90766-67-9Relevant academic research and scientific papers
Nickel-Catalyzed, Regio- and Enantioselective Benzylic Alkenylation of Olefins with Alkenyl Bromide
Liu, Jiandong,Gong, Hegui,Zhu, Shaolin
supporting information, p. 4060 - 4064 (2020/12/25)
A NiH-catalyzed migratory hydroalkenylation reaction of olefins with alkenyl bromides has been developed, affording benzylic alkenylation products with high yields and excellent chemoselectivity. The mild conditions of the reaction preclude olefinic products from undergoing further isomerization or subsequent alkenylation. Catalytic enantioselective hydroalkenylation of styrenes was achieved by using a chiral bisoxazoline ligand.
Gold(I)-Catalyzed Oxidative 1,4-Additions of 3-En-1-ynamide with Nitrones via Carbon- versus Nitrogen-Addition Chemoselectivity
Tanpure, Sudhakar Dattatray,Kale, Balaji S.,Liu, Rai-Shung
supporting information, p. 1394 - 1399 (2021/02/20)
This work reports gold-catalyzed 1,4-oxofunctionalizations of 3-en-1-ynamides with nitrones, yielding two distinct E-configured products. We obtained 1,4-oxoarylation products from 3-en-1-ynamides bearing C(4)-electron-donating substituents and 1,4-oxoamination products from those analogues bearing C(4)-aryl substituents. We propose that if vinylgold carbenes are stable, imines undergo a para-arylation on these gold carbenes. If vinylgold carbenes are highly electron-deficient, this N-attack is irreversible to enable 1,4-oxoaminations.
Electrochemical Nozaki-Hiyama-Kishi Coupling: Scope, Applications, and Mechanism
Baran, Phil S.,Blackmond, Donna G.,Gao, Yang,Hadt, Ryan G.,Hao, Wei,Hill, David E.,McNicholas, Brendon J.,Reisman, Sarah E.,Vantourout, Julien C.
supporting information, p. 9478 - 9488 (2021/07/19)
One of the most oft-employed methods for C-C bond formation involving the coupling of vinyl-halides with aldehydes catalyzed by Ni and Cr (Nozaki-Hiyama-Kishi, NHK) has been rendered more practical using an electroreductive manifold. Although early studies pointed to the feasibility of such a process, those precedents were never applied by others due to cumbersome setups and limited scope. Here we show that a carefully optimized electroreductive procedure can enable a more sustainable approach to NHK, even in an asymmetric fashion on highly complex medicinally relevant systems. The e-NHK can even enable non-canonical substrate classes, such as redox-active esters, to participate with low loadings of Cr when conventional chemical techniques fail. A combination of detailed kinetics, cyclic voltammetry, and in situ UV-vis spectroelectrochemistry of these processes illuminates the subtle features of this mechanistically intricate process.
Cyclization of 1-Aryl-5-Phenylpent-4-en-2-yn-1-Ones to 2,3-Dihydropyran-2-Ones in Trifluoromethanesulfonic Acid
Zalivatskaya, Anna S.,Golovanov, Aleksander А.,Vasilyev, Aleksander V.
, p. 953 - 956 (2020/08/26)
[Figure not available: see fulltext.] Under the action of an excess of trifluoromethanesulfonic acid, 1-aryl-5-phenylpent-4-en-2-yn-1-ones cyclize intramolecularly to 6-aryl-2-phenyl-2,3-dihydropyran-4-ones. The reaction proceeds at room temperature for 1
Fischer Carbene Pentannulation with Alkynes Having Adjacent Carbonate or Acyloxy Groups: Synthesis of 3-Substituted 1-Indanones
Bhattacharyya, Shubhankar,Chavan, Vijay P.,Fernandes, Rodney A.,Gholap, Sachin P.,Saiyed, Akeel S.
supporting information, p. 3438 - 3443 (2020/04/20)
Various aryl Fischer carbenes reacted with alkynes having adjacent acyloxy or carbonate groups to regioselectively deliver 3-substituted 1-indanones. The acyloxy or carbonate group probably coordinates with the Cr metal to give a tetra-coordinated chromium complex forming a six-membered ring that retards CO insertion for ketene formation, which is required for benzannulation. Alternatively, the ortho position aryl ring attack results in pentannulation, providing regioselectively 3-substituted 1-indanones. The method is extended to the synthesis of the core structure of 3-epi-mutisianthol.
