Synthesis of Heteroaromatics
Chemexpress Yasutaka Ishii of Kansai University has developed (J. Org. PMID:24982871 Chem. 2007, 72, 8820. DOI: 10.1021/jo701635f)a novel route to furans, using a mixed-metal catalyst to effect condensation of an aldehyde…
Synthesis of Dysiherbaine (Hatakeyama), Jerangolid D (Markó) and (+)-Spirolaxine Me Ether (Trost)
Several new developments in enantioselective C-O ring construction have been applied in the syntheses of natural products. Buy3-(Hydroxymethyl)pyrrolidin-2-one To achieve control, the oxygenated quaternary center of dysiherbaine (9) must be…
Developments in Alkene Metathesis
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…
Best Synthetic Methods: Enantioselective Oxidation and Reduction
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…
Functional Group Transformations
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…
Preparation of Heteroaromatic Derivatives
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.…
Enantioselective Assembly of Aminated Stereogenic Centers
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.…
Transition Metal-Mediated Construction of Carbocycles: Dimethyl Gloiosiphone A (Takahashi), Pasteurestin A (Mulzer), and Pentalenene (Fox)
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…
Stereoselective C-N Ring Construction
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…
Best Synthetic Methods: Oxidation and Reduction
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…