A Combined Spectroscopic and Computational Study on the Mechanism of Iron-Catalyzed Aminofunctionalization of Olefins Using Hydroxylamine Derived N–O Reagent as the “Amino” Source and “Oxidant”

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(6), P. 2637 - 2656

Published: Feb. 4, 2022

Herein, we study the mechanism of iron-catalyzed direct synthesis unprotected aminoethers from olefins by a hydroxyl amine derived reagent using wide range analytical and spectroscopic techniques (Mössbauer, Electron Paramagnetic Resonance, Ultra-Violet Visible Spectroscopy, X-ray Absorption, Nuclear Resonance Vibrational resonance Raman) along with high-level quantum chemical calculations. The triflic acid salt acts as "oxidant" well "amino" group donor. It activates high-spin Fe(II) (St = 2) catalyst [Fe(acac)2(H2O)2] (1) to generate 5/2) intermediate (Int I), which decays second II) St 2. analysis computational data leads formulation Int I [Fe(III)(acac)2-N-acyloxy] (an alkyl-peroxo-Fe(III) analogue). Furthermore, II is formed N–O bond homolysis. However, it does not high-valent Fe(IV)(NH) species (a Fe(IV)(O) analogue), but instead Fe(III) center strongly antiferromagnetically coupled (J −524 cm–1) an iminyl radical, [Fe(III)(acac)2-NH·], giving Though Fe(NH) complexes isoelectronic surrogates Fe(O) functionalities are known, detection Fe(III)-N-acyloxy undergoes cleavage active iron–nitrogen II), unprecedented. Relative centers, features weak elongated Fe–N which, together unpaired electron density vector, helps rationalize its propensity for N-transfer reactions onto styrenyl olefins, resulting in overall formation aminoethers. This thus demonstrates potential utilizing iron-coordinated nitrogen-centered radicals powerful reactive intermediates catalysis.

Language: Английский

---

Boc Protection for Diamine-Appended MOF Adsorbents to Enhance CO₂ Recyclability under Realistic Humid Conditions

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 146(1), P. 646 - 659

Published: Dec. 27, 2023

Among the various metal–organic framework (MOF) adsorbents, diamine-functionalized Mg2(dobpdc) (dobpdc4– = 4,4-dioxidobiphenyl-3,3′-dicarboxylate) shows remarkable carbon dioxide removal performance. However, applying in practical applications is premature because it persistent performance degradation under real flue gas conditions containing water vapor owing to diamine loss during wet cycles. To address this issue, we employed hydrophobic carbonate compounds protect groups een-Mg2(dobpdc) (een-MOF, een N-ethylethylenediamine). tert-Butyl dicarbonate (Boc) reacted rapidly with diamines at pore openings of MOF particles form dense secondary and tertiary amines, effectively preventing moisture ingress. The Boc-protected een-MOF-Boc1 maintained excellent CO2 adsorption even simulated 10% H2O. This observation indicates that Boc protection renders intact repeated cycles, suggesting are resistant replacement by molecules. increase practicability adsorbent, fabricated een-MOF/PAN-Boc1 composite beads shaping polyacrylonitrile (PAN). Notably, their after repeating temperature swing process more than 150 times vapor. Furthermore, breakthrough tests showed dynamic separation was retained humid conditions. These results demonstrate provides an easy effective way develop promising adsorbents high capacity, long-term durability, properties required for postcombustion applications.

Language: Английский

---

The Discovery of GSK3640254, a Next-Generation Inhibitor of HIV-1 Maturation

Journal of Medicinal Chemistry, Journal Year: 2022, Volume and Issue: 65(18), P. 11927 - 11948

Published: Aug. 31, 2022

GSK3640254 is an HIV-1 maturation inhibitor (MI) that exhibits significantly improved antiviral activity toward a range of clinically relevant polymorphic variants with reduced sensitivity the second-generation MI GSK3532795 (BMS-955176). The key structural difference between and its predecessor replacement para-substituted benzoic acid moiety attached at C-3 position triterpenoid core cyclohex-3-ene-1-carboxylic substituted CH2F carbon atom α- to pharmacophoric carboxylic acid. This element provided new vector which explore structure-activity relationships (SARs) led compounds coverage while preserving pharmacokinetic (PK) properties. approach design GSK3640254, development synthetic route preclinical profile are discussed. currently in phase IIb clinical trials after demonstrating dose-related reduction viral load over 7-10 days dosing HIV-1-infected subjects.

