1620-53-7Relevant articles and documents
Asymmetric transfer hydrogenation of heterocycle-containing acetophenone derivatives using N-functionalised [(benzene)Ru(II)(TsDPEN)] complexes
Barrios-Rivera, Jonathan,Xu, Yingjian,Clarkson, Guy J.,Wills, Martin
, (2021/12/02)
The application of enantiomerically-pure ruthenium(II) catalysts containing N - functionalised TsDPEN ligand to the asymmetric transfer hydrogenation of 15 examples of α-heterocyclic acetophenone derivatives is reported. Products of up to 99% ee were formed.
Copper-Catalyzed Bisannulations of Malonate-Tethered O-Acyl Oximes with Pyridine, Pyrazine, Pyridazine, and Quinoline Derivatives for the Construction of Dihydroindolizine-Fused Pyrrolidinones and Analogues
Miao, Chun-Bao,Guan, Hong-Rong,Tang, Yihan,Wang, Kun,Ren, Wen-Long,Lyu, Xinyu,Yao, Changsheng,Yang, Hai-Tao
supporting information, p. 8699 - 8704 (2021/11/20)
A copper-catalyzed bisannulation reaction of malonate-tethered O-acyl oximes with pyridine, pyrazine, pyridazine, and quinoline derivatives has been developed for the concise synthesis of structurally novel dihydroindolizine-fused pyrrolidinones and their analogues. The present reaction shows excellent regioselectivity and stereoselectivity. Theoretical calculations reveal that the coordination effect of the carbonyl group in the nucleophilic substrate determines the excellent regioselectivity. Further functionalization of the generated dihydroindolizine-fused pyrrolidinone could be easily realized through substitution, Michael addition, selective aminolysis, and hydrolysis reactions.
Tandem Pd-Catalyzed Intermolecular Allylic Alkylation/Allylic Dearomatization Reaction of Benzoylmethyl pyridines, Pyrazines, and Quinolines
Zhang, Hui-Jun,Yang, Ze-Peng,Gu, Qing,You, Shu-Li
supporting information, (2019/05/08)
An efficient synthesis of nitrogen-containing heterocycles via Pd-catalyzed tandem allylic alkylation and dearomatization reactions was reported. In this reaction design, heteroarenes such as pyridines, pyrazines, and quinolines serve as bis-nucleophiles by installing a benzoyl group at the C2 benzylic position. With but-2-ene-1,4-diyl dimethyl dicarbonate as the bis-electrophile, the tandem Pd-catalyzed intermolecular allylic alkylation/allylic dearomatization reaction of benzoylmethyl-substituted heteroarenes has been developed. 2,3-Dihydroindolizine, 6,7-dihydropyrrolo[1,2-a]pyrazine, and 1,2-dihydropyrrolo[1,2-a]quinolin derivatives were obtained in moderate to good yields.
Highly efficient asymmetric bioreduction of 1-aryl-2-(azaaryl)ethanones. Chemoenzymatic synthesis of lanicemine
Liz, Ramón,Liardo, Elisa,Rebolledo, Francisca
supporting information, p. 8214 - 8220 (2019/09/19)
Different ketoreductases (KREDs) have been used to promote a highly selective reduction of several 1-aryl-2-(azaaryl)ethanones (azaaryl = pyridinyl, quinolin-2-yl), the corresponding secondary alcohols being obtained with very high yields and enantiomeric excesses (ee > 99%). The absolute configuration of each optically active alcohol has been assigned by means of modified Mosher and Kelly methods, two shielding effects being evaluated: (1) the Mosher phenyl ring effect on the azaaryl protons and (2) the one of the azaaryl ring on the Mosher methoxy group. In addition, the biologically active amine lanicemine has been synthesized from (R)-1-phenyl-2-(pyridin-2-yl)ethanol, thus proving the utility of the secondary alcohols here prepared.
Stereo- and regioselective gold(i)-catalyzed hydroamination of 2-(arylethynyl)pyridines with anilines
Cacchi, Sandro,Fabrizi, Giancarlo,Fochetti, Andrea,Ghirga, Francesca,Goggiamani, Antonella,Iazzetti, Antonia
, p. 527 - 532 (2019/01/24)
The gold-catalyzed hydroamination of 2-(arylethynyl)pyridines with anilines affords stereoselectively Z-enamine products with excellent regioselectivity. The reaction proceeds with moderate to excellent yields and accommodates a diverse range of functional groups on alkynes (ether, bromo, trifluoromethyl, acetyl, and carbomethoxy) and anilines (ether, bromo, chloro, and carbethoxy). The stereochemistry of the obtained enamines is complementary to that reported in previous studies. A plausible explanation for the observed selectivity was attained by means of NMR experiments.
