Cited by Pd-Catalyzed ortho-/meta-C-H-annulation of biphenyl amines with enynes through non-rollover cyclometallation

Photoinduced arylative formal 4-endo-dig cyclization of propargyl alcohols/amines to access strained heterocycles DOI

Pammi Venka Reddy, Attunuri Nagireddy, Jagadeesh Babu Nanubolu

et al.

Green Chemistry, Journal Year: 2024, Volume and Issue: 26(5), P. 2705 - 2711

Published: Jan. 1, 2024

A novel synthetic strategy to access strained heterocycles is revealed through photocatalysed annulative formal 4- endo-dig cyclization of propargyl alcohols/amines with benzoquinones under catalyst/reagent-free conditions using non-hazardous solvent.

Language: Английский

Citations

Pd-Catalyzed Sequential Electrophilic Cyclization/Selective C–H Annulation Cascade: Synthesis of Isoxazole-Phthalimide-Fused Poly-Heterocyclics DOI

V. Suresh,

T. Mahipal Reddy,

Dattatri

et al.

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(5), P. 3214 - 3225

Published: Feb. 21, 2024

Harnessing the organo-palladium intermediates generated from electrophilic cyclizations for tandem C–C bond construction is a challenging task but constitutes an excellent tool constructing complex motifs simpler substrates. We realize herein such cyclative annulation of alkynyl-oxime ethers with maleimides facile isoxazole-phthalimide hybrid through Pd(II) catalysis. This protocol features regio-selectivity in C–H selection, broad substrate scope, good functional group tolerance, and scalability. Necessary KIE & labeling studies give insight into reaction mechanism.

Language: Английский

Citations

Rhodium‐Catalyzed Dual C−H Activation for Regioselective Triple Annulation of Enaminones: Access to Polycyclic Naphthopyran Derivatives DOI

V. Suresh,

Muniganti Naveen Kumar,

Attunuri Nagireddy

et al.

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(11), P. 1770 - 1776

Published: March 21, 2023

Abstract Rh‐catalyzed C−H activation of arenes for oxidative annulations with alkynes stands out as a protocol polycyclic scaffolds. This perspective drives us to disclose herein rhodium catalyzed regioselective triple annulation enaminones hydroxyl‐alkynoates via double functionalization naphtho‐pyran Secondary coordination OH in alkynoate dictated the regioselectivity. Initial lactonization occurred chemoselectively on enamine part carbo rhodation followed by reductive elimination. was scalable and has shown high functionality tolerance. KIE studies were done get insight mechanism, some downstream transformations achieved show synthetic potential method.

Language: Английский

Citations

Rh(iii)-catalyzed selective mono- and dual-functionalization/cyclization of 1-aryl-5-aminopyrazoles with iodonium ylides DOI

Longkun Chen,

Mingshuai Zhang,

Meichen Liu

et al.

Chemical Communications, Journal Year: 2023, Volume and Issue: 60(4), P. 432 - 435

Published: Dec. 5, 2023

Highly functionalized benzodiazepine skeletons were efficiently synthesized via a Rh( iii )-catalyzed selective mono- and dual-C–H bond functionalization/cyclization reaction between readily available 1-aryl-5-aminopyrazoles iodonium ylides under.

Language: Английский

Citations

Pd-catalyzed regioselective rollover dual C–H annulation cascade: facile approach to phenanthrene derivatives DOI

Muniganti Naveen Kumar,

V. Suresh,

Attunuri Nagireddy

et al.

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(64), P. 9714 - 9717

Published: Jan. 1, 2023

A Pd-catalyzed rollover cascade dual C–H annulation of aryl phenols with alkynols for producing phenanthrene scaffolds in a regioselective manner was developed. Necessary control, KIE and deuterium experiments were conducted to determine the reaction mechanism.

