Unifying Metal- and Organocatalysis for Asymmetric Oxidative Iminium Activation: A Relay Catalytic System Enabling the Combined Allylic Oxidation of Alcohols and Prolinol Ether Catalyzed Iminium Reactions

Metal-free β,γ-C(sp3)-H difunctionalization of propanols: DMP-initiated asymmetric spirocyclopropanation

A DMP-initiated metal-free effective β,γ-asymmetric spirocyclopropanation of propanols strategy using oxidative iminium activation is described. This process has been realized by a synergistic amine-catalyzed one-pot cascade oxidation-Michael addition cyclopropanation for "one-pot" access to various spirocyclopropyl propionaldehydes/propanols from diverse 3-arylpropanols and α-brominated active methylene compounds under mild conditions and with high enantioselectivity (ee up to >99%).

Organocatalytic Reductive Amination of the Chiral Formylcyclopropanes: Scope and Applications

We developed a sustainable three-component reductive amination protocol for the chemoselective coupling of optically active functionally rich donor-acceptor carbonyl-cyclopropanes with various amines under 10 mol % of diphenyl phosphate in the presence of Hantzsch ester as a hydride source. The catalytic selective reductive C-N coupling has wide advantages like no epimerization, no ring opening, large substrate scope, generating only mono N-alkylation products and simultaneously resulting in chiral cyclopropane-containing amines possessing many applications in the medicinal chemistry. In this article, we have shown the synthetic applications of reductive C-N coupling reaction to make chiral α-carbonyl-cyclopropane containing amines 8, double C-N coupled cyclopropane-amines 10, unusual C-N/C-C coupled cyclopropane-amines 12, chiral tert-butylsulfinamide containing cyclopropanes 14/15, and functionally rich chiral cyclopropane-fused N-heterocycles 16/18/19. Many of these chiral cyclopropane-amines 5-19 can serve as building blocks for the synthesis of drug-like small molecules, natural products, pharmaceuticals, and their analogues.

Unconventional Gold-Catalyzed One-Pot/Multicomponent Synthesis of Propargylamines Starting from Benzyl Alcohols

A formal homogeneous gold-catalyzed A3-coupling, starting from benzyl alcohols, is reported for the straightforward synthesis of propargylamines. This is the first process where these highly valuable compounds have been synthesized, starting from the corresponding alcohols in a one-pot oxidation procedure using MnO2, followed by a HAuCl4·3H2O catalyzed multicomponent reaction. The final products are obtained with very good yields in short reaction times, which is of fundamental interest for the synthesis of pharmaceuticals. The usefulness and efficiency of our methodology is successfully compared against the same reaction starting from aldehydes.

A new chiral dimanganese(iii) complex: synthesis, crystal structure, spectroscopic, magnetic, and catalytic properties

The two enantiomeric dimanganese(iii) complexes are efficient catalysts, with a total enantioselectivity, in the epoxidation of methyl trans-cinnamate.

Fluorine effects in organocatalysis - asymmetric Brønsted acid assisted Lewis base catalysis for the synthesis of trifluoromethylated heterocycles exploiting the negative hyperconjugation of the CF3-group

An efficient Brønsted acid assisted Lewis base catalysis protocol for the synthesis of enantiomerically pure trifluoromethylated dihydropyridazines starting from readily available hydrazones and α,β-unsaturated aldehydes has been developed. The reaction exhibits high tolerance towards many functional groups and is applicable to various aliphatic, aromatic and hetero-aromatic α,β-unsaturated aldehydes, and provides the products in good yields and with excellent enantioselectivities.

Dual metal and Lewis base catalysis approach for asymmetric synthesis of dihydroquinolines and the α-arylation of aldehydes via N-acyliminium ions

A dual catalytic system consisting of indium triflate and a chiral imidazolidinone catalyzes the asymmetric addition of aldehydes to N-acyl quinoliniums furnishing optically active dihydroquinolines in good yields and excellent selectivities.