Convenient Synthesis of Polyaza-2-(heteroaryl)pyridine Derivatives
Masaret, Ghada S.
, p. 610 - 618 (2018/03/21)
A simple and efficient method for the synthesis of new heterocyclic compounds containing pyridine and 1,3-pyrimidine units has been developed. It is based on the reaction of the appropriate enaminone with some N-nucleophiles.
Two-Step One-Pot Synthesis of Unsymmetrical (Hetero)Aryl 1,2-Diketones by Addition-Oxygenation of Potassium Aryltrifluoroborates to (Hetero)Arylacetonitriles
Kumar, Yogesh,Jaiswal, Yogesh,Kumar, Amit
, p. 494 - 505 (2018/02/09)
An efficient one-pot two-step procedure for the synthesis of unsymmetrical (hetero)aryl 1,2-diketones has been developed. The reaction proceeds through a palladium-catalyzed nucleophilic addition of potassium aryltrifluoroborates to aliphatic nitriles followed by a copper-catalyzed aerobic benzylic C–H oxygenation using molecular oxygen as a green oxidant. This represents the first example of the direct synthesis of unsymmetrical diaryl 1,2-diketones from arylacetonitriles. This method utilizes inexpensive, stable, nontoxic, and readily available starting materials, is highly effective in the presence of both electron-rich and electron-poor nitriles and aryltrifluoroborates, and tolerates a wide variety of functional groups. The synthetic utility of this transformation was shown by increasing the scale of the reaction and by carrying out the one-pot protocol for the preparation of quinoxaline and benzimidazole derivatives. A plausible reaction mechanism has also been proposed.
A new synthetic route to benzophenone derivatives
Abu-Melha, Sraa
, p. 313 - 316 (2017/08/15)
The rearrangement reaction of 1-alkyl-2-(benzoylmethyl)pyridinium iodides 3a-d, 6 in the presence of various nucleophiles leads to 2-alkylaminobenzophenone derivatives 4a-c. Best results were achieved with alkylammonium sulfites as recyclization reagents.
Highly Stereoselective Synthesis of Tetrasubstituted Acyclic All-Carbon Olefins via Enol Tosylation and Suzuki-Miyaura Coupling
Li, Beryl X.,Le, Diane N.,Mack, Kyle A.,McClory, Andrew,Lim, Ngiap-Kie,Cravillion, Theresa,Savage, Scott,Han, Chong,Collum, David B.,Zhang, Haiming,Gosselin, Francis
supporting information, p. 10777 - 10783 (2017/08/15)
A highly stereocontrolled synthesis of tetrasubstituted acyclic all-carbon olefins has been developed via a stereoselective enolization and tosylate formation, followed by a palladium-catalyzed Suzuki-Miyaura cross-coupling of the tosylates and pinacol boronic esters in the presence of a Pd(OAc)2/RuPhos catalytic system. Both the enol tosylation and Suzuki-Miyaura coupling reactions tolerate an array of electronically and sterically diverse substituents and generate high yield and stereoselectivity of the olefin products. Judicious choice of substrate and coupling partner provides access to either the E- or Z-olefin with excellent yield and stereochemical fidelity. Olefin isomerization was observed during the Suzuki-Miyaura coupling. However, under the optimized cross-coupling reaction conditions, the isomerization was suppressed to 5% in most cases. Mechanistic probes indicate that the olefin isomerization occurs via an intermediate, possibly a zwitterionic palladium carbenoid species.
Full Cleavage of C≡C Bond in Electron-Deficient Alkynes via Reaction with Ethylenediamine
Vasilevsky, Sergei F.,Davydova, Maria P.,Mamatyuk, Victor I.,Tsvetkov, Nikolay,Hughes, Audrey,Baranov, Denis S.,Alabugin, Igor V.
, p. 421 - 429 (2017/04/07)
Reaction of 1,2-diaminioethane (ethylenediamine) with electron-deficient alkynes leads to full scission of the C≡C bond even in the absence of a keto group directly attached to the alkyne. This process involves oxidation of one of the alkyne carbons into C2 of a 2-R-4,5-dihydroimidazole with the concomitant reduction of the other carbon to a methyl group. The sequence of Sonogashira coupling with the ethylenediamine-mediated fragmentation described in this work can be used for selective formal substitution of halogen in aryl halides by a methyl group or a 4,5-dihydroimidazol-2-yl moiety.
