Organic Chemistry Portal
Organic Chemistry Highlights

Monday, March 24, 2014
Eric D. Nacsa and Tristan H. Lambert
Columbia University

Oxidation

Huanfeng Jiang at the South China University of Technology developed (J. Am. Chem. Soc. 2013 135, 5286. DOI: 10.1021/ja401034g) the palladium-catalyzed dehydrogenative aminohalogenation of methyl acrylate with aniline 1. A 1,3-hydrogen shift/chlorination catalyzed by an iridium complex was reported (Angew. Chem. Int. Ed. 2013 52, 6273. DOI: 10.1002/anie.201301013) by Belén Martín-Matute at Stockholm University. Robert M. Waymouth discovered (J. Am. Chem. Soc. 2013 135, 7593. DOI: 10.1021/ja4008694) the chemoselective oxidation of polyol 5 by a cationic palladium species. A ruthenium(II) hydride was found to catalyze the conversion of alcohols such as 7 to carboxylic acids using water as the oxygen source as disclosed (Nature Chem. 2013 5, 122. DOI: 10.1038/nchem.1536) by David Milstein at the Weizmann Institute of Science in Israel.

Susan K. Hanson at the Los Alamos National Laboratory in New Mexico reported (Org. Lett. 2013 15, 650. DOI: 10.1021/ol303479f) the acceptorless dehydrogenation of alcohols catalyzed by cobalt complex 12 to form imines such as 13 upon reaction with an amine. A collaboration led by Pedro J. Pérez at the University of Huelva in Spain studied (J. Am. Chem. Soc. 2013 135, 3887. DOI: 10.1021/ja310866k) the oxidation of alkanes under catalysis with copper complex 15, primarily yielding alcohols and ketones, such as in the conversion of cyclohexane (14) to cyclohexanol (16) and cyclohexanone (17).

A remarkable symmetry-breaking Wacker oxidation of diene 18 to produce 19 was the key step in the total synthesis of (+)-obolactone reported (Org. Lett. 2013 15, 1294. DOI: 10.1021/ol400232m) by Reinhard Brückner at the University of Freiburg in Germany. Kiyotomi Kaneda at the University of Osaka found (Angew. Chem. Int. Ed. 2013 52, 5961. DOI: 10.1002/anie.201301611) that a palladium salt catalyzes the conversion of electron-deficient internal olefin 20 to ketone 21.

As part of a program to develop environmentally sustainable procedures, Caterina Fusco at the University of Bari in Italy described (Tetrahedron Lett. 2013 54, 515. DOI: 10.1016/j.tetlet.2012.11.074) the oxidative cleavage of lactam 22 by methyl(trifluoromethyl)dioxirane in water to produce ω-nitro acid 24. Motomu Kanai at the University of Tokyo reported (Org. Lett. 2013 15, 1918. DOI: 10.1021/ol400568u) the β-functionalization of tertiary aromatic amine 25 with nitroolefin 26 to produce 27 by iron catalysis.

Norio Shibata at the Nagoya Institute of Technology discovered (J. Am. Chem. Soc. 2013 135, 8782. DOI: 10.1021/ja402455f) a novel trifluoromethylthiolation reagent, iodonium ylide 29. In situ reduction of the more convenient trifluoromethanesulfonyl group by copper(I) functionalized enamine 28 at the α-position to generate 30. A team led by Vikram C. Purohit at Teva Pharmaceuticals in Pennsylvania found (Org. Lett. 2013 15, 1650. DOI: 10.1021/ol400432x) that iodoarenesulfonic acid 32 catalyzed an oxidative 1,2-shift of α-substituted styrene 31 to furnish ketone 33.

The oxidative coupling of acid 34 to alkyne 35 via an α-oxo gold carbene intermediate was reported (Angew. Chem. Int. Ed. 2013 52, 6508. DOI: 10.1002/anie.201301601) by Liming Zhang at the University of California, Santa Barabara. The steric nature of the ligand was critical since substituted piperidines such as that found in the optimal catalyst 36 gave higher efficiencies. Finally, Luc Neuville at the French National Centre for Scientific Research described (Org. Lett. 2013 15, 1752. DOI: 10.1021/ol400560m) a copper system that coupled amidine 39 with alkyne 40 to produce the highly substituted imidazole 41.

E. D. Nacsa, T. H. Lambert, Org. Chem. Highlights 2014, March 24.
URL: https://www.organic-chemistry.org/Highlights/2014/24March.shtm