Visible-Light-Induced Carbene Insertion into P–H Bonds between Acylsilanes and H-Phosphorus Oxides

Organic Letters, Journal Year: 2023, Volume and Issue: 25(13), P. 2338 - 2343

Published: March 28, 2023

An intriguing visible-light-induced strategy has been established for the P-H insertion reaction between acylsilanes and H-phosphorus oxides that, upon a subsequent acidic process, deliver wide variety of α-hydroxyphosphorus in good yields (up to 93% yield). The metal-free protocol represents unique example C-P bond formation through situ generation siloxycarbenes. This methodology features advantages operational simplicity, mild conditions, broad substrate scope, column free gram-scale synthesis.

Language: Английский

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Low-Valent Tungsten-Catalyzed Controllable Oxidative Dehydrogenative Coupling of Anilines

Organic Letters, Journal Year: 2022, Volume and Issue: 25(1), P. 240 - 245

Published: Dec. 27, 2022

Herein, we have developed an efficient tungsten-catalyzed homogeneous system for oxidative dehydrogenative coupling of anilines to selectively produce various azoaromatics and azoxyaromatics as well 2-substituted indolone N-oxides by simply regulating the reaction solvent with peroxide a terminal oxidant under additive-free conditions. These findings provide experimental framework exploring tungsten catalysis in organic synthesis offer convenient tactic selective oxidation anilines.

Language: Английский

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Lewis Acid-Catalyzed 1,3-Dipolar Cycloaddition of Bicyclobutanes with Isatogens: Access to Tetracyclic 2-Oxa-3-azabicyclo[3.1.1]heptanes

JACS Au, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 19, 2024

The 'escape from flatland' concept has gained significant traction in modern drug discovery, emphasizing the importance of three-dimensional molecular architectures, which serve as saturated bioisosteres benzenoids. Bicyclo[1.1.0]butanes (BCBs), known for their high ring strain and numerous reactivities, offer a simple yet effective method synthesizing these bicyclic frameworks. Although (3 + 2) annulations involving BCBs have been extensively studied, 1,3-dipolar cycloaddition leading to 3) annulation received limited attention. Herein, we report Lewis acid-catalyzed with isatogens allowing synthesis biologically relevant tetracyclic 2-oxa-3-azabicyclo[3.1.1]heptanes. Moreover, reaction can be performed one-pot process by situ generation 2-alkynylated nitrobenzenes. Additionally, preliminary mechanistic photophysical studies annulated products experiments toward asymmetric version this are also provided.

Language: Английский

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Phospha-Mannich reactions of phosphinous acids R ₂ P–OH and their derivatives

Phosphorus, sulfur, and silicon and the related elements, Journal Year: 2023, Volume and Issue: 198(11), P. 867 - 923

Published: July 20, 2023

Secondary phosphine oxides R2P(O)H are a relatively stable tautomeric form of secondary phosphinous acids R2P–OH that with imine/iminium species, or their donors, compounds P(O)–Csp3–N linkage (the phospha-Mannich reaction). These can be referred to as (α-aminoalkyl)phosphine oxides, (α-phosphinoylalkyl)amines, P(O),N-acetals. Compared P–Csp3–N linkages P,N-acetals, products reactions involving phosphines R2PH, the is significantly more allows for many examples α-functionalized P(O),N-acetals and α-phosphinoylated N-heterocycles, whereas such P,N-acetals rare. Trivalent derivatives halides R2P–Hal, esters R2P–OR' (phosphinites), amides R2P–NR'2 (aminophosphines), phosphides R2P–PR'2 (biphosphines) also participate in Mannich-type mechanisms depending on reactants. The react (α-alkoxyalkyl)amines (N,O-acetals) (α-haloalkyl)amines (N,Hal-acetals), respectively, via Arbuzov-type intermediates rearranged into alkyl (Arbuzov rearrangement). Furthermore, unlike phosphines, less sensitive oxidation, imines/iminium species generated not only under conventional Mannich conditions, i.e., from N,E-acetals (E = OH, O, N, halogen, etc.), but also, example, by oxidation α-C-atom amines, alcohols aldehydes than amines.

Language: Английский

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Gold‐Catalyzed Tandem Oxidation‐Migration of 3‐Propargyl Indoles: Synthesis of α‐Indol‐3‐yl α,β‐Unsaturated Carbonyls

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: 366(9), P. 2079 - 2089

Published: March 2, 2024

Abstract α‐Indol‐3‐yl α,β‐unsaturated carbonyl compounds are synthesized from 3‐propargyl indoles, obtained by direct propargylation of via a gold‐catalyzed tandem oxidation‐1,2‐indole migration reaction in the presence pyridine N ‐oxides. Fine‐tuning catalyst and oxidant enables indoles bearing different substituents. The order oxidation indole is determined terminal or internal nature alkyne moiety. In addition, process can be coupled with additional reactions, allowing an increase molecular complexity design more elaborated reactions. this sense, derivatives alkenyl substituent at position evolve through migration‐Nazarov cyclization producing α‐indolyl cyclopentenones.

Language: Английский

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Lewis Acid-Catalyzed 1,3-Dipolar Cycloaddition of Bicyclobutanes with Isatogens: Access to Indoxyl-Fused Bicyclo[3.1.1]heptanes

Published: Sept. 2, 2024

The 'escape from flatland' concept has gained significant traction in modern drug discovery, emphasizing the importance of three-dimensional molecular architectures, which serve as saturated bioisosteres benzenoids. Bicyclo[1.1.0]butanes (BCBs), known for their high ring strain and numerous reactivity, offer a simple yet effective method synthesizing these bicyclic frameworks. Although (3+2) annulations involving BCBs have been extensively studied, 1,3-dipolar cycloaddi-tion leading to (3+3) annulation received limited attention. Herein, we report Lewis acid-catalyzed cycloaddition with isatogens allowing synthesis biologically relevant indoxyl-fused bicy-clo[3.1.1]heptanes. Moreover, reaction can be performed one-pot by in-situ generation 2-alkynylated nitrobenzenes. Additionally, preliminary mechanistic photophysical studies annulated prod-ucts, experiments towards asymmetric version this are also provided.

Language: Английский

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KI-Catalyzed C(sp³)–H Amination and Acyloxylation of Indolin-3-ones Using Air as the Oxidant

Organic Letters, Journal Year: 2023, Volume and Issue: 25(45), P. 8162 - 8167

Published: Nov. 6, 2023

We have developed an efficient and green strategy for the synthesis of C2-amino indolin-3-ones C2-acyloxy via KI-catalyzed C(sp3)–H amination acyloxylation using air as oxidant. The reaction provides straightforward access to 2-substituted by direct functionalization at C2 position under mild conditions. Moreover, conditions enable a range complex pharmaceuticals, providing attractive products medicinal chemistry programs.

Language: Английский

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A gold-catalyzed cyclization/nucleophilic addition reaction of o-alkynylanilines with ynamides: stereoselective synthesis of 3-vinylindoles

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 11(4), P. 1112 - 1117

Published: Dec. 23, 2023

The steric hindrance effect of the JohnPhosAu(MeCN)SbF 6 ligand and π–π stacking interaction between phenyl group on indole ynamide enhance selectivity towards E -configuration in reaction.

Language: Английский

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