A 2,2‐Difluoroimidazolidine Derivative for Deoxyfluorination Reactions: Mechanistic Insights by Experimental and Computational Studies

Chemistry - A European Journal, Год журнала: 2023, Номер 29(58)

Опубликована: Июнь 21, 2023

A N-heterocyclic deoxyfluorinating agent SIMesF2 was synthesized by nucleophilic fluorination of N,N-1,3-dimesityl-2-chloroimidazolidinium chloride (3) at room temperature. applied to deoxyfluorinate carboxylic acids and alcohols convert benzaldehyde into difluorotoluene. Mechanistic studies NMR spectroscopy suggest reaction pathways the acid acyl fluoride via outer-sphere fluorinations an imidazolidinium ion polyfluoride. DFT give further insight exploring mechanistic details which distinguish aldehydes from that acids. Furthermore, a consecutive sequence for oxidation aldehyde followed in situ generated developed.

Язык: Английский

---

Synthesis of Amides and Peptides by Employing [4-(Acetylamino) phenyl]imidodisulfuryl Difluoride (AISF) as a Coupling Reagent

Synthesis, Год журнала: 2024, Номер 56(09), С. 1476 - 1484

Опубликована: Фев. 8, 2024

Abstract A new synthetic approach for the preparation of amides and peptides containing amino acids as well aryl amines by employing [4-(acetylamino)phenyl]imidodisulfuryl difluoride (AISF) a carboxylic acid activator under mild conditions is delineated. The use AISF an allows reaction to be performed efficiently. This operationally simple amidation amenable wide variety Nα-protected acids. Further, racemization did not occur during coupling. In addition, gram-scale demonstrated.

Язык: Английский

---

20.8.13 Thiocarboxylic S-Acid, Selenocarboxylic Se-Acid, and Tellurocarboxylic Te-Acid Derivatives (Update 2024)

Опубликована: Янв. 1, 2024

Abstract Thiocarboxylic acid S-esters are synthetically versatile building blocks that can be smoothly interconverted into a wide array of valuable functional groups including aldehydes, ketones, carboxylic acids, and amides. This review, which is an update to earlier Science Synthesis contribution (Section 20.8), covers synthetic strategies access thiocarboxylic other derivatives, primarily focuses on the literature published between 2006 2023. Additionally, robust methods prepare seleno- tellurocarboxylic esters, becoming widely used synthons in total synthesis peptide chemistry, highlighted.

Язык: Английский

---

20.5.1.2.9 Synthesis of Esters from Carboxylic Acids and Derivatives (Update 2024)

Опубликована: Янв. 1, 2024

Abstract This review is a further update to the earlier Science of Synthesis contributions detailing preparation carboxylic acid esters from corresponding acids and other derivatives [Sections 20.5.1.2 (2007) 20.5.1.2.8 (2011)], considers relevant esterification methods that were not covered in those previous chapters or have been reported since then. Protocols for synthesis alcohols, alkyl halides (and surrogates), alkenes, allenes are included. Moreover, ester formation through C(sp3)—H functionalization derivatives, such as N-acyloxazolidinones amides, also covered.

Язык: Английский

---

Thionyl Fluoride

Encyclopedia of Reagents for Organic Synthesis, Год журнала: 2024, Номер unknown, С. 1 - 2

Опубликована: Ноя. 30, 2024

image [7783‐42‐8] SOF 2 (MW 86.061) InChI = 1S/F2OS/c1‐4(2)3 InChIKey LSJNBGSOIVSBBR‐UHFFFAOYSA‐N (reagent used for fluorination, nucleophilic acyl substitutions including one‐pot peptide coupling and introduction of S(O)F group) Alternative Names: sulfinyl fluoride, sulfur difluoride oxide, monoxide, sulfurous oxyfluoride, thionyl difluoride. Physical Data: mp −129.5 °C, bp −43.8 d 1.758 g cm −3 . Solubility: soluble in ethanol, ether, benzene. Hydrolyzes water. Form Supplied in: colorless gas packaged cylinders, commercially available. Analysis Reagent Purity: singlet 19 F NMR at δ −72.2. 1,2 IR (cm −l ) 1333, 808, 748, 530, 410, 390. 3 Preparative Methods: fluoride is typically generated from chloride a salt followed by condensation the resulting gas. 4 More conveniently, it can be ex situ, bubbled various organic solvents, directly or kept as stock solution. 5 It also one major decomposition products hexafluoride under electric discharges, hydrolysis tetrafluoride air. 6 Purification: fractionated distillation through low‐temperature column. Handling, Storage, Precautions: toxic that should handled well‐ventilated fume hood.

Язык: Английский

---

1.1 Sulfonyl Fluorides and Acyl Fluorides

Опубликована: Янв. 1, 2024

Abstract Sulfonyl fluorides have numerous applications in both synthetic organic chemistry as fluorinating agents and precursors to sulfur(VI) moieties, chemical biology covalent inhibitors probes. The utility of sulfonyl arises from the properties S—F bond, high bond strength polarization imparts stability chemoselectivity that differentiates this group other halides. Likewise, acyl found widespread use synthesis reactive intermediates. increased toward hydrolysis aminolysis comparison chlorides bromides are a result relative electrostatic C—F bond. In review, we provide an overview approaches these valuable motifs, with focus on versatile easy-to-handle protocols.

Язык: Английский

---

Computational study of the atmospheric oxidation and global warming potential of thionyl fluoride

International Journal of Quantum Chemistry, Год журнала: 2023, Номер 123(13)

Опубликована: Март 2, 2023

Abstract Thionyl fluoride (SOF 2 ) is the dominant decomposition by‐product in SF 6 under electrical discharges and a novel fluorinating reagent for organic synthesis to replace sulfuryl (SO F ). Since both SO are strong green‐house gases, sake of environmental concern, tropospheric oxidation SOF by OH radicals presence O has been investigated using various computational methods including density functional M06‐2X, coupled‐cluster (CCSD), explicitly correlated RCCSD(T)‐F12, Gaussian‐4, ROCBS‐QB3, Weizmann‐1 theories. The SO bond association between proceeds via barriers 1–3 kcal/mol form shallow wells HOSOF (−3 −8 kcal/mol) linked Berry pseudorotations followed HF‐elimination. Interception adducts produce HO predominantly concerted association/dissociation proton‐transfer. atmospheric lifetime radiative efficiency were calculated be 1.2–1.5 years 0.223 W/m /ppb, respectively. global warming potential was estimated 169–211, as indicative an eco‐friendly gas. However, impact should take into account production due oxidation.

Язык: Английский

---

Peptide Bond Formation Mediated by Thionyl Fluoride

Synfacts, Год журнала: 2022, Номер 18(08), С. 0931 - 0931

Опубликована: Июль 18, 2022

Key words thionyl fluoride - one-pot reaction carboxylic acids peptide bond amidation

Язык: Английский

---