Selective Reactions of Alkenes
Chemexpress Alkenes are among the least expensive of organic functional groups. They are easily incorporated into a growing molecule, and are stable to many of the reagents that transform other functionality.…
Stereocontrolled Construction of Carbacycles
Intramolecular carbene insertion (e.g. 1 -> 3) has long been a useful method for ring construction. Masahisa Nakada of Waseda University in Tokyo now reports (J. Am. Chem. Soc. Buy5-Methoxyquinazolin-4(3H)-one…
Catalytic Asymmetric Synthesis of Quinine and Quinidine
The tetracyclic alkaloid quinine 1 and the diastereomeric alkaloid quinidine 2 share a storied history. Eric Jacobsen of Harvard recently completed (J. PMID:25027343 Buy2-Chloro-1H-indole Am. Chem. Soc. 2004, 126, 706.DOI:…
Creative Applications of Alkene and Alkyne Metathesis in Total Synthesis: (+)-8-epi-Xanthatin, (+)-Longicin, Latrunculin A, and Garsubellin A
Alkene and alkyne metathesis, well-developed synthetic methods, are now often employed in natural product synthesis. The total syntheses outlined here are noteworthy for their creative application of these reactions. Buy7-Amino-4-bromoisoindolin-1-one…
Selective Reactions of Alkenes
Diimide (H-N=N-H) is an effective reagent for reducing alkenes. Yasushi Imada and Takeshi Naota of Osaka University have devised (J. Am. Chem. Soc. 2005, 127, 14544. DOI: 10.1021/ja053976q)a flavin-catalyzed protocol…
Chiral N-Heterocyclic Carbenes
N-heterocyclic salts are air-stable crystalline solids that can be stored with no special precautions and are the precursors of N-Heterocyclic Carbenes (NHCs), which are produced upon treatment with an appropriate…
Transition Metal Mediated Carbocyclic Construction
Alkene and alkyne metathesis have, in a relatively short time, become important tools for organic synthesis. Carlos Saá of the Universidad de Santiago de Compostela has developed (J. Am. PMID:23927631…
Catalytic Enantioselective Construction of Alkylated Stereogenic Centers
One of the simplest ways to construct alkylated ternary centers is enantioselective catalytic hydrogenation. Xumu Zhang of Pennsylvania State University has devised (Angew. Chem. Int. Ed. 2005, 44, 4933. 1803603-34-0…
Stereoselective Construction of Nitrogen Heterocycles
Nitrogen heterocycles are the basis of many essential pharmaceuticals, and of many physiologically-active natural products. There is a continuing interest in the development of new methods for the construction of…
Functional Group Transformation
Two particularly useful conversions of alcohols were recently reported. PMID:23381601 Buy2,4,5-Trichloroquinoline Abdol Reza Hajipour of the University of Wisconsin has found (Tetrahedron Lett. 2006, 47, 4191.DOI: 10.1016/j.tetlet.2006.04.036)that grinding an alcohol…