Acceleration of Enantioselective Cycloadditions Catalyzed by Second-Generation Chiral Oxazaborolidinium Triflimidates by Biscoordinating Lewis Acids
作者:Barla Thirupathi、Simon Breitler、Karla Mahender Reddy、E. J. Corey
DOI:10.1021/jacs.6b08018
日期:2016.8.31
oxazaborolidines by the strong acid triflimide (Tf2NH) in CH2Cl2 solution leads to highly active chiralLewis acids that are very effective catalysts for (4 + 2) cycloaddition. We report herein that this catalytic activity can be further enhanced by the use of Tf2NH in combination with the biscoordinating Lewis acid TiCl4 or SnCl4 as a coactivator. The effective increase in acidity of an exceedingly strong
Photoresist polymers of carboxyl-containing alicyclic compounds
申请人:Hyundai Electronics Industries Co., Ltd.
公开号:US06265130B1
公开(公告)日:2001-07-24
The present invention relates to a carboxyl-containing alicyclic compound represented by Chemical Formula 1:
wherein, R1 and R2, which may be identical to or different from each other, represent hydrogen or a tert-butyl group; X represents hydrogen, hydroxy or oxygen; and n represents a number from 1 to 3. Compounds of the present invention are useful as monomers in a photoresist resin, and in a process for preparing the same.
Synthesis of polycyclic homocyclopropylcarbinols by reductive cyclization of bromocyclopropyl epoxides
作者:Larry A. Last、E. Robert Fretz、Robert M. Coates
DOI:10.1021/jo00138a003
日期:1982.8
Structures providing low absorbing polymers at 157 nm wavelengths
申请人:——
公开号:US20040122179A1
公开(公告)日:2004-06-24
Monomers containing two or more hexafluoroisopropyl groups and containing plural saturated rings are polymerized to form polymers of high transparency optical properties at 157 nm wavelengths and improved etch resistance compared to polymers formed from single ring monomers.