Diols obtained via chemo and regioselective ring opening of epoxy alcohols: a straightforward synthesis of 2S,3S-Octandiol
摘要:
Epoxy alcohols are regio and chemoselectively opened to the corresponding iodohydrins and then reduced in situ to diols; the application of the described procedure leads to a short asymmetric synthesis of a well known pheromone. Also homoallylic (E and Z) epoxy alcohols and its benzylated derivatives shows high preference for regioselective opening affording the corresponding 1,3 diol.
Peripheral functionalisation of dendrimers with polyoxotungstate complexes assembled by ionic bonding and their use as oxidation catalysts: Influence of the tether length
作者:Sylvain Nlate、Lauriane Plault、Didier Astruc
DOI:10.1039/b616288f
日期:——
poly-ammonium salts. Reactions of the latter with H3PW12O40 in the presence of hydrogenperoxide led to dendrimers containing PO4[WO(O2)2]4}3− species at the periphery. These compounds are efficient catalysts for the selectiveoxidation of alkenes, sulfides and alcohols in an aqueous–CDCl3 biphasic system, using hydrogenperoxide as the primary oxidant. The complexes with dendritic wedges directly bonded
The diastereoselective epoxidation of olefins in supercritical carbon dioxide
作者:Geoffrey R Haas、Joseph W Kolis
DOI:10.1016/s0040-4039(98)01212-x
日期:1998.8
CO2. The metal catalyst was prepared in a simple two step, Schiff base reaction to form the salen ligand, followed by complexation to the vanadyl group. The epoxidation reactions are clean and give both high yields and good diastereoselectivity.
The [RuH2(PPh3)4] catalysed condensation of nitriles with alcohols in the presence of 1–2 equiv. of water proceeds under neutral conditions to give the corresponding esters and lactones highly efficiently along with evolution of ammonia.
A variety of cyclic and acyclic allylic alcohols undergo efficient chemo-, regio- and/or stereoselective epoxidations in neutral aqueous solutions of amphiphilic carbohydrates (sucrose, L-arabinose, methyl or ethyl beta-D-fructopyranoside) by using dilute hydrogen peroxide in the presence of molybdic or tungstic salts.
Site-Specific Synthesis and Reactivity of Oligonucleotides Containing Stereochemically Defined 1,<i>N</i><sup>2</sup>-Deoxyguanosine Adducts of the Lipid Peroxidation Product <i>trans</i>-4-Hydroxynonenal
作者:Hao Wang、Ivan D. Kozekov、Thomas M. Harris、Carmelo J. Rizzo
DOI:10.1021/ja0288800
日期:2003.5.1
is a major peroxidation product of omega-6 polyunsaturated fatty acids. The reaction of HNE with DNA gives fourdiastereomeric 1,N(2)-gamma-hydroxypropano adducts of deoxyguanosine; background levels of these adducts have been detected in animal tissue. Stereospecificsyntheses of these four adducts at the nucleoside level have been accomplished. In addition, a versatile strategy for their site-specific