RESUMO
The synthesis of a range of novel silyl-protected dioxaborinanes as a column- and bench-stable boron reagent were found to be advantageous to achieving good yields in palladium-catalysed cross-coupling reactions under standard conditions.
RESUMO
A one-pot protocol for the formation of 2-nitrobenzenesulfonylhydrazide (NBSH) from commercial reagents and subsequent alkene reduction is presented. The transformation is operationally simple and generally efficient for effecting diimide alkene reductions. A range of 16 substrates have been reduced, highlighting the unique chemoselectivity of diimide as a reduction system.
Assuntos
Alcenos/síntese química , Hidrazinas/síntese química , Imidas/síntese química , Nitrobenzenos/síntese química , Catálise , Cromatografia , Hidrazinas/química , Indicadores e Reagentes , Modelos Moleculares , Estrutura Molecular , Nitrobenzenos/química , Oxirredução , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
Kinetic resolution of racemic C-3 substituted pyrrolidine-2,5-diones has been achieved for the first time using highly efficient oxazaborolidine catalysts derived from cis-1-amino-indan-2-ol.
Assuntos
Compostos Aza/química , Compostos de Boro/química , Succinimidas/química , Catálise , Indanos/química , Cinética , Estereoisomerismo , Succinimidas/isolamento & purificaçãoRESUMO
A novel ferrocene-derived substrate for the ratiometric electrochemical detection of alkaline phosphatase (ALP) was designed and synthesised. It was demonstrated to be an excellent electrochemical substrate for the ALP-labelled enzyme-linked immunosorbent assay (ELISA).
Assuntos
Fosfatase Alcalina/análise , Técnicas de Química Analítica/métodos , Técnicas Eletroquímicas , Ensaio de Imunoadsorção EnzimáticaRESUMO
Signal transduction and signal amplification are both important mechanisms used within biological signalling pathways. Inspired by this process, we have developed a signal amplification methodology that utilises the selectivity and high activity of enzymes in combination with the robustness and generality of an organometallic catalyst, achieving a hybrid biological and synthetic catalyst cascade. A proligand enzyme substrate was designed to selectively self-immolate in the presence of the enzyme to release a ligand that can bind to a metal pre-catalyst and accelerate the rate of a transfer hydrogenation reaction. Enzyme-triggered catalytic signal amplification was then applied to a range of catalyst substrates demonstrating that signal amplification and signal transduction can both be achieved through this methodology.
RESUMO
A highly enantioselective (>95% ee) strategy to affect the desymmetrization of a maleimide has been performed by temporary attachment to an anthracene template followed by asymmetric reduction with an oxazaborolidine catalyst. A stereoablative over-reduction process was partially responsible for the high levels of enantioselectivity. Exemplification of the strategy by stereoselective functionalization and retro-Diels-Alder reaction provided the natural product pyrrolam A.
Assuntos
Maleimidas/química , Alcaloides de Pirrolizidina/síntese química , Antracenos/química , Catálise , Reação de Cicloadição , Estrutura Molecular , Alcaloides de Pirrolizidina/química , EstereoisomerismoRESUMO
Bridged flavinium organocatalysts have displayed efficacy in the diimide mediated reduction of enamides in aqueous conditions. This represents the first diimide reduction of an electron rich alkene and offers a clean alternative to the use of alkylating agents for N-alkylation.