(Thio)urea Organocatalyst Equilibrium Acidities in DMSO
摘要:
Bordwell's method of overlapping indicators was used to determine the pK(a) values of some of the most popular (thio)urea organocatalysts via UV spectrophotometric titrations. The incremental effect of CF3 groups on acidic strength was also investigated. The pic's are in the range of 8.5-19.6. The results may lead to a better understanding of noncovalent organocatalysis and may aid in future catalyst development.
Broensted correlations for electron transfer from carbanions to halomethyl phenyl sulfone and 1,1-dinitroalkane-type acceptors
作者:Frederick G. Bordwell、Anthony H. Clemens
DOI:10.1021/jo00134a003
日期:1982.6
BORDWELL F. G.; HUGHES D. L., J. ORG. CHEM., 1980, 45, NO 16, 3314-3320
作者:BORDWELL F. G.、 HUGHES D. L.
DOI:——
日期:——
(Thio)urea Organocatalyst Equilibrium Acidities in DMSO
作者:Gergely Jakab、Carlo Tancon、Zhiguo Zhang、Katharina M. Lippert、Peter R. Schreiner
DOI:10.1021/ol300307c
日期:2012.4.6
Bordwell's method of overlapping indicators was used to determine the pK(a) values of some of the most popular (thio)urea organocatalysts via UV spectrophotometric titrations. The incremental effect of CF3 groups on acidic strength was also investigated. The pic's are in the range of 8.5-19.6. The results may lead to a better understanding of noncovalent organocatalysis and may aid in future catalyst development.
Base-Promoted Oxidative C(sp<sup>3</sup>
)-S Bond Cross-Coupling of Inactive Fluorenes and Thiols for the Synthesis of 9-Monothiolated Fluorenes
A highly efficient and selective C(sp3)–S bond cross‐coupling method for the synthesis of 9‐thiolated fluorenes through a direct thiolation at 9‐C(sp3)–H of fluorenes with thiols is described.