1119-57-9Relevant academic research and scientific papers
Towards supramolecular fixation of NOx gases: Encapsulated reagents for nitrosation
Kang, Yanlong,Zyryanov, Grigory V.,Rudkevich, Dmitry M.
, p. 1924 - 1932 (2005)
The use of simple calix[4]arenes for chemical conversion of NO2/ N2O4 gases is demonstrated in solution and in the solid state. Upon reacting with these gases, calixarenes 1 encapsulate nitrosonium (NO+) cations within their cavities with the formation of stable calixarene-NO+ complexes 2. These complexes act as encapsulated nitrosating reagents; cavity effects control their reactivity and selectivity. Complexes 2 were effectively used for nitrosation of secondary amides 5, including chiral derivatives. Unique size-shape selectivity was observed, allowing for exclusive nitrosation of less crowded N-Me amides 5a-e (up to 95% yields). Bulkier N-Alk (Alk > Me) substrates 5 did not react due to the hindered approach to the encapsulated NO+ reagents. Robust, silica gel based calixarene material 3 was prepared, which reversibly traps NO 2/ N2O4 with the formation of NO +-storing silica gel 4. With material 4, similar size-shape selectivity was observed for nitrosation. The N-Me-N-nitroso derivatives 6d,e were obtained with ～30% yields, while bulkier amides were nitrosated with much lower yields (+ species, which can be generated by a number of NOx gases, these supramolecular reagents and materials may be useful for NOx entrapment and separation in the environment and biomedical areas.
Ligand-Controlled Regiodivergent Catalytic Amidation of Unactivated Secondary Alkyl Bromides
Tortajada, Andreu,Menezes Correia, Jose Tiago,Serrano, Eloisa,Monleón, Alicia,Tampieri, Alberto,Day, Craig S.,Juliá-Hernández, Francisco,Martin, Ruben
, p. 10223 - 10227 (2021/08/24)
A regiodivergent Ni-catalyzed amidation of unactivated secondary alkyl bromides is described. The site-selectivity of the amidation event is dictated by subtle differences on the ligand backbone, allowing introduction of the amide function at either the original sp3 carbon-halide bond or at distal sp3 C-H sites within an alkyl side-chain via chain-walking scenarios.
Chemoselective Synthesis of Aryl Ketones from Amides and Grignard Reagents via C(O)-N Bond Cleavage under Catalyst-Free Conditions
Sureshbabu, Popuri,Azeez, Sadaf,Muniyappan, Nalluchamy,Sabiah, Shahulhameed,Kandasamy, Jeyakumar
, p. 11823 - 11838 (2019/10/02)
Conversion of a wide range of N-Boc amides to aryl ketones was achieved with Grignard reagents via chemoselective C(O)-N bond cleavage. The reactions proceeded under catalyst-free conditions with different aryl, alkyl, and alkynyl Grignard reagents. α-Ketoamide was successfully converted to aryl diketones, while α,β-unsaturated amide underwent 1,4-addition followed by C(O)-N bond cleavage to provide diaryl propiophenones. N-Boc amides displayed higher reactivity than Weinreb amides with Grignard reagents. A broad substrate scope, excellent yields, and quick conversion are important features of this methodology.
A Practical and Chemoselective Ammonia-Free Birch Reduction
Lei, Peng,Ding, Yuxuan,Zhang, Xiaohe,Adijiang, Adila,Li, Hengzhao,Ling, Yun,An, Jie
supporting information, p. 3439 - 3442 (2018/06/26)
A novel protocol for a significantly improved, practical, and chemoselective ammonia-free Birch reduction mediated by bench-stable sodium dispersions and recoverable 15-crown-5 ether is reported. A broad range of aromatic and heteroaromatic compounds is reduced with excellent yields.
NOVEL BIAROMATIC COMPOUNDS THAT MODULATE PPAR-RECEPTORS
-
Page/Page column 9, (2009/01/23)
Novel biaromatic compounds that modulate peroxisome proliferator-activator receptors, known as PPAR, having the formula (I): are formulated into pharmaceutical compositions useful in human or veterinary medicine, or alternatively, in cosmetic compositions.
NOVEL BIAROMATIC COMPOUNDS WHICH ACTIVATE RECEPTORS OF PPAR TYPE AND THEIR USE IN COSMETIC OR PHARMACEUTICAL COMPOSITIONS
-
Page/Page column 17, (2010/10/20)
The invention relates to novel biaromatic compounds which correspond to the following general formula (I) and to their method of preparation and to their use in pharmaceutical compositions intended for use in human or veterinary medicine (in dermatology a
NOVEL COMPOUNDS THAT MODULATE PPARγ TYPE RECEPTORS, AND USE THEREOF IN COSMETIC OR PHARMACEUTICAL COMPOSITIONS
-
Page/Page column 26-27, (2010/11/08)
The invention relates to novel compounds corresponding to the general formula (I) below: and also to the method for preparing them, and to their use in pharmaceutical compositions intended for use in human or veterinary medicine (in dermatology, and also
Toward Synthetic Tubes for NO2/N2O4: Design, Synthesis, and Host-Guest Chemistry
Zyryanov, Grigory V.,Rudkevich, Dmitry M.
, p. 4264 - 4270 (2007/10/03)
Design of molecular nanotubes is proposed for entrapment and conversion of NO2/N2O4 gases. Synthesis of 1,3-alternate bis-calix[4]arene tube 3 of 5 × 11 A internal dimensions is presented, and its reversible reactions with
Encapsulated reagents for nitrosation
Zyryanov, Grigory V.,Rudkevich, Dmitry M.
, p. 1253 - 1256 (2007/10/03)
(Matrix presented) A novel class of stable, mild, and size-shape-selective nitrosating agents for secondary amides is introduced. These are based on reversible entrapment and release of reactive nitrosonium species by calix[4]arenes. The NO+ encapsulation controls the reaction selectivity.
