Organic & Biomolecular Chemistry最新文献

Sulfilimines were exploited as valuable moieties in organic synthesis and medicinal chemistry; however, efficient methods for constructing such scaffolds remain limited. Herein, we disclosed a convenient method for modular synthesis of structurally diverse sulfilimines through NFSI-mediated oxidative S-arylation of sulfenamides with naphthols, phenols and indoles at room temperature. This straightforward process proceeded smoothly under mild conditions, with a broad substrate scope and high overall efficiency. The potential synthetic merit of this protocol was further demonstrated through gram-scale reactions, product derivatization and late-stage modification of natural products and drugs.

Hydroquinones can be used as precursors to synthesise a variety of bioactive molecules. Although many researchers have developed synthesis methods for hydroquinones, several drawbacks, such as poor environmental friendliness, low atom efficiency, high cost, and potential toxicity, remain unresolved. Therefore, the development of more environmentally friendly, atom-efficient, and cheaper alternatives is becoming increasingly important. In this paper, we report a general method for the synthesis of hydroquinones using cheap metal-based pre-catalysts, namely (cyclopentadienone)iron complexes (CICs). CICs catalyse the 1,4-reduction of quinones to give a range of hydroquinones in high yields (up to 99%) and present a good substrate scope. Furthermore, the practicality of the synthetic methodology was also evaluated, and good results were obtained.

The copper-catalyzed insertion of α-furyl boryl carbenes generated from BMIDA-terminated enynones into the B-H bond of Lewis base-borane adducts offers facile and atom-economical access to gem-diborylalkanes. This protocol proceeds in moderate to excellent yields (up to 95%) under mild conditions. Moreover, the boryl group derived from Lewis base-borane adducts can be selectively transformed into a diverse array of borate groups, which together with the large-scale experiment illustrates the synthetic potential of this methodology.

Organogermanium compounds are widely used in organic synthesis, medicinal chemistry, and materials science, attracting significant attention from organic chemists. As a result, the development of novel and efficient synthetic methods for organogermanium compounds has garnered significant attention. In recent years, radical reactions have emerged as an important strategy for the synthesis of organogermanium compounds, owing to their mild conditions, good functional-group tolerance, and operational simplicity. Among these, germyl hydride (Ge-H) compounds serve as crucial precursors for germanium-centered radicals. This review summarizes the latest advances in the synthesis of organogermanium compounds using Ge-centered radicals generated from Ge-H bonds, providing a foundation for developing novel approaches.

The incorporation of a sulfoximine group into parent molecules is of interest. In this work, we report a practical and efficient alkyldisulfanium salt-mediated α-sulfoximidation of alkenes with NH-sulfoximines. This method enables the synthesis of various thioether group-containing alkyl sulfoximines in moderate to good yields. Mild and catalyst-free conditions, readily available substrates and operational simplicity make this method quite attractive in organic synthesis.

We report herein a one-step three-component decarboxylative strategy for the construction of novel azatrithiapentalenes from readily available cinnamonitriles, arylacetic acids and elemental sulfur. The reaction was found to proceed in DMSO in the presence of DABCO as a basic promoter through an unusual disproportionate incorporation of three sulfur atoms into the carbon skeletons derived from two organic substrates. A comprehensive examination of the substrate scope demonstrated that the reaction conditions are broadly tolerant, including substrates bearing a diverse array of substituents with markedly different electronic and steric features. Control experiments demonstrated that elemental sulfur reacts independently with both starting organic substrates to yield two key intermediates that could combine together to yield azatrithiapentalenes. The reaction could be extended to phenylmethanethiols or dibenzyl disulfides in place of phenylacetic acids.

The replacement of N,N-dimethylformamide (DMF) in solid-phase peptide synthesis (SPPS) is critical for improving the sustainability and safety of peptide research. While N-butyl-2-pyrrolidinone (NBP) has emerged as a viable alternative for linear peptide synthesis, its applicability to post-linear synthesis modifications remains underexplored. Here, we demonstrate the use of NBP as an alternative solvent for key on-resin transformations required in peptidomimetic synthesis. Orthogonal protecting group strategies were successfully implemented, enabling selective removal of Cys(SIT), Cys(Acm), Cys(Trt), and Lys(Dde) under mild conditions. Notably, SIT deprotection achieved 92% conversion in a single 4-hour treatment, while Acm and Trt were selectively removed using iodine or N-halosuccinimides, respectively. Lys(Dde) was efficiently cleaved in the presence of Cys(Acm) using 4% hydrazine in NBP. Furthermore, on-resin cyclisation via disulfide bond and 1,4-disubstituted triazole formation proceeded effectively in NBP, as did N-terminal acetylation under mild conditions. These findings establish NBP as a practical and greener alternative to DMF for diverse post-linear synthesis modifications, supporting the development of sustainable SPPS protocols.

A copper-catalyzed multicomponent radical domino reaction of 1-allyl-2-ethynylbenzoimidazoles with Togni's reagent, amines and CO₂ was successfully developed. This method provides a convenient and efficient approach to access valuable trifluoromethyl- and carbamoyloxyl-substituted ring-fused benzimidazoles in satisfactory yields with good functional group tolerance and high regio- and stereo-selectivity. Additionally, it enables the conversion and utilization of CO₂ under mild conditions.

Herein, we report a new methodology for the electrochemical oxidative C-H trifluoromethylation of 4-phenylthiazol-2-amines in an undivided cell using a glassy carbon electrode (GCE) and sodium trifluoromethanesulfinate (CF₃SO₂Na; Langlois' reagent) as the CF₃ radical source. Using this tert-butyl hydroperoxide (TBHP)-mediated and transition metal-free effective approach, trifluo-romethylated 4-phenylthiazol-2-amines were synthesized in high yields (up to 97%).

The construction of spiro-iminoindoline-pyrazolines from readily available starting materials has garnered significant interest within the synthetic chemistry community. Herein, we report a chemo- and diastereoselective (2 + 3) and three-component formal (1 + 1 + 3) cascade cyclization strategy for their synthesis, demonstrating unprecedented CC chemoselectivity of nitrile imines toward α,β-unsaturated imines. This method delivers multifunctionalized products efficiently under mild conditions. Furthermore, preliminary antioxidant screening using the DPPH radical scavenging assay highlights their potential bioactivity.