Iron(II)-Based Metalloradical Activation: Switch from Traditional Click Chemistry to Denitrogenative Annulation
Roy, Satyajit,Khatua, Hillol,Das, Sandip Kumar,Chattopadhyay, Buddhadeb
supporting information, p. 11439 - 11443 (2019/07/17)
A unique concept for the intermolecular denitrogenative annulation of 1,2,3,4-tetrazoles and alkynes was discovered by using a catalytic amount of Fe(TPP)Cl and Zn dust. The reaction precludes the traditional, more favored click reaction between an organic azide and alkynes, and instead proceeds by an unprecedented metalloradical activation. The method is anticipated to advance access to the construction of important basic nitrogen heterocycles, which will in turn enable discoveries of new drug candidates.
Cs2CO3-Mediated Vicinal Thiosulfonylation of 1,1-Dibromo-1-Alkenes with Thiosulfonates: An Expedient Synthesis of (E)-1,2-Thiosulfonylethenes
Reddy, Raju Jannapu,Kumari, Arram Haritha,Kumar, Jangam Jagadesh,Nanubolu, Jagadeesh Babu
supporting information, p. 1587 - 1591 (2019/02/16)
A new and highly efficient vicinal thiosulfonylation of 1,1-dibromo-1-alkenes with thiosulfonates in the presence of cesium carbonate has been developed. The metal-free diheterofunctionalization is an operationally simple to access a wide range of (E)-1,2-thiosulfonylethenes (α-aryl-β-thioarylvinyl sulfones) in moderate to high yields with high levels of stereoselectivities. Further, scalable reactions have been demonstrated for this transformation, thus illustrating its efficiency and practicality. (Figure presented.).
Enantioselective Reaction of 2H-Azirines with Phosphite Using Chiral Bis(imidazoline)/Zinc(II) Catalysts
Nakamura, Shuichi,Hayama, Daiki
supporting information, p. 8785 - 8789 (2017/07/17)
The first highly enantioselective nucleophilic addition reaction of phosphites with 2H-azirines has been developed. The reaction was applied to various 3-substituted 2H-azirines using novel chiral bis(imidazoline)/ZnII catalysts to afford produ
Iodine-Catalyzed Synthesis of Chalcogenophenes by the Reaction of 1,3-Dienyl Bromides and Potassium Selenocyanate/Potassium Sulfide (KSeCN/K2S)
Maity, Pintu,Ranu, Brindaban C.
, p. 4369 - 4378 (2017/12/26)
The methods available for the synthesis of chalcogenophenes, in general, are associated with drawbacks of harsh conditions, use of costly metals, broad applicability, tedious purification process and low yield. To avoid these drawbacks a transition metal-free iodine-catalyzed reaction of aryl-susbstituted 1,3-dienyl bromides with potassium selenocyanate/potassium sulfide (KSeCN/K2S) leading to the corresponding selenophenes and thiophenes has been developed. Iodine is relatively benign, less expensive and readily available. Several diversely substituted selenophenes and thiophenes have been obtained by this procedure in high yields. Using this procedure 2-(4-chlorophenyl)thiophene, a key intermediate for the synthesis of a melanin concentrating hormone receptor ligand involved in the treatment of eating disorders, weight gain, obesity, depression and anxiety has been synthesized. Although the reaction is one-pot essentially it proceeds in two steps involving a selenocyanate/thiolate intermediate leading to the selenophene/thiophene. The simple operation, use of inexpensive reagents and a metal-free process make this procedure more attractive for an easy access to substituted selenophenes and thiophenes. (Figure presented.).
Nickel-Catalyzed Reductive Cross-Coupling of Vinyl Bromides with Unactivated Alkyl Halides
Gu, Jun,Qiu, Canbin,Lu, Wenbin,Qian, Qun,Lin, Kunhua,Gong, Hegui
supporting information, p. 1867 - 1873 (2017/04/06)
The use of pyridine as the sole ligand for the reductive vinylation of unactivated secondary alkyl halides under Ni-catalyzed conditions has been developed. Both alkyl- and aryl-substituted vinyl bromides are suitable, in which alkyl-decorated α-alkenyl bromides resulted in the α-products in good results.