Language: Английский

Citations

Pd-Catalyzed Chelation-Assisted Regioselective and Site Selective Cyclative C–H Annulation of Alkynyl Oximes with Activated Alkynes DOI

Ramesh Kotipalli,

Jagadeesh Babu Nanubolu, Maddi Sridhar Reddy

et al.

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(6), P. 3834 - 3843

Published: Feb. 29, 2024

Electrophilic cyclization and concomitant C–H annulation constitute an expedient cascade strategy for the construction of multicyclic scaffolds with precise substitutional patterns. We report here a novel Pd-catalyzed cyclative ynone oxime activated alkynes. The features dual regioselectivity including site selective activation chelation-assisted insertion Control experiments together kinetic give insights into mechanism.

Language: Английский

Citations

Pd-Catalyzed Selective Arylative Cascade Cyclization of 1,6-Diynes and Dibenzoxaborins for Fused Naphthalene Derivatives DOI

Muniganti Naveen Kumar,

Sriram Mahesh,

Jagadeesh Babu Nanubolu

et al.

The Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: April 10, 2025

A palladium-catalyzed new mode of cascade arylative cyclization 1,6-diynes is disclosed using dibenzoxaborin as an arylating agent featuring transmetalation and selective migratory insertion the key steps. This process enables efficient construction polysubstituted fused naphthalene skeletons via formation three C-C bonds through dual regioselectivity in both arylation well C-H functionalization. Some control experiments kinetic isotope effect (KIE) studies were conducted to elucidate reaction mechanism, some product diversifications achieved showcase synthetic potential.

Language: Английский

Citations

Rh-catalyzed chemo-, stereo- and regioselective C–H cascade annulation of indolyloxopropanenitriles for pyranoindoles DOI

Ramesh Kotipalli,

Undamatla Suri Babu,

Jagadeesh Babu Nanubolu

et al.

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(67), P. 10137 - 10140

Published: Jan. 1, 2023

Selective annulations of alkynes represent a powerful tool for constructing multicyclic scaffolds while installing desired substitution patterns with precision. Herein, we report Rh-catalyzed unique annulation indolyl oxopropanenitrile hydroxy-alkynoates to access pyranoindole cyclic motifs, featuring enol oxygen as rare chemoselective reactive terminal. The reaction proceeds via five-membered oxy-rodacycle through C-H activation by rhodium complex guided enolic- and propargyloxy dual co-ordination enable regio- stereoselective modular assembly.

Language: Английский

Citations

Construction of Rings via Metal‐Catalyzed C−H Annulation with Unsymmetrical Internal Alkynes: Selectivity and Applications DOI

Qiaoya Zhang,

Ci Chen,

Bairong Liu

et al.

ChemCatChem, Journal Year: 2023, Volume and Issue: 15(21)

Published: Aug. 19, 2023

Abstract Selective and concise construction of ring systems that are ubiquitous skeletons across chemistry, drugs materials, is indispensable for human life. Of note, directed C−H annulation with alkynes the expedient delivery holds great importance, featuring step‐ atom‐economy, mild conditions, broad substrate scope. However, regioselectivity issues remained when using unsymmetrical annulation. Herein, we summarized recent achievements towards solving this problem by developing directing groups, metal catalysts, versatile traceless functionality ensure overall regioselectivity, enantioselectivity, efficiency, synthetic application. We hope concept will promote further development precise functional molecules alkynes.

Language: Английский

Citations

Ruthenium-catalysed decarboxylative unsymmetric dual ortho-/meta-C–H bond functionalization of arenecarboxylic acids DOI

Xiankai Li, Xiaofei Wang, Jing Zhang

et al.

Chemical Science, Journal Year: 2023, Volume and Issue: 14(20), P. 5470 - 5476

Published: Jan. 1, 2023

We report a Ru-catalysed decarboxylative unsymmetric ortho -C–H azaarylation/ meta alkylation via traceless directing group relay strategy, which shows high regio- and chemoselectivity with broad substrate scopes under redox-neutral conditions.

Language: Английский

Citations