Language: Английский

---

Maneuvering the Bioactivities using Functionalized Biginelli Dihydropyrimidinone Amine Derivatives: Zebrafish Model System Tagged Biotoxicity is No Longer 'Fishy'

Journal of Molecular Structure, Journal Year: 2025, Volume and Issue: unknown, P. 142049 - 142049

Published: March 1, 2025

Language: Английский

---

Thermoreversible Transformations of the Cyanosubstituted 2‐Oxopyrrole Derivative by the Action of Amines for the Creation of Novel High‐Contrast Coloration/Decoloration Systems

ChemistrySelect, Journal Year: 2024, Volume and Issue: 9(11)

Published: March 15, 2024

Abstract A new efficient approach to the synthesis of intensely colored 2‐(2‐oxo‐3 H ‐pyrrol‐3‐ylidene)malononitrile ( OP ) was developed. Using reaction with amines, a series previously unknown colorless organic salts – dicyano(2‐oxo‐2,5‐dihydro‐1 ‐pyrrol‐3‐yl)methanides were synthesized, bearing in structure two fragments same or diverse amines different nature (covalent and ionic). TGA‐DTA study synthesized showed thermal reversibility their formation. The introduction violet into paper followed by treatment amine vapors revealed prospects using such system for naked‐eye detection volatile amines. It also shown that ‐based rewritable can be created, which data applied local heating erased action temperature.

Language: Английский

---

Mild Method for Deprotection of the N-Benzyloxycarbonyl (N-Cbz) Group by the Combination of AlCl₃ and HFIP

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(8), P. 5665 - 5674

Published: April 4, 2024

Herein, we report our findings on the novel ability of aluminum chloride (AlCl3) in fluorinated solvent 1,1,1,3,3,3-hexafluoroisopropanol [HFIP] to selectively deprotect N-benzyloxycarbonyl group (N-Cbz). The salient features this method are good functional tolerance including other reducible groups, cost-effectiveness, easy-to-handle, safe protocol, amenable scale-up, high yields, and ambient temperature reactions. methodology would serve as an excellent alternative use pyrophoric hydrogen gas metal catalyst reagents that pose severe safety environmental concerns. most notable feature is orthogonal deprotection N-Cbz presence O- N-Bn protecting hence, expanding scope for designing synthetic routes target compounds requiring multiple transformations.

Language: Английский

---

Selective Thermal Deprotection of N-Boc Protected Amines in Continuous Flow

Organic Process Research & Development, Journal Year: 2024, Volume and Issue: 28(5), P. 1946 - 1963

Published: April 25, 2024

Thermal N-Boc deprotection of a range amines is readily effected in continuous flow, the absence an acid catalyst. While optimum results were obtained methanol or trifluoroethanol, can be solvents different polarities. Sequential selective groups has been demonstrated through temperature control, as exemplified by effective removal aryl group presence alkyl group. As proof principle, telescoped sequence involving from 9h followed benzoylation and remaining to form amide 13 proved successful.

Language: Английский

---

Ligand-Enabled Carboamidation of Unactivated Alkenes through Enhanced Organonickel Electrophilicity

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(46), P. 25293 - 25303

Published: Nov. 8, 2023

Catalytic carboamination of alkenes is a powerful synthetic tool to access valuable amine scaffolds from abundant and readily available alkenes. Although number approaches have been developed achieve the rapid buildup molecular complexity in this realm, installation diverse carbon nitrogen functionalities onto unactivated remains underdeveloped. Here we present ligand design approach enable nickel-catalyzed three-component carboamidation that applicable wide range alkenyl derivatives via tandem process involving alkyl migratory insertion inner-sphere metal-nitrenoid transfer. With method, various can be installed into both internal terminal alkenes, leading differentially substituted diamines would otherwise difficult access. Mechanistic investigations reveal tailored Ni(cod)(BQiPr) precatalyst modulates electronic properties presumed π-alkene-nickel intermediate quinone ligand, enhanced carbonickelation efficiency across C═C bond. These findings establish nickel's ability catalyze multicomponent with high exquisite selectivity.

Language: Английский

---

Cu-Catalysed sustainable synthesis of formamide with glycerol derivatives as a carbonyl source via a radical-relay mechanism

Green Chemistry, Journal Year: 2023, Volume and Issue: 25(4), P. 1464 - 1472

Published: Jan. 1, 2023

N -Formylation of amines to formamides was achieved at a low temperature by total utilization the carbon atoms glycerol derivatives as C 1 feedstock over CuZr/5A via ˙OH–˙OOH radical mechanism.

Language: Английский

---

La-Catalyzed Decarbonylation of Formamides and Its Applications

Organic Letters, Journal Year: 2022, Volume and Issue: 25(1), P. 163 - 168

Published: Dec. 25, 2022

Herein we report the first catalytic decarbonylation and decarbonylative hydroamination of formamides without using additives enabled by a redox-neutral rare earth catalyst. The protocol displays complete N-aryl/alkenyl formamide-selectivity, thus providing wide variety creative uses N-formylation N-deformylation method opening up new prospects for minimizing waste controlling required selectivity in amine transformation events.

Language: Английский

---