Allylsilanes in the synthesis of three to seven membered rings: the silylcuprate strategy

• Asunción Barbero,
• Francisco J. Pulido and
• M. Carmen Sañudo

Beilstein J. Org. Chem. 2007, 3, No. 16, doi:10.1186/1860-5397-3-16

• groups in appropriate positions undergo silylcupration-ring formation, when treated with higher order cyanocuprates as (PhMe2Si)2CuCNLi2. Intramolecular trapping of the vinylcuprate intermediate allows the synthesis of methylenecyclopentanes 20–22 (Scheme 4). [14] Epoxidation of the oxoallylsilanes

The oxanorbornene approach to 3-hydroxy, 3,4-dihydroxy and 3,4,5-trihydroxy derivatives of 2-aminocyclohexanecarboxylic acid

• Ishmael B. Masesane,
• Andrei S. Batsanov,
• Judith A. K. Howard,
• Raju Mondal and
• Patrick G. Steel

Beilstein J. Org. Chem. 2006, 2, No. 9, doi:10.1186/1860-5397-2-9

• selectivity leading to exclusive formation of 12. In a similar fashion, and in agreement with the idea of two directing groups working in concert, epoxidation of the exo derived diene 5 afforded exclusive formation of epoxide 13. Speculating that disruption of any directing effects through the use of more

Synthesis and glycosidase inhibitory activity of new hexa- substituted C8-glycomimetics

• Olivia Andriuzzi,
• Christine Gravier-Pelletier,
• Gildas Bertho,
• Thierry Prangé and
• Yves Le Merrer

Beilstein J. Org. Chem. 2005, 1, No. 12, doi:10.1186/1860-5397-1-12

• aminocyclitols it could be an epoxidation followed by the nucleophilic opening of the epoxide moiety by a primary amine or another nitrogen nucleophile. Accordingly (Scheme 1), treatment of the fully O-protected L-ido-cyclooctene 1 with a 5 mol% aqueous solution of osmium(IV) tetroxide [34] in acetone in the

• epoxidation [35] of the cyclooctenes 1 and 2 (Scheme 2). Thus, treatment of 1 and 2 with meta-chloroperbenzoic acid in the presence of sodium hydrogen carbonate afforded the epoxides 7 and 8 in 91–96% yield. As precedently, because of the C2-axis of symmetry displayed by the L-ido or D-manno-cyclooctenes 1

Reagent controlled addition of chiral sulfur ylides to chiral aldehydes

• Varinder K. Aggarwal and
• Jie Bi

Beilstein J. Org. Chem. 2005, 1, No. 4, doi:10.1186/1860-5397-1-4

• respects it is surprising that the subtle effect of stereochemistry of the aldehyde has such a significant impact on the bond rotation step and therefore reversibility of betaine formation. Epoxidation of (+)-Glyceraldehyde with Sulfur Ylides Supporting Information Supporting Information File 28