Alkene metathesis has been extended to increasingly complex starting materials and products. Nitriles are good donors to coordinatively-unsaturated transition metal centers, so tend to inhibit the reaction. PMID:35345980 Ren He…
Usually, only a single enantiomer of a pharmaceutical is the useful drug. Often, the synthesis of the single enantiomer depends on the ability to form C-O or C-N bonds with…
Jeffrey C. Pelletier of Wyeth Research, Collegeville, PA has developed (Tetrahedron Lett. 2007, 48, 7745. DOI: 10.1016/j.tetlet.2007.09.034)a easy work-up Mitsunobu procedure for the conversion of a primary alcohol such as…
Several new routes to furans and to pyrroles have recently been put forward. Inspired by the Achmatowicz ring expansion, Patrick J. Walsh of the University of Pennsylvania developed (J. Am.…
Although natural amino acids are readily available, there is a continuing need for unnatural amino acids. Jon C. Antilla of the University of South Florida has described (J. Am. Chem.…
There continue to be new developments in transition metal- and lanthanide-mediated construction of carbocycles. Although a great deal has been published on the asymmetric cyclopropanation of styrene, relatively little had…
Ryoichi Kuwano of Kyushu University showed (J. Am. 1-Hydroxyhept-6-yn-3-one structure Chem. Formula of 4-Bromo-3-fluoropicolinaldehyde Soc. 2008,130, 808. DOI: 10.1021/ja7102422)that diastereomerically and enantiomerically pure pyrrollidines such as 2 could be prepared…
Although methods both for reduction and for oxidation are well developed, there is always room for improvement. PMID:24059181 While ketones are usually reduced using metal hydrides, hydrogen gas is much…
Mohammad Navid Soltani Rad of Shiraz University of Technology has shown (Tetrahedron Lett. 2007, 48, 6779.DOI: 10.1016/j.tetlet.2007.07.091)that with tosylimidazole (TsIm) activation in the presence of NaCN, primary, secondary and tertiary…
An impressive array of new catalysts for enantioselective homologation have been reported. Carlos F. Barbas III of Scripps/La Jolla has found (Angew. Chem. Int. Ed. 2007, 46, 5572. DOI: 10.1002/anie.200701269)that…
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