Twofold Ferrocene C–H Lithiations For One-Step Difunctionalizations

Advanced Application of Planar Chiral Heterocyclic Ferrocenes

This manuscript is reviewing the superior catalytic activity and selectivity of ferrocene ligands in a wide range of reactions: reduction of ketones, hydrogenation of olefins, hydroboration, cycloaddition, enantioselective synthesis of biaryls, Tsuji–Trost allylation. Moreover, the correlation between a ligand structure and its catalytic activity is discussed in this review.

Structural Motifs of Alkali Metal Superbases in Non-coordinating Solvents

Lochmann-Schlosser superbases (LSB) are a standard reagent in synthetic chemistry to achieve an exchange of a proton on an organic framework with an alkali metal cation, which in turn can be replaced by a wide range of electrophilic groups. In standard examples, the deprotonating reagent consists of an equimolar mixture of n-butyllithium and potassium t-butoxide. However, the nature of the reactive species could not be pinned down either for this composition or for similar mixtures with comparable high reactivity. Despite the poor solubility and the fierce reactivity, some insights into this mixture were achieved by some indirect results, comparison with chemically related systems, or skillful deductions. Recent results, mainly based on new soluble compounds, delivered structural evidence. These new insights lead to advanced and more detailed conclusions about the interplay of the involved components.

Remote Deprotometalation-Iodolysis of N,N-Diisopropyl-2-trimethylsilylferrocenecarboxamide: A New Route Toward 1,1′-Disubstituted Ferrocenes

The 1,1′-disubstitution is currently the most frequent substitution pattern encountered in the ferrocene series. Here an original access based on the remote deprotometalation of N,N-diisopropyl-2-trimethylsilylferrocenecarboxamide is reported. The key intermediate, 1′-iodo-N,N-diisopropylferrocenecarboxamide, was prepared in multiple grams and was further functionalized toward fifteen 1′-substituted iodoferrocenes.

Synthesis of 1,2-dicyanoferrocene by cyanation reactions

We report two synthetic pathways for the preparation of 1,2-dicyanoferrocene, in a search for new dinitrile-based precursors that could be useful in the synthesis of metallocene-containing azaporphyrins, as well as in catalysis. Both procedures include cyanation reactions as the key steps. Magnesiation of cyanoferrocene, followed by reaction with electrophilic tosyl cyanide, affords the target compound in only two synthetic steps from ferrocene. In addition, 1,2-dicyanoferrocene can be prepared by a three step procedure, which implies a twofold cyanation of 1,2-dibromoferrocene, using Zn(CN)[Formula: see text], in a biphasic medium and in the presence of bulky [Formula: see text]-BuXPhos-Pd-G3.