Bronsted acids of anionic chiral Co(III) complexes were found to act as efficient phase-transfer catalysts for the diastereoselective iodoglycosylation or iodocarboxylation of glycals with a variety of alcohols or carboxylic acids, respectively, with N-iodosuccinimide as the iodo cation source. The corresponding 2-deoxy-2-iodoglycosides, including monosaccharides and disaccharides, and 2-deoxy-2-iodoglycosyl
Copper mediated iodoacetoxylation and glycosylation: effective and convenient approaches for the stereoselective synthesis of 2-deoxy-2-iodo glycosides
作者:Suresh Kumar Battina、Sudhir Kashyap
DOI:10.1016/j.tetlet.2016.01.035
日期:2016.2
Copper(II) triflate catalyzed stereoselective glycosylation of 2-iodo-glycosyl acetate donor is reported. Anomeric activation of 2-deoxy-1-O-acetyl sugar employing Cu(OTf)2 found to be an attractive as well effective alternative reagent to the most frequently used triflic acid (TfOH) source such as TMSOTf or TBSOTf. Scope of the reaction was explored for various aglycones. This protocol involves simple
Reaction of Alkenes with Hydrogen Peroxide and Sodium Iodide: A Nonenzymatic Biogenic-Like Approach to Iodohydrins
作者:José Barluenga、María Marco-Arias、Francisco González-Bobes、Alfredo Ballesteros、José M. González
DOI:10.1002/chem.200305582
日期:2004.4.2
An efficient protocol to synthesize iodohydrins from alkenes is presented. Reactions were conducted in aqueous media using safe and readily available sodiumiodide (the most abundant form of the element), and a highly convenient oxidant such as hydrogen peroxide. Addition of a protic acid triggers a faster and efficient process, a role formally related to that played by haloperoxidase enzymes in naturally
Iodosobenzene diacetate-Iodine and IBX-Iodine: Reagent systems for the synthesis of diastereomerically enriched 2-deoxy-2-iodoglycosyl acetates and 2-deoxy-2-iodoglycosyl ortho-iodobenzoates from protected glycals
作者:Puli Saidhareddy、Sama Ajay、Arun K. Shaw
DOI:10.1016/j.tet.2017.06.001
日期:2017.7
stereoselective synthesis of trans-2-deoxy-2-iodoglycosylacetates and O-iodobenzoates respectively from differently protectedglycals have been developed. They are compatible with a variety of protecting groups and various functional groups at 2C-position. Hexose-3,2-enolone 8 is obtained directly from 2-acetoxy glycal 5 by method A. An application to modified method B has been shown by synthesis of a diastereomerically
A New Procedure for Highly Regio‐ and Stereoselective Iodoacetoxylation of Protected Glycals and α‐1,2‐Cyclopropanated Sugars
作者:David W. Gammon、Henok H. Kinfe、Dirk E. De Vos、Pierre A. Jacobs、Bert F. Sels
DOI:10.1080/07328300701351524
日期:2007.5.31
less than 2 h at low temperatures to 2‐deoxy‐2‐iodoglycosyl acetates or novel 2‐deoxy‐2‐iodomethylglycosyl acetates using the simple, inexpensive reagent mixture of ammonium iodide, hydrogen peroxide, and acetic anhydride/aceticacid in acetonitrile. The protected glycals gave rise to 2‐deoxy‐2‐bromoglycosyl acetates when ammoniumbromide was used instead of the iodide, although longer reaction times