CO Reduction at a Borane-Modified Iron Complex: A Secondary Coordination Sphere Strategy.

This work addresses fundamental questions that deepen our understanding of secondary coordination sphere effects on carbon dioxide (CO) reduction using derivatized hydride analogues of the type, [Cp*Fe(diphosphine)H] (Cp* = CMe ) - a well-studied family of organometallic complex - as models. More precisely, we describe the general reactivity of [(Cp*-BR)Fe(diphosphine)H], which contains an intramolecularly positioned Lewis acid, and its cooperative reactivity with CO. Control experiments underscore the critical nature of borane incorporation for transforming CO to reduced products, a reaction that does not occur for unfunctionalized [Cp*Fe(diphosphine)H].

Oxidatively-induced C(sp)-C(sp) bond formation at a tucked-in iron(iii) complex.

Carbon-carbon (C-C) bond formation is a cornerstone of synthetic chemistry, relying on routes such as transition-metal mediated cross-coupling for the introduction of new carbon-based functionality. For {[M] -C} (M = metal) structural units, studies that offer well-defined relationships between metal oxidation state, hydrocarbon strain, and {[M] -C} bond thermochemistry are thus informative, providing a means to reliably access new product classes. Here, we show that one-electron oxidation of the iron tucked-in complex [(η-CMe[double bond, length as m-dash]CH)Fe(dppe)] (dppe = 1,2-bis(di--propylphosphino)ethane) results in C(sp)-C(sp) bond formation giving unique {Fe} dimers.

A Blueprint for Secondary Coordination Sphere Editing: Approaches Toward Lewis-Acid Assisted Carbon Dioxide Co-Activation.

Carbon dioxide (CO) is a potent greenhouse gas of environmental concern. Seeking to offer a solution to the "CO-problem", the chemistry community has turned a focus toward transition metal complexes which can activate, reduce, and convert CO into carbon-based products. The design of such systems involves judicious selection of both metal and accompanying donor ligand; in part, these efforts are motivated by biological metalloenzymes that undertake similar transformations.

An Investigation of Allyl-Substituted Bis(Diphosphine) Iron Complexes: Towards Precursors for Cooperative CO Activation.

In developing homogenous catalysts capable of CO activation, interaction with a metal center is often imperative. This work provides primary efforts towards the cooperative activation of CO using a Lewis acidic secondary coordination sphere (SCS) and iron via a paired theoretical/experimental approach. Specifically, this study reports efforts towards [Fe(diphosphine) (N )] as a CO -coordinated synthon where diphosphine=1,2-bis(di(3-cyclohexylboranyl)propylphosphino)ethane) (P B ) or its precursor, 1,2-bis(diallylphosphino)ethane (tape).