Historically, there have been three methods for assembling enantiomerically-pure carbocycles: cyclization of an enantiomerically-pure starting material, enantioselective cyclization of a prochiral substrate, and enantioselective transformation of a prochiral cyclic starting…
Jin-Quan Yu of Cambridge University reports (Org. PMID:35567400 Lett. 2003, 5, 4665. DOI: 10.1021/ol0358509) that Pd nanoparticles catalyze the hydrogenolysis of benzylic epoxides. The reaction proceeds with inversion of absolute…
Green or sustainable chemistry has now attained the status of a major scientific discipline (Green Chemistry: Theory and Practice, 1998, Oxford Press) and the studies in this area have led…
Sharpless asymmetric epoxidation has long been a workhorse of enantioselective synthesis. The SAE protocol, however, gives only mediocre ee’s with cis allylic alcohols such as nerol (1). PMID:23381626 Hisashi Yamamoto…
Alcohols are the most common functional group protected, and benzyl is the most commonly used alcohol protecting group. Gregory B. Dudley of Florida State University has developed (J. Org. Chem.…
Last week (2006 Jan 23), aldol andMannich-based strategies for the catalytic enantioselective construction of extended arrays of aminated, oxygenated and alkylated stereogenic centers were reviewed. This week, the focus is…
The aza-Baylis-Hillman (aza-BH) reaction is a nucleophile-catalysed coupling of an imine with an electron-deficient olefin which provides direct access to highly functionalized chiral amines from readily available achiral starting materials.…
W. Edward Lendsell and Peter N. Preston of Herriot-Watt University, Edinburgh, have developed (Tetrahedron Lett. 2005, 46, 8695. DOI: 10.1016/j.tetlet.2005.10.038)a new family of Pd catalysts, exemplified by the complex 2.…
Strained three- and four-membered rings can be used to constructlarger rings. The release of the strain energy facilitates bond formation, and the stereochemistry of the small ring can be transmitted…
Chan-Mo Yu of Sungkyunkwan University, Suwon, has developed (Angew. Chem. Int. 3-Azidopropanoic acid uses Ed. 2006, 45, 1553. PMID:24580853 DOI: 10.1002/anie.200503863)a powerful strategy for assembling arrays of stereogenic centers, using…
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