Results 11 to 20 of about 17,602 (278)

Cascade Amination and Aza-6π-Annulation-Aromatization Strategy for the Synthesis of β‑Pyrimidine-Fused Porphyrins

, 2023
Novel nickel(II) and copper(II) complexes of 2-(N,N-dimethylformamidine)-3-formyl-5,10,15,20-tetraarylporphyrins have been synthesized for the first time from 2-aminoporphyrins under Vilsmeier–Haack conditions.
Jagmeet Singh, Pargat Singh (10898277), Jagmeet Singh (9486048), Pargat Singh, Mahendra Nath, Mahendra Nath (2695399)   +5 more
core   +1 more source

Reversing the Regioselectivity of Asymmetric C ̶ H and N ̶ H Bond Annulation with Bromoalkynes Under Cobalt(III)-Catalysis

, 2023
Metal-catalyzed C-H bond annulation strategy offers a versatile platform, allowing the construction of complex p-chiral molecules through atom- and step-economical fashion. However, regioselective insertion of -coupling partner between M-C bond and high
Subramani , Kumaran, Harihara , Subramanian, basker, sundararaju, Rajib, Mandal, Abir , Das   +4 more
core   +1 more source

Indium(III)-Catalysed [3+2] Annulation Reaction of Alkenes with α,β-Unsaturated Keto-Carboxylic Acid Derivatives for the Synthesis of γ-Butyrolactones

, 2023
Herein, we report In(OTf)3 catalyzed (3+2) annulation reaction of an alkene with α,β-unsaturated keto-carboxylic acid for the synthesis of γ-butyrolactone derivatives.
Gnanaprakasam, Boopathy, Somnath , Ghosh, Nilima Priyadarshini , Mishra, Mallika , Swaminathan, Nirmala, Mohanta   +4 more
core   +1 more source

Construction of Seven-Membered Cycles through Base Promoted [4+3] Domino Annulation of Crotonate-derived Sulfur Ylides with Diene

, 2022
A sequential [4+3] domino annulation of crotonate-derived Sulfur Ylides with Diene has been reported. With base promoted, this general method can realize the synthesis of highly functional none-fused cycles including nitrogen heterocycles and carbocycles
Joost, Berkhong, Yang, Liu
core   +1 more source

Base-Promoted Annulation of Amidoximes with Alkynes: Simple Access to 2,4-Disubstituted Imidazoles

Molecules, 2020
An efficient construction of imidazole ring by a Cs2CO3-promoted annulation of amidoximes with terminal alkynes in DMSO has been developed. This protocol provides a simple synthetic route with high atom-utilization for the synthesis of 2,4-disubstituted ...
Hina Mehmood, Muhammad Asif Iqbal, Le Lu, Ruimao Hua   +3 more
doaj   +1 more source

Sulfur Versus Nitrogen Chelation in C-H Activation: Cobalt(III)-Catalyzