A stereocontrolled approach to electrophilic epoxides
作者:Otto Meth-Cohn、Clive Moore、Heinrich C. Taljaard
DOI:10.1039/p19880002663
日期:——
Lithium t-butyl hydroperoxide (easily generated by addition of an alkyl-lithium to anhydrous t-butyl hydroperoxide in THF solution) is a powerful reagent for the epoxidation of electrophilic alkenes at –20 to 0 °C under full stereocontrol.
The invention provides epoxy and oxetane compositions including the novel acyloxy and N-acyl curing agents described herein. Use of invention curing agents result in cured adhesive compositions with remarkably increased adhesion and reduced hydrophilicity when compared to resins cured with other types of curing agents. Furthermore, the curatives of this invention do not interfere with free-radical cure and are thus suited for use in hybrid cure thermoset compositions.
Novel Base-Free Catalytic Wittig Reaction for the Synthesis of Highly Functionalized Alkenes
作者:Marie-Luis Schirmer、Sven Adomeit、Anke Spannenberg、Thomas Werner
DOI:10.1002/chem.201503744
日期:2016.2.12
base‐free catalytic Wittigreactions has been developed and optimized. Initially, several potential (pre)catalysts as well as different silanes as reducing agents were screened. A system based on a readily available phosphine oxide as precatalyst and trimethoxy silane as reducing agent proved to be optimal. The effect of various Brønsted acidic additives was studied. Subsequently, the reaction conditions were
The invention provides epoxy and oxetane compositions including the novel acyloxy and N-acyl curing agents described herein. Use of invention curing agents result in cured adhesive compositions with remarkably increased adhesion and reduced hydrophilicity when compared to resins cured with other types of curing agents. Furthermore, the curatives of this invention do not interfere with free-radical cure and are thus suited for use in hybrid cure thermoset compositions.
The invention provides epoxy and oxetane compositions including the novel acyloxy and N-acyl curing agents described herein. Use of invention curing agents result in cured adhesive compositions with remarkably increased adhesion and reduced hydrophilicity when compared to resins cured with other types of curing agents. Furthermore, the curatives of this invention do not interfere with free-radical cure and are thus suited for use in hybrid cure thermoset compositions.