The chromanone scaffold is a privileged structure in heterocyclic chemistry and drug discovery. A highly efficient copper-catalyzed asymmetric conjugated reduction of chromones is developed to give chiral chromanones with good yields (80–99%) and excellent ee values (94–>99% ee). Particularly noteworthy is that chiral thiochromanones are also constructed using this method in 74–87% yields with 96–97% ee. The established asymmetric synthesis paves the way for their further pharmaceutical studies.

A highly efficient asymmetric synthesis of chiral thioflavanones is developed via conjugate addition of arylzinc reagents to thiochromones using Rh(COD)Cl2/(R)-3,4,5-MeO-MeOBIPHEP catalyst. This method overcomes catalyst poisoning and substrate inertness and affords a series of chiral thioflavanones (2-arylthiochroman-4-ones) in good yields (up to 91% yield) with excellent ee values (up to 97% ee). The established asymmetric synthesis paves the way for further pharmaceutical studies.

A highly efficient asymmetric ring addition reaction of oxabenzonorbornadienes with thiophenols using an iridium/(S)-xyl-binap catalyst is developed. This catalyst system overcomes catalyst poisoning and background reactions and allows the formation of exclusive thiol addition products in high yields (up to 97% yield) with excellent enantioselectivities (up to 98% ee). Particularly noteworthy is that no competitive ring-opened side products are observed. X-ray crystal structure analysis confirmed the adduct is solely in the exo-configuration.

•Three-component cyclization was developed to give 1,4-dihydropyridines.•This practical protocol could proceed in gram scale with 1 mol % catalytic loading.•Control experiments were studied and possible mechanism was proposed.A copper(II) triflate-catalyzed three-component cyclization of alkynes, amines, and α,β-unsaturated aldehydes was developed to give various 1,4-dihydropyridines in good to high yields. In addition, this efficient and practical protocol proceeded smoothly in gram scale even when the catalytic loading was reduced to 1 mol %.

A novel difunctionalization reaction is described. It uses N-trifluoromethylthio-4-nitrophthalimide as the reagent, which serves as both the nitrogen and SCF3 sources. In the presence of DABCO (1,4-diazabicyclo[2.2.2]octane), the nitrogen and SCF3 groups can be incorporated into α,β-unsaturated carbonyl compounds easily and give versatile β-amino ketones and esters in good yields. This difunctionalization reaction features mild reaction conditions, high atom-economy, and efficient access to α-SCF3 amino acids.

A combination of iridium/copper associated with (R)-Difluorphos catalyst for the asymmetric ring opening reaction of azabenzonorbornadienes with amines was developed, which afforded chiral trans-vicinal diamines in 80–97% yields with 93–95% enantioselectivities.

Chiral cyclohex-2-enones are important building blocks in synthetic chemistry and the life science industries and much attention has been drawn to the development of efficient and practical methodologies for accessing these enantio-enriched cyclohex-2-enone skeletons. This review describes the impressive progress that has been made in terms of employing new methodologies, suitable reactants as well as more efficient catalyst systems for this important enantioselective transformation. Also, the reaction mechanisms are briefly discussed.

