Compartmentalization of incompatible reagents within Pickering emulsion droplets for one-pot cascade reactions

It is a dream that future synthetic chemistry can mimic living systems to process multistep cascade reactions in a one-pot fashion. One of the key challenges is the mutual destruction of incompatible or opposing reagents, for example, acid and base, oxidants and reductants. A conceptually novel strategy is developed here to address this challenge. This strategy is based on a layered Pickering emulsion system, which is obtained through lamination of Pickering emulsions. In this working Pickering emulsion, the dispersed phase can separately compartmentalize the incompatible reagents to avoid their mutual destruction, while the continuous phase allows other reagent molecules to diffuse freely to access the compartmentalized reagents for chemical reactions. The compartmentalization effects and molecular transport ability of the Pickering emulsion were investigated. The deacetalization–reduction, deacetalization–Knoevenagel, deacetalization–Henry and diazotization–iodization cascade reactions demonstrate well the versatility and flexibility of our strategy in processing the one-pot cascade reactions involving mutually destructive reagents

Compartmentalization of Incompatible Reagents within Pickering Emulsion Droplets for One-Pot Cascade Reactions

It is a dream that future synthetic chemistry can mimic living systems to process multistep cascade reactions in a one-pot fashion. One of the key challenges is the mutual destruction of incompatible or opposing reagents, for example, acid and base, oxidants and reductants. A conceptually novel strategy is developed here to address this challenge. This strategy is based on a layered Pickering emulsion system, which is obtained through lamination of Pickering emulsions. In this working Pickering emulsion, the dispersed phase can separately compartmentalize the incompatible reagents to avoid their mutual destruction, while the continuous phase allows other reagent molecules to diffuse freely to access the compartmentalized reagents for chemical reactions. The compartmentalization effects and molecular transport ability of the Pickering emulsion were investigated. The deacetalization–reduction, deacetalization–Knoevenagel, deacetalization–Henry and diazotization–iodization cascade reactions demonstrate well the versatility and flexibility of our strategy in processing the one-pot cascade reactions involving mutually destructive reagents

A Quantitative Description of the σ-Donor and π-Acceptor Properties of Substituted Phenanthrolines

4sinoneThe bond between molybdenum and substituted 1,10-phenanthroline ligands in a series of [Mo(CO)4(phen*)] complexes has been studied by combining experimental data (νCO) with DFT calculations. First, natural orbitals for chemical valence (NOCV) were calculated: The resulting charge-transfer magnitudes (Δqi) associated with the deformation density channels (Δρi) were related to σ-donation and π-back-donation. Then, energy decomposition analysis was performed by applying the extended transition state (ETS) scheme. The outcomes of the ETS-NOCV approach has allowed us to quantify the energetic contribution of both ligand-to-metal (Eσ) and metal-to ligand (Eπ) interactions. A new parameter (Tphen) has been introduced comprising both Eσ and Eπ and thus providing a descriptor for the overall electronic contribution given by phenanthrolines to the metal–ligand bond. This was corroborated by the linear correlation found between Tphen and the νCO vibration modes of [Mo(CO)4(phen*)] complexes, at least for those containing a 2,9-unsubstituted phenanthroline. The case of [Mo(CO)4(phen*)] derivatives with a 2,9-substituted phen* is also discussed.Ardizzoia, G.Attilio; Bea, Michela; Brenna, Stefano; Therrien, BrunoArdizzoia, GIAN ATTILIO; Bea, Michela; Brenna, Stefano; Therrien, Brun