Organocatalytic Enantioselective One-Pot Four-Component Ugi-Type Multicomponent Reaction for the Synthesis of Epoxy-tetrahydropyrrolo[3,4-

In the presence of a catalytic amount of chiral BINOL-derived phosphoric acid (TRIP), reaction of an α-isocyanoacetate 1, an aldehyde 2, an aniline 3 followed by addition of a toluene solution of α,β-unsaturated acyl chloride 5 afforded oxa-bridged tricycle 6 in excellent yield, diastereoselectivity and enantioselectivity. Six chemical bonds, five stereogenic centers, three cycles were formed in this one pot four-component reaction

Double-Oxidative Dehydrogenative (DOD) [4 + 2]-Cyclization/Oxidative Aromatization Tandem Reaction of Glycine Derivatives with Ethylbenzenes

The double-oxidative dehydrogenative (DOD) cyclization represents one of the most straightforward and atom-economical methods for cyclic structure formation. A Cu­(II)/DDQ/O₂ system-catalyzed DOD [4 + 2]-annulation/oxidative aromatization tandem reaction of readily available glycine derivatives and alkylbenzenes was established. This approach facilitates rapid access to a broad scope of substituted quinoline-2-carboxylate derivatives, an important motif in drug discovery. The reaction could feasibly be applied to a 10 gram-scale synthesis

Tin Powder-Promoted One-Pot Construction of α‑Methylene-γ-lactams and Spirolactams from Aldehydes or Ketones, Acylhydrazines, and 2‑(Bromomethyl)acrylate

A concise and efficient method for the synthesis of α-methylene-γ-lactams is developed from multicomponent one-pot reactions of aldehydes or ketones, hydrazides, and ethyl 2-(bromomethyl)­acrylate promoted by tin powder. The reaction proceeds smoothly under mild reaction conditions without using any catalyst to give the corresponding products in high yields. α-Methylene-<i>γ-</i>spirolactams can also be prepared from cyclic ketones

Synthesis of Benzimidazolones via One-Pot Reaction of Hydroxylamines, Aldehydes, and Trimethylsilyl Cyanide Promoted by Diacetoxyiodobenzene

A novel and efficient PhI­(OAc)₂-promoted one-pot reaction of aromatic hydroxylamines, aldehydes, and TMSCN in the presence of BF₃·Et₂O is described. A wide variety of <i>N</i>-substituted benzimidazolones are obtained with satisfactory yields under mild reaction conditions. The method was proven to be efficient for the synthesis of benzimidazolone derivatives from readily available starting materials

Stereodivergent Synthesis of Chromanones and Flavanones via Intramolecular Benzoin Reaction

The strategy of stereodivergent reactions on racemic mixtures (stereodivergent RRM) was employed for the first time in intramolecular benzoin reactions and led to the rapid access of chromanones/flavanones with two consecutive stereocenters. The easily separable stereoisomers of the products were obtained with moderate to excellent enantioselectivities in a single step. Catechol type additives proved crucial in achieving the desired diastereo- and enantioselectivities

Synthesis of Trifluoroethyl Pyrazolines via Trichloroisocyanuric Acid Promoted Cascade Cyclization/Trifluoromethylation of β,γ‑Unsaturated Hydrazones

A novel and efficient protocol for the construction of trifluoroethyl pyrazolines has been developed by cascade cyclization/­trifluoro­methyl­ation reaction of β,γ-unsaturated hydrazones. This strategy uses cheap and commercially available trichloroisocyanuric acid as promoter and TMSCF₃ as the trifluoromethylating reagent, which make the trifluoro­methyl­ating process much cheaper. A wide range of substrates can be applied in this process to afford the trifluoro­ethyl pyrazolines in good yield

Synthesis of Trifluoroethyl Pyrazolines via Trichloroisocyanuric Acid Promoted Cascade Cyclization/Trifluoromethylation of β,γ‑Unsaturated Hydrazones

A novel and efficient protocol for the construction of trifluoroethyl pyrazolines has been developed by cascade cyclization/­trifluoro­methyl­ation reaction of β,γ-unsaturated hydrazones. This strategy uses cheap and commercially available trichloroisocyanuric acid as promoter and TMSCF₃ as the trifluoromethylating reagent, which make the trifluoro­methyl­ating process much cheaper. A wide range of substrates can be applied in this process to afford the trifluoro­ethyl pyrazolines in good yield

Trichloroisocyanuric Acid Promoted Cascade Cyclization/Trifluoromethylation of Allylic Oximes: Synthesis of Trifluoromethylated Isoxazolines

Cheap and commercially available trichloroisocyanuric acid has been used to promote trifluoromethylation by using TMSCF₃ as the trifluoromethyl source. The method provides a novel and efficient protocol for the construction of CF₃-containing 4,5-dihydroisoxazoles from allylic oximes in good to excellent yields

Cascade Oxidation/Halogenoaminocyclization Reaction of Trifluoromethylated Homoallylic <i>N</i>‑Acylhydrazines: Metal-free Synthesis of CF₃‑Substituted Pyrazolines

An efficient and practical cascade oxidation/halogenoaminocyclization of trifluoromethylated homoallylic <i>N</i>-acylhydrazines is developed. The protocol enables an efficient access to various biologically interesting CF₃-containing pyrazoline compounds from readily accessible trifluoromethylated homoallylic <i>N</i>-acylhydrazines in good to excellent yields under mild conditions without any other additives or catalysts. The produced pyrazoline compounds can be further manipulated to other more complicated derivatives through transformation of residual halogen atom