An efficient enantioselective aza-Michael addition of pyrazole to chalcone was established. In the presence of the primary amine derived from cinchona alkaloid and acidic additive, the reactions afforded 1,4-adducts in high yields (up to 98%) with 68–88% ee.1,3-Diphenyl-3-(1H-pyrazol-1-yl)propan-1-oneC18H16N2O[α]D20=+64.3 (c 1.00, CHCl3) 76% eeAbsolute configuration: not known1-Phenyl-3-(1H-pyrazol-1-yl)-3-p-tolylpropan-1-oneC19H18N2O[α]D20=+34.2 (c 1.00, CHCl3) 68% eeAbsolute configuration: not known3-(3-Bromophenyl)-1-phenyl-3-(1H-pyrazol-1-yl)propan-1-oneC18H15N2OBr[α]D20=+56.9 (c 1.00, CHCl3) 82% eeAbsolute configuration: not known1-(3-Methoxyphenyl)-3-phenyl-3-(1H-pyrazol-1-yl)propan-1-oneC19H18N2O2[α]D20=+66.5 (c 1.00 CHCl3) 77% eeAbsolute configuration: not known3-(4-Fluorophenyl)-1-phenyl-3-(1H-pyrazol-1-yl)propan-1-oneC18H15N2OF[α]D20=+58.2 (c 1.00, CHCl3) 72% eeAbsolute configuration: not known3-(4-(Trifluoromethyl)phenyl)-1-phenyl-3-(1H-pyrazol-1-yl)propan-1-oneC19H15N2OF3[α]D20=+60.2 (c 1.00, CHCl3) 84% eeAbsolute configuration: not known3-(4-Bromophenyl)-1-phenyl-3-(1H-pyrazol-1-yl)propan-1-oneC18H15N2OBr[α]D20=+36.0 (c 1.00, CHCl3) 83% eeAbsolute configuration: not known3-(3-Nitrophenyl)-1-phenyl-3-(1H-pyrazol-1-yl)propan-1-oneC18H15N3O3[α]D20=+27.9 (c 0.80, CHCl3) 80% eeAbsolute configuration: not known3-(4-Bromophenyl)-1-(3-chlorophenyl)-3-(1H-pyrazol-1-yl)propan-1-oneC18H14N2OClBr[α]D20=+27.8 (c 1.00, CHCl3) 76% eeAbsolute configuration: not known1-(4-Methoxyphenyl)-3-(1H-pyrazol-1-yl)-3-p-tolylpropan-1-oneC20H20N2O2[α]D20=+32.1 (c 1.00, CHCl3) 83% eeAbsolute configuration: not known3-(4-Methoxyphenyl)-1-phenyl-3-(1H-pyrazol-1-yl)propan-1-oneC19H18N2O2[α]D20=+12.5 (c 1.00, CHCl3) 30% eeAbsolute configuration: not known1-(3-Chlorophenyl)-3-phenyl-3-(1H-pyrazol-1-yl)propan-1-oneC18H15N2OCl[α]D20=+49.0 (c 1.00, CHCl3) 66% eeAbsolute configuration: not known3-(3,5-Dimethyl-1H-pyrazol-1-yl)-1,3-diphenylpropan-1-oneC20H20N2O[α]D20=+124.4 (c 1.00, CHCl3) 72% eeAbsolute configuration: not known

Chiral cyclohex-2-enones are important building blocks in synthetic chemistry and the life science industries and much attention has been drawn to the development of efficient and practical methodologies for accessing these enantio-enriched cyclohex-2-enone skeletons. This review describes the impressive progress that has been made in terms of employing new methodologies, suitable reactants as well as more efficient catalyst systems for this important enantioselective transformation. Also, the reaction mechanisms are briefly discussed.

The chromanone scaffold is a privileged structure in heterocyclic chemistry and drug discovery. A highly efficient copper-catalyzed asymmetric conjugated reduction of chromones is developed to give chiral chromanones with good yields (80–99%) and excellent ee values (94–>99% ee). Particularly noteworthy is that chiral thiochromanones are also constructed using this method in 74–87% yields with 96–97% ee. The established asymmetric synthesis paves the way for their further pharmaceutical studies.

Bismuth triflate (Bi(OTf)3) is identified as an efficient catalyst for the direct addition of isocyanides to 2H-chromene acetals. The large scope of isocyanides and chromene acetals makes them suitable substrates in this catalytic system. By this synthetic strategy, a polyfunctional molecular scaffold, 2-carboxamide-2H-chromenes could be prepared efficiently in one step up to 95% yield. In addition, this efficient and practical protocol proceeded smoothly in the gram scale even when the catalytic loading was reduced to 2 mol%.

A combination of iridium/copper associated with (R)-Difluorphos catalyst for the asymmetric ring opening reaction of azabenzonorbornadienes with amines was developed, which afforded chiral trans-vicinal diamines in 80–97% yields with 93–95% enantioselectivities.

The inexpensive Lewis acid AlCl3 was found to be an efficient catalyst for the O-alkylative Passerini reaction of isocyanides, cinnamaldehydes and alcohols. Instead of carboxylic acid in the classical Passerini reaction, alcohols performed both as the solvent and substrate nicely to afford α-alkoxy-amide products in good yield (up to 91%). This method provides practical access for functional α-alkoxy-β,γ-enamide derivatives.