Recent Advance in Transition Metal‐Catalyzed Carboxylic Acid Guided B−H Functionalization of Carboranes

Advanced Synthesis & Catalysis, Journal Year: 2022, Volume and Issue: 364(24), P. 4174 - 4188

Published: Dec. 1, 2022

Abstract Carboranes, a three‐dimensional class of carbon‐boron molecular clusters with remarkable electronic, physical, chemical characteristics, have proved as useful building blocks in boron neutron capture therapy agents, supramolecular design, optoelectronics, nanomaterials and organometallic/coordination chemistry. Thus, various organic modifications the B−H C−H functionalities carboranes been developed. These methods great success utilize directing groups, such carboxylic acids, to achieve selective functionalization carboranes. The carboxyl group can be easily introduced then removed after reactions. On other hand, assisted by highly regioselective electrophilic attack at electron‐rich positions B(4) B(5) cage generates five‐membered metallacyclic intermediates, which undergo further transformation. In this review, we show that transition metal‐catalyzed decarboxylation cross coupling reactions offer an opportunity for direct activation magnified image

Language: Английский

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Electroreductive Carboxylation of Propargylic Acetates with CO₂: Access to Tetrasubstituted 2,3-Allenoates

Organic Letters, Journal Year: 2023, Volume and Issue: 25(51), P. 9176 - 9180

Published: Dec. 19, 2023

An electroreductive carboxylation of propargylic alcohols with CO2 and then workup TMSCHN2 to construct tetrasubstituted 2,3-allenoates is developed. This method allows the incorporation an external ester group into resulting allene system through electroreduction, carboxylation, deacetoxylation cascades. Mechanistically, electricity on/off experiments cyclic voltammetry analysis support preferential generation radical anion or 3-aryl acetate based on electron nature aryl rings.

Language: Английский

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Iridium-Catalyzed Regioselective B(4)-Alkenylation and B(3,5)-Dialkenylation of o-Carboranes

Organic Letters, Journal Year: 2023, Volume and Issue: 25(36), P. 6643 - 6648

Published: Aug. 30, 2023

Iridium(I)-catalyzed regioselective B(4)-alkenylation has been developed from o-carboranyl sulfoxonium ylides and alkynes through B(4)–H activation. The sequential B(4)- B(6)-alkenylation afforded B(3,5)-dialkenylated in one pot. Eventually, two alkenyl groups, the same or different, were introduced at positions 3 5 of carborane. Sulfoxonium ylide used as a directing group remains available for further functionalization is converted to B-alkenylated trichloromethyl ketones.

Language: Английский

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Directing Group Assisted Transition Metal Catalyzed Selective BH Functionalization of o-Carboranes

Synthesis, Journal Year: 2024, Volume and Issue: unknown

Published: June 11, 2024

Abstract Carboranes are a type of molecular clusters consisting carbon, hydrogen, and boron atoms. They possess unique characteristics, such as three-dimensional aromaticity, icosahedral geometry, robustness. Functionalized carboranes have been utilized in various fields, including medicine, materials, organometallic/coordination chemistry. In this context, selective functionalization o-carboranes has received tremendous attention, specifically the regio- enantioselective modification ten chemically similar BH vertices within carborane cage. recent years, significant progress made catalytic vertex-specific functionalization, well achieving cage BH. This review provides an overview advancements research field. 1 Introduction 2 Carboxy-Assisted Functionalization 2.1 Formation B–C Bonds 2.2 B–N 2.3 B–O 2.4 B–X 2.5 Consecutive B–Y (Y = N, O) 3 N-Based Directing-Group-Assisted B–H 3.1 Acylamino Directing Group 3.2 Amide 3.3 Pyridyl 3.4 Imine 4 Phosphinyl-Assisted Cage 5 Bidentate-Directing-Group-Assisted 6 Other 7 Conclusions

Language: Английский

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Regiodivergent metal-catalyzed B(4)- and C(1)-selenylation of o-carboranes

Chemical Science, Journal Year: 2022, Volume and Issue: 14(3), P. 643 - 649

Published: Dec. 3, 2022

Regiodivergent transition metal-catalyzed B(4)- and C(1)-selenylation reactions of o -carboranes have been demonstrated.

Language: Английский

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Synthesis of o-Carborane-Fused Pyrazoles through Sequential C–N Bond Formation

Organic Letters, Journal Year: 2022, Volume and Issue: 24(19), P. 3526 - 3531

Published: May 9, 2022

Transition-metal-free synthetic method for o-carborane-fused pyrazoles as a new scaffold has been developed from the reaction of B(4)-acylmethyl or B(3,5)-diacylmethyl o-carborane with 2-azido-1,3-dimethylimidazolinium hexafluorophosphate (ADMP) in presence DBU acetonitrile through sequential diazotization and cyclization one pot, consequently allowing twofold C-N bond formation under extremely mild conditions high functional group tolerance.

Language: Английский

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Iridium(III)-Catalyzed Regioselective B(4)–H Amination of o-Carboranes with Sufilimines

Organic Letters, Journal Year: 2023, Volume and Issue: 25(32), P. 5989 - 5994

Published: Aug. 4, 2023

Iridium(III)-catalyzed regioselective B(4)-H amination is developed from the reaction of o-carborane acids with sulfilimines without any oxidants under mild conditions, which leads to a wide range aminated o-carboranes in good yields broad substrate scope. Moreover, selective B(3,6)-diamination acid was achieved. The present attractive practical point view because dibenzothiophene quantitatively recovered and reused.

Language: Английский

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Ruthenium‐Catalyzed Selective B(4)‐H Amidation of o‐Carboranes with Dioxazolones

Asian Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 12(3)

Published: Dec. 21, 2022

Abstract A ruthenium‐catalyzed selective B4 amidation of o ‐carboranes with a variety alkyl‐, aryl‐, and heteroaryl‐substituted dioxazolones is developed by carboxylic acid‐assisted B(4)‐H bond activation in ‐carborane acids, affording multitude (4)‐amidated good yields the evolution carbon dioxide. In addition, two‐fold decarboxylative reaction cage was accomplished.

Language: Английский

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Synthesis of o‐carboranyl‐acyl‐substituted diazo compounds from B(4)‐acylmethyl carboranes and 2‐azido‐1,3‐dimethylimidazolinium hexafluorophosphate

Bulletin of the Korean Chemical Society, Journal Year: 2023, Volume and Issue: 44(8), P. 693 - 699

Published: April 28, 2023

Abstract Reaction of B(4)‐acylmethyl o ‐carborane with 2‐azido‐1,3‐dimethylimidazolinium hexafluorophosphate (ADMP) in the presence 1,8‐diazabicyclo[5.4.0]‐undec‐7‐ene (DBU) acetonitrile at 25 °C for 3 h produced a wide range ‐carboranyl‐acyl‐substituted diazo compounds high yields good functional group tolerance.

Language: Английский

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Diversity-Oriented Synthesis of Indole-Fused Polycyclic Scaffolds via Rhodium-Catalyzed NH-Indole-Directed C–H Coupling of 2-Phenyl-1H-indoles with Propargylic Alcohol Derivatives

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(8), P. 5589 - 5605

Published: April 5, 2024

Diversity-oriented synthesis strategy for the efficient assembly of indole-fused polycyclic scaffolds via rhodium-catalyzed NH-indole-directed C–H coupling with propargylic alcohol derivatives in a regioselective manner was developed. Five 2-phenyl-1H-indole-embedded core skeletons were synthesized. In particular, three different exo-olefin-containing polycycles realized, which may be manipulated further chemistry.

Language: Английский

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