie.201001704) reduction of a ketone to the ether 16 by way of the tosylhydrazone 14. Kyoko Nozaki and Makoto Yamashita of the University of Tokyo and Dennis P. Curran of the University of Pittsburgh found (J. Am. Chem. Soc. 2010, 132, 11449. DOI: 10.1021/ja105277u) that the hydride 18 (actually a complex dimer) could effect the direct reduction of a halide 17, and also function as the hydrogen atom donor for free radical reduction, and as the hydride donor for the Pd-mediated reduction of an aryl halide.

Masayuki Inoue, also of the University of Tokyo used (Org. Lett. 2010, 12, 4195. DOI: 10.1021/ol1018079) Cl3CCN to promote MCPBA oxidation of an ether 20 to the ketone 21. Kandikere Ramaiah Prabhu of the Indian Institute of Technology, Bangalore oxidized (Angew. Chem. Int. Ed. 2010, 49, 6622. DOI: 10.1002/anie.201002635) a primary azide 22 to the nitrile 23 using commercial aqueous t-BuOOH. Debashis Chakraborty of the Indian Institute of Technology, Madras found (Tetrahedron Lett. 2010, 51, 3521. DOI: 10.1016/j.tetlet.2010.04.101) that commercial aqueous t-BuOOH could also be used to oxidize an aldehyde 24 to the acid 25. Masahito Ochiai of the University of Tokushima and Waro Nakanishi of Wakayama University devised (J. Am. Chem. Soc. 2010, 132, 9236. DOI: 10.1021/ja104330g) the reagent 26 to effect oxidation of the aldehyde 24 to the Baeyer-Villiger product 27.

Jonathan M. J. Williams of the University of Bath used (Org. Lett. 2010, 12, 5096. DOI: 10.1021/ol101978h) hydroxylamine to oxidize an aldehyde 28 to the amide 30. Jörg Sedelmeier, Steven V. Ley and Marcus Baumann of the University of Cambridge established (Org. Lett. 2010, 12, 3618. DOI: 10.1021/ol101345z) that flow conditions could be used to oxidize a nitro derivative 31 to the aldehyde 32, or (not illustrated) to the corresponding carboxylic acid or (from a secondary nitro) the ketone.

D. F. Taber, Org. Chem. Highlights 2011, May 23.