RESUMO
Intramolecular amination of organoboronates occurs with a 1,2-metalate shift of an aminoboron "ate" complex to form azetidines, pyrrolidines, and piperidines. Bis(boronates) undergo site-selective amination to form boronate-containing azacycles. Enantiomerically enriched azacycles are formed with high stereospecificity.
RESUMO
A rearrangement reaction of biarylphosphine-supported Pd(II) complexes was employed to synthesize 1,3,5-triaryl 2,4,6-triisopropylbenzene compounds, a class of molecules that has not previously been reported. The strain of the central hexasubstituted ring was investigated via X-ray crystallography.
Assuntos
Calixarenos/síntese química , Paládio/química , Calixarenos/química , Catálise , Cristalografia por Raios X , Ligantes , Modelos Moleculares , Estrutura MolecularRESUMO
Over the past three decades, Pd-catalyzed cross-coupling reactions have become a mainstay of organic synthesis. In particular, catalysts derived from biaryl monophosphines have shown wide utility in forming C-N bonds under mild reaction conditions. This work summarizes a variety of C-N cross-coupling reactions using biaryl monophosphines as supporting ligands, with the goal of directing synthetic chemists towards the ligands and conditions best suited for a particular coupling.
RESUMO
In this report, we describe the application of palladium-based oxidative addition complexes (OACs) as effective precatalysts for C-N, C-O, and C-F cross-coupling reactions with a variety of (hetero)arenes. These complexes offer a convenient alternative to previously developed classes of precatalysts, particularly in the case of the bulkiest biarylphosphine ligands, for which palladacycle-based precatalysts do not readily form. The precatalysts described herein are easily prepared and stable to long-term storage under air.
