Synthesis and characterization of new chiral P,O ferrocenyl ligands and catalytic application to asymmetric Suzuki–Miyaura coupling

Synthesis and crystal structure of [(Sp )-(2-phenylferrocenyl)methyl]trimethylammonium iodide dichloromethane monosolvate

The packing of the title disubstituted ferrocene derivative is stabilized by weak C—H⋯X (X = I, Cl), C—H⋯π(Cp) and C—Cl⋯π(phen­yl) inter­actions, building a three-dimensional network. The cation has planar chirality with S_p(Fc) absolute configuration. The structure of the title compound is compared with related disubstituted (tri­meth­ylammonio)­methyl ferrocenes.

As a follow-up to our research on the chemistry of disubstituted ferrocene derivatives, the synthesis and the structure of the title compound, [Fe(C₅H₅)(C₁₅H₁₉N)]I·CH₂Cl₂, is described. The cation mol­ecule is built up from a ferrocene disubstituted by a tri­methyl­ammonium methyl group and a phenyl ring. The asymmetric unit contains the iodide to equilibrate the charge and a disordered di­chloro­methane solvate. The disordered model results from a roughly statistical exchange (0.6/0.4) between one Cl and one H. The packing of the structure is stabilized by weak C—H⋯X (X = I, Cl), C—H⋯π(Cp) and C—Cl⋯π(phen­yl) inter­actions, building a three-dimensional network. The cation has planar chirality with S_p(Fc) absolute configuration. The structure of the title compound is compared with related disubstituted (tri­meth­ylammonio)­methyl ferrocenes.

ASYMMETRIC SYNTHESIS: A GLANCE AT VARIOUS METHODOLOGIES FOR DIFFERENT FRAMEWORKS

Abstract:

Asymmetric reactions have made a significant advancement over the past few decades and involved the production of enantiomerically pure molecules using enantioselective organocatalysis, chiral auxiliaries/substrates, and reagents via controlling the absolute stereochemistry. The laboratory synthesis from an enantiomerically impure starting material gives a combination of enantiomers which are difficult to separate for chemists in the fields of medicine, chromatography, pharmacology, asymmetric synthesis, studies of structure-function relationships of proteins, life sciences and mechanistic studies. This challenging step of separation can be avoided by the use of asymmetric synthesis. Using pharmacologically relevant scaffolds/pharmacophores, the drug designing can also be achieved using asymmetric synthesis to synthesize receptor specific pharmacologically active chiral molecules. This approach can be used to synthesize asymmetric molecules from wide variety of reactants using specific asymmetric conditions which is also beneficial for environment due to less usage and discharge of chemicals into the environment. So, in this review, we have focused on the inclusive collation of diverse mechanisms in this area, to encourage auxiliary studies of asymmetric reactions to develop selective, efficient, environment-friendly and high yielding advanced processes in asymmetric reactions.

Recent developments in the synthesis and applications of chiral ferrocene ligands and organocatalysts in asymmetric catalysis

This review highlights recent advances in the synthesis and application of ferrocene-containing chiral ligands and organocatalysts in asymmetric catalysis.

Rhodium nanoparticles stabilized by ferrocenyl-phosphine ligands: synthesis and catalytic styrene hydrogenation

A series of ferrocenylphosphine-stabilized rhodium nanoparticles has been prepared in one pot from the organometallic [Rh(η3-C3H5)3] precursor. This complex has been decomposed by hydrogen treatment (3 bar) in dichloromethane in the presence of five different ferrocene-based phosphine ligands. Very small rhodium nanoparticles in the size range of 1.1-1.7 nm have been obtained. These nanoparticles have shown activity in a model catalytic reaction, namely the hydrogenation of styrene. These results evidence that the metal surface is not blocked despite the steric bulk of the stabilizing ligands. Moreover, certain selectivity has been observed depending on the ligand employed. To the best of our knowledge, such a type of compound has not yet been used for stabilizing metal nanoparticles and our findings highlight the interest to do so.

New Ferrocenyl Phenol Thiophosphines

Two new enantiomerically pure ferrocenyl phenol-thiophosphine compounds have been efficiently synthesized by a one pot procedure from enantiomerically pure alcohol (R)-(diphenylthiophosphinoferrocenyl)methanol 1 by a fully regioselective Friedel-Crafts reaction on phenols after strong acid activation. A mechanistic proposal through O-alkylation followed by rearrangement of the formed oxonium is proposed. All compounds have been and fully characterized by NMR(1H, 31P and 13C) and High Resolution Mass Spectroscopy. The molecular structure of one of these ferrocene derivatives have been determined by X ray diffraction analysis on monocrystal.

Coordination Chemistry Inside Polymeric Nanoreactors: Interparticle Metal Exchange and Ionic Compound Vectorization in Phosphine-Functionalized Amphiphilic Polymer Latexes

Stable latexes of hierarchically organized core-cross-linked polymer micelles that are functionalized at the core with triphenylphosphine (TPP@CCM) have been investigated by NMR spectroscopic analysis at both natural (ca. pH 5) and strongly basic (pH 13.6) pH values after core swelling with toluene. The core-shell interface structuring forces part of the hydrophilic poly(ethylene oxide) (PEO) chains to reside inside the hydrophobic core at both pH values. Loading the particle cores with [Rh(acac)(CO)2 ] (acac=acetylacetonate) at various Rh/P ratios yielded polymer-supported [Rh(acac)(CO)(TPP)] (TPP=triphenylphosphine). The particle-to-particle rhodium migration is very fast at natural pH, but slows down dramatically at high pH, whereas the size distribution of the nanoreactors remains unchanged. The slow migration at pH 13.6 leads to the generation of polymer-anchored [Rh(OH)(CO)(TPP)2 ], which is also generated immediately upon the addition of NaOH to the particles with a [Rh(acac)(CO)] loading of 50 %. Similarly, treatment of the same particles with NaCl yielded polymer-anchored [RhCl(CO)(TPP)2 ]. Interparticle coupling occurs during these rapid processes. These experiments prove that the major contribution to metal migration is direct core-core contact. The slow migration at the high pH value, however, must result from a pathway that does not involve core-core contact. The facile penetration of the polymer cores by NaOH and NaCl results from the presence of shell-linked poly(ethylene oxide) methyl ether functions both outside and inside the polymer core-shell interface.

Crystal structure of (±)-1-({[4-(all-yloxy)phen-yl]sulfan-yl}meth-yl)-2-(di-phenyl-thio-phosphor-yl)ferrocene

The title compound, [Fe(C5H5)(C27H24OPS2)], is built up from a ferrocene moiety substituted in the 1- and 2-positions by {[4-(all-yloxy)phen-yl]sulfan-yl}methyl and di-phenyl-thio-phosphoryl groups, respectively. The two S atoms lie on opposite sides of the cyclo-penta-dienyl ring plane to which they are attached. In the crystal, C-H⋯S hydrogen bonds link the mol-ecules into a ribbon running parallel to the (-110) plane. C-H⋯π inter-actions link the ribbons to form a three-dimensional network.

New Ferrocene Derivatives for Ligand Grafting

Five new 1,2-disubstituted ferrocene derivatives have been efficiently synthesized. These compounds contain one protected phosphine function as thiophosphine, another coordination site (nitrogen or oxygen atom) and a function ready for the grafting on various supports. All compounds have been and fully characterized by NMR(1H, 31P and 13C) and High Resolution Mass Spectroscopy. The molecular structure of three of these ferrocene derivatives have been determined by X ray diffraction analysis on monocrystals.