A method for producing polymerisable solution which comprises dissolving an ethylenically unsaturated zwitterionic monomer in a co-monomer system comprising a functionalised ethylenically unsaturated monomer in which the zwitterionic monomer is soluble, a siloxane group-containing monomer or macromer, and a crosslinking agent is disclosed. The polymerisable solution is biocompatible and can be used to produce polymers and articles such as contact lenses.
Flash vacuum pyrolysis of dichlorophosphines over magnesium: Generation and reactivity of simple phosphinidenes
作者:R.Alan Aitken、Wayiza Masamba、Neil J Wilson
DOI:10.1016/s0040-4039(97)10236-2
日期:1997.12
Flash vacuum pyrolysis of dichlorophosphines over magnesium at 500–600 °C gives the products expected from intramolecular CH insertion of the corresponding phosphinidenes.
Oligodentate Phosphine Ligands with Phospholane End Groups: New Synthetic Access and Application to Molybdenum‐Based Synthetic Nitrogen Fixation
作者:Mareike Pfeil、Tobias A. Engesser、Alexander Koch、Jannik Junge、Jan Krahmer、Christian Näther、Felix Tuczek
DOI:10.1002/ejic.201901068
日期:2020.4.30
A new synthetic access to oligodentate phosphine ligands with phospholane end groups, starting from lithium phospholanide, is established. Based on this building block, the tridentate ligand prPP(Ph)P‐pln was synthesized and used for the synthesis of [MoX3prPP(Ph)P‐pln}] (X = Cl, Br, I) precursors. Sodium amalgam reduction in the presence of N2 and either mono‐ or bidentate ligands leads to several
NOVEL CATALYSTS FOR THE SYNTHESIS OF OLIGOMERIC ISOCYANATES
申请人:Covestro Intellectual Property GmbH & Co. KG
公开号:US20200369694A1
公开(公告)日:2020-11-26
The present invention relates to innovative catalysts for producing oligomeric polyisocyanates. These catalysts comprise polyhedral silsesquioxanes to which cyclic phosphorus(III) or phosphorus(V) compounds have been coupled.
Organic carbodiimides are prepared by heating isocyanates of formula R -- (NCO).sub.n wherein R is an organic radical and n is 1 or 2 In the presence of 2-methyl-2,5-dioxo-1-oxa-2-phospholane having the structure ##STR1## as catalyst as temperatures of about 50.degree. to 250.degree. C. The special catalyst not only gives good to excellent yields but, also allows the process to be carried out safely on an industrial scale.