Organic Letters, Год журнала: 2023, Номер 25(50), С. 8987 - 8991
Опубликована: Дек. 7, 2023
We report a rhodium-catalyzed asymmetric addition of aryl and alkenyl boronic acids to quinoxalinium salts that generates dihydroquinoxalines with high enantioselectivity. Functionalization the reaction products, dihydroquinoxaline, allows preparation tetrahydroquinoxalines various substitution patterns.
Язык: Английский
Organic & Biomolecular Chemistry, Год журнала: 2023, Номер 21(28), С. 5671 - 5690
Опубликована: Янв. 1, 2023
This review discusses known approaches for selective pyridine C–H editing, focusing on recent discoveries uniquely suited to pyridines.
Язык: Английский
Процитировано
32
Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(32)
Опубликована: Июнь 15, 2023
Abstract Asymmetric cross‐couplings based on 1,2‐carbon migration from B‐ate complexes have been developed efficiently to access valuable organoboronates. However, enantioselective reactions triggered by 1,2‐boron shift remained be unaddressed synthetic challenge. Here, Ir‐catalyzed asymmetric allylic alkylation enabled was developed. In this reaction, we disclosed that excellent enantioselectivities were achieved through an interesting dynamic kinetic resolution (DKR) process of carbonates at the elevated temperature. Notably, highly (bis‐boryl)alkenes array diversifications versatile molecules. Extensive experimental and computational studies conducted elucidate reaction mechanism DKR clarify origin enantioselectivities.
Язык: Английский
Процитировано
27
Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(34)
Опубликована: Июль 3, 2023
Abstract Herein, we report a one‐pot method for enantioselective C−H allylation of pyridines at C3 via tandem borane and palladium catalysis. This involves borane‐catalyzed pyridine hydroboration to generate dihydropyridines, then palladium‐catalyzed the dihydropyridines with allylic esters, finally air oxidation allylated afford products. enables introduction an group excellent regio‐ enantioselectivities.
Язык: Английский
Процитировано
26
Nature Communications, Год журнала: 2024, Номер 15(1)
Опубликована: Май 15, 2024
Abstract Difluoromethyl pyridines have gained significant attention in medicinal and agricultural chemistry. The direct C−H-difluoromethylation of represents a highly efficient economic way to access these azines. However, the meta-difluoromethylation has remained elusive methods for site-switchable regioselective meta- para-difluoromethylation are unknown. Here, we demonstrate meta-C−H-difluoromethylation through radical process by using oxazino pyridine intermediates, which easily accessed from pyridines. selectivity can be readily switched para situ transformation pyridinium salts upon acid treatment. preparation various para-difluoromethylated this approach is presented. mild conditions used also allow late-stage or containing drugs. Sequential double functionalization presented, further underlines value work.
Язык: Английский
Процитировано
13
Angewandte Chemie International Edition, Год журнала: 2025, Номер unknown
Опубликована: Янв. 9, 2025
Abstract Currently, the development of polymeric hole‐transporting materials (HTMs) lags behind that small‐molecule HTMs in inverted perovskite solar cells (PSCs). A critical challenge is conventional are incapable forming ultra‐thin and conformal coatings like self‐assembly monolayers (SAMs), especially for substrates with rough surface morphology. Herein, we address this by designing anchorable (CP1 to CP5). Specifically, coordinative pyridyl groups introduced as side‐chains on poly‐triarylamine (PTAA) backbone varied contents copolymerization method, resulting chemical interactions between substrates. The strong interaction allows them be processed into ultra‐thin, uniform, robust layers through employing low‐concentration solutions (0.1 mg mL −1 , vs. 2.0–5.0 PTAA), greatly decreasing charge transport losses. Moreover, upon systematically tuning substitution ratio, energy levels, wetting, solution processability, defect passivation capability such simultaneously optimized. Based optimal CP4, achieved highly efficient PSCs power conversion efficiencies (PCEs) up 26.21 %, which par state‐of‐the‐art SAM‐based PSCs. Furthermore, these devices exhibit enhanced stabilities under repeated current–voltage scans reverse bias ageing compared devices.
Язык: Английский
Процитировано
2
Nature Communications, Год журнала: 2024, Номер 15(1)
Опубликована: Авг. 28, 2024
Considering the indispensable significance and utilities of meta-substituted pyridines in medicinal, chemical as well materials science, a direct meta-selective C-H functionalization is paramount importance, but such reactions remain limited highly challenging. In general, established methods for meta rely on utilization tailored electrophilic reagents to realize intrinsic polarity match. Herein, we report complementary electrochemical methodology; diverse nucleophilic sulfinates allow meta-sulfonylation through redox-neutral dearomatization-rearomatization strategy by tandem dearomative cycloaddition/hydrogen-evolution electrooxidative sulfonation resulting oxazino-pyridines/acid-promoted rearomatization sequence. Besides, several salient features, including exclusive regiocontrol, remarkable substrate/functional group compatibility, scale-up potential, facile late-stage modification, have been demonstrated, which further contributes practicality adaptability this approach.
Язык: Английский
Процитировано
9
Angewandte Chemie International Edition, Год журнала: 2023, Номер 63(8)
Опубликована: Ноя. 21, 2023
Abstract An arylation protocol for pyridines is described, via the ring‐opened Zincke intermediate. Treatment of with triflic anhydride and a secondary amine produces an azahexatriene species, which undergoes regioselective Pd‐catalyzed at putative C4 position. Recyclization then provides pyridine products. Alternatively, metal‐free diaryliodonium salt selective meta ‐position, affording regiodivergent approach to biaryls from common
Язык: Английский
Процитировано
14
Chemical Science, Год журнала: 2024, Номер 15(31), С. 12442 - 12450
Опубликована: Янв. 1, 2024
A practical and general C-4 functionalization strategy of unbiased pyridines is developed by identifying a readily synthesized substituted urea as the pyridine activation reagent.
Язык: Английский
Процитировано
6
Chemical Science, Год журнала: 2024, Номер 15(34), С. 13923 - 13929
Опубликована: Янв. 1, 2024
There exists an interplay between borane and a Lewis base in their adducts. However, studies on these adducts so far have mainly focused the different reactions of B-H bonds with limited attention given to influence chemistry base, except for BF
Язык: Английский
Процитировано
6
Journal of the American Chemical Society, Год журнала: 2024, Номер 146(35), С. 24257 - 24264
Опубликована: Авг. 22, 2024
The C–H hydroxylation of the pyridine C3 position is a highly desirable transformation but remains great challenge due to inherent electronic properties this heterocycle core which bring difficulties in chemical reactivity and regioselectivity. Herein we present an efficient method for formal selective pyridines via photochemical valence isomerization N-oxides. This metal-free features operational simplicity compatibility with diverse array functional groups, resulting hydroxylated products are amenable further elaboration synthetically useful building blocks. synthetic utility strategy demonstrated effective late-stage functionalization pyridine-containing medicinally relevant molecules versatile derivatizations 3-pyridinols.
Язык: Английский
Процитировано
6