Synthesis of Secondary Aromatic Amides via Pd-Catalyzed Aminocarbonylation of Aryl Halides Using Carbamoylsilane as an Amide Source

Using <i>N</i>-methoxymethyl-<i>N</i>-organylcarbamoyl­(trimethyl)­silanes as secondary amides source, the direct transformation of aryl halides into the corresponding secondary aromatic amides via palladium-catalyzed aminocarbonylation is described. The reactions tolerated a broad range of functional groups on the aryl ring except big steric hindrance of substituent. The types and the relative position of substituents on the aryl ring impact the coupling efficiency

Polycyclic Azetidines and Pyrrolidines via Palladium-Catalyzed Intramolecular Amination of Unactivated C(sp3)–H Bonds

A novel strategy to construct complex polycyclic nitrogen-containing heterocycles from aliphatic amines via picolinamide-assisted palladium-catalyzed C–H bond activation reaction was reported. The reaction exhibits broad substrate scope for the synthesis of various azabicyclic scaffolds, including azetidines and tropane-class alkaloids. Application of this method to naturally occurring (−)-<i>cis</i>-myrtanylamine, an unprecedented type of carbon–carbon bond activation, in which the electron-pair involved initiates an intramolecular “S_N2-like” displacement of a cyclopalladium-fragment from a tertiary center, is described

Polycyclic Azetidines and Pyrrolidines via Palladium-Catalyzed Intramolecular Amination of Unactivated C(sp3)–H Bonds

A novel strategy to construct complex polycyclic nitrogen-containing heterocycles from aliphatic amines via picolinamide-assisted palladium-catalyzed C–H bond activation reaction was reported. The reaction exhibits broad substrate scope for the synthesis of various azabicyclic scaffolds, including azetidines and tropane-class alkaloids. Application of this method to naturally occurring (−)-<i>cis</i>-myrtanylamine, an unprecedented type of carbon–carbon bond activation, in which the electron-pair involved initiates an intramolecular “S_N2-like” displacement of a cyclopalladium-fragment from a tertiary center, is described

Additional file 1: of Estimated assessment of cumulative dietary exposure to organophosphorus residues from tea infusion in China

Table S1. BMD at 10% AChE inhibition in female rat brain of OPs found in tea samples from the China monitoring programs. Table S2. CED at 20% AChE inhibition in female rat brain of OPs found in tea samples from the China monitoring programs. Table S3. TRs of OP residues to tea infusion. Table S4. Water solubility and octanol-water partition coefficient of OPs. (DOCX 28 kb

Palladium-Catalyzed Unactivated C(sp³)–H Bond Activation and Intramolecular Amination of Carboxamides: A New Approach to β‑Lactams

An efficient method to synthesize the β-lactams with high regioselectivity via Pd-catalyzed C­(sp³)–H bond activation and intramolecular amination of simple and readily available aminoquinoline carboxamides was demonstrated. C₆F₅I plays a significant role in the formation of the C–N bond of the four-membered ring β-lactams. High yield along with wide substrate scope and functional group tolerance makes this reaction applicable to build natural-product-derived β-lactams. This method has been applied to the efficient synthesis of the β-lactamase inhibitor MK-8712

Novel Dispersive Micro-Solid-Phase Extraction Combined with Ultrahigh-Performance Liquid Chromatography–High-Resolution Mass Spectrometry To Determine Morpholine Residues in Citrus and Apples

This paper presents a new analytical method for the determination of morpholine residues in citrus and apples using a novel dispersive micro-solid-phase extraction (DMSPE), followed by ultrahigh-performance liquid chromatography–high-resolution mass spectrometry (UHPLC–HRMS). Samples were extracted with 1% formic acid in acetonitrile/water (1:1, v/v) and then cleaned up using the DMSPE procedure. Morpholine from the extract was adsorbed to a polymer cation exchange sorbent and eluted with ammonium hydroxide/acetonitrile (3:97, v/v) through a 1 mL syringe with a 0.22 μm nylon syringe filter. All of the samples were analyzed by UHPLC–HRMS/MS on a Waters Acquity BEH hydrophilic interaction chromatography column using 0.1% formic acid and 4 mM ammonium formate in water/acetonitrile as the mobile phase with gradient elution. The method showed good linearity (<i>R</i>² > 0.999) in the range of 1–100 μg/L for the analyte. The limit of detection and limit of quantitation values of morpholine were 2 and 5 μg/kg, respectively. The average recoveries of morpholine from the citrus and apple samples spiked at three different concentrations (5, 20, and 100 μg/kg) were in a range from 78.4 to 102.7%

Palladium-Catalyzed Unactivated C(sp³)–H Bond Activation and Intramolecular Amination of Carboxamides: A New Approach to β‑Lactams

An efficient method to synthesize the β-lactams with high regioselectivity via Pd-catalyzed C­(sp³)–H bond activation and intramolecular amination of simple and readily available aminoquinoline carboxamides was demonstrated. C₆F₅I plays a significant role in the formation of the C–N bond of the four-membered ring β-lactams. High yield along with wide substrate scope and functional group tolerance makes this reaction applicable to build natural-product-derived β-lactams. This method has been applied to the efficient synthesis of the β-lactamase inhibitor MK-8712

Palladium-Catalyzed Unactivated C(sp³)–H Bond Activation and Intramolecular Amination of Carboxamides: A New Approach to β‑Lactams

An efficient method to synthesize the β-lactams with high regioselectivity via Pd-catalyzed C­(sp³)–H bond activation and intramolecular amination of simple and readily available aminoquinoline carboxamides was demonstrated. C₆F₅I plays a significant role in the formation of the C–N bond of the four-membered ring β-lactams. High yield along with wide substrate scope and functional group tolerance makes this reaction applicable to build natural-product-derived β-lactams. This method has been applied to the efficient synthesis of the β-lactamase inhibitor MK-8712

Palladium-Catalyzed Unactivated C(sp³)–H Bond Activation and Intramolecular Amination of Carboxamides: A New Approach to β‑Lactams

An efficient method to synthesize the β-lactams with high regioselectivity via Pd-catalyzed C­(sp³)–H bond activation and intramolecular amination of simple and readily available aminoquinoline carboxamides was demonstrated. C₆F₅I plays a significant role in the formation of the C–N bond of the four-membered ring β-lactams. High yield along with wide substrate scope and functional group tolerance makes this reaction applicable to build natural-product-derived β-lactams. This method has been applied to the efficient synthesis of the β-lactamase inhibitor MK-8712

Stereoselective Synthesis of Diazabicyclic β‑Lactams through Intramolecular Amination of Unactivated C(sp³)–H Bonds of Carboxamides by Palladium Catalysis

An efficient C­(sp³)–H bond activation and intramolecular amination reaction via palladium catalysis at the β-position of carboxyamides to make β-lactams was described. The investigation of the substrate scope showed that the current reaction conditions favored activation of the β-methylene group. Short sequences were developed for preparation of various diazabicyclic β-lactam compounds with this method as the key step from chiral proline and piperidine derivatives