Timothy W. Wallace

Bio: Timothy W. Wallace is an academic researcher from University of Manchester. The author has contributed to research in topics: Cycloaddition & Bicyclic molecule. The author has an hindex of 21, co-authored 98 publications receiving 1271 citations. Previous affiliations of Timothy W. Wallace include University of Salford.

Biaryl synthesis with control of axial chirality

Abstract: Biaryls have been a persistent focus of interest for chemists since it was recognised, more than 80 years ago, that they can manifest the axial chirality that is inherent in structures consisting of intersecting dissymmetric planes. In recent decades their importance has risen steeply as this structural motif proved spectacularly successful in catalytic synthetic roles and was found to be significant in the context of biological activity. As a consequence, synthetic methods which allowed the construction of biaryls with axial stereocontrol have become highly desirable, and this article traces the development of non-resolution approaches to biaryls with a chosen axial configuration.

Biocatalytic Routes to Enantiomerically Enriched Dibenz[c,e]azepines.

Abstract: Biocatalytic retrosynthetic analysis of dibenz[c,e]azepines has highlighted the use of imine reductase (IRED) and ω-transaminase (ω-TA) biocatalysts to establish the key stereocentres of these molecules. Several enantiocomplementary IREDs were identified for the synthesis of (R)- and (S)-5-methyl-6,7-dihydro-5H-dibenz[c,e]azepine with excellent enantioselectivity, by reduction of the parent imines. Crystallographic evidence suggests that IREDs may be able to bind one conformer of the imine substrate such that, upon reduction, the major product conformer is generated directly. ω-TA biocatalysts were also successfully employed for the production of enantiopure 1-(2-bromophenyl)ethan-1-amine, thus enabling an orthogonal route for the installation of chirality into dibenz[c,e]azepine framework.

3d Transition Metals for C-H Activation.

Abstract: C–H activation has surfaced as an increasingly powerful tool for molecular sciences, with notable applications to material sciences, crop protection, drug discovery, and pharmaceutical industries, among others. Despite major advances, the vast majority of these C–H functionalizations required precious 4d or 5d transition metal catalysts. Given the cost-effective and sustainable nature of earth-abundant first row transition metals, the development of less toxic, inexpensive 3d metal catalysts for C–H activation has gained considerable recent momentum as a significantly more environmentally-benign and economically-attractive alternative. Herein, we provide a comprehensive overview on first row transition metal catalysts for C–H activation until summer 2018.