Diastereoselective Synthesis of N-Substituted Planar Chiral Ferrocenes Using a Proline Hydantoin-Derived Auxiliary

Enantioselective Synthesis of Chiral Substituted 2,4-Diketoimidazolidines and 2,5-Diketopiperazines via Asymmetric Hydrogenation

An enantioselective hydrogenation of 5-alkylidene-2,4-diketoimidazolidines (hydantoins) and 3-alkylidene-2,5-ketopiperazines catalyzed by the Rh/f-spiroPhos complex under mild conditions has been developed, which provides an efficient approach to the highly enantioselective synthesis of chiral hydantoins and 2,5-ketopiperazine derivatives with high enantioselectivities up to 99.9% ee.

Iodoferrocene as a partner inN-arylation of amides

A general copper-promoted amidation of iodoferrocene is described toward original scaffolds that can be further functionalized by cross-coupling 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.

Revisiting the Urech Synthesis of Hydantoins: Direct Access to Enantiopure 1,5-Substituted Hydantoins Using Cyanobenziodoxolone

A method for the synthesis of enantiopure 1,5-substituted hydantoins was developed using a hypervalent iodine cyanation reagent (cyanobenziodoxolone, CBX) as a source of electrophilic carbon. Starting from inexpensive commercially available enantiopure protected amino acids, the method allowed the synthesis of various hydantoins without epimerization. Formation of hydantoins from dipeptides was also possible, but partial epimerization was observed in this case. This synthetic strategy is user friendly as CBX is a bench-stable easy-to-handle crystalline reagent and avoids conventional multistep protocols, thus allowing the facile synthesis of a library of chiral hydantoins.

Recent Advances in the Synthesis of Hydantoins: The State of the Art of a Valuable Scaffold

The review highlights the hydantoin syntheses presented from the point of view of the preparation methods. Novel synthetic routes to various hydantoin structures, the advances brought to the classical methods in the aim of producing more sustainable and environmentally friendly procedures for the preparation of these biomolecules, and a critical comparison of the different synthetic approaches developed in the last twelve years are also described. The review is composed of 95 schemes, 8 figures and 528 references for the last 12 years and includes the description of the hydantoin-based marketed drugs and clinical candidates.

(+)-trans-Chlorido-{2-[(Rp)-2-(methyl-sulfan-yl)ferro-cen-yl]-2,5,6,7-tetra-hydro-pyrrolo-[1,2-c]imidazol-3-yl-idene}bis(tri-phenyl-phosphane-κP)palladium(II) hexa-fluorido-phosphate di-chloro-form disolvate

The title solvated complex, [FePd(C5H5)(C12H13N2S)Cl(C18H15P)2]PF6·2CHCl3, bearing a chiral ferrocenyl pyrrolo-imidazolyl-idene N-heterocyclic carbene (NHC) ligand, was synthesized by oxidative addition of a chloro-imidazolium salt to Pd(PPh3)4. The PdII ion is coordinated in a slightly distorted square-planar coordination geometry, with the Cl atom trans to the coordinating C atom of the pyrrolo-imidazolyl-idene ligand. The complex features a pendant thio-ether group that is not involved in coordination to Pd. In the crystal, weak C-H⋯F and C-H⋯π inter-actions connect the components of the structure, forming chains propagating along [1-10]. The fused pyrrolidine ring is in an envelope conformation, and the flap atom was refined as disordered over two sets of sites, with occupancies of 0.77 (4) and 0.23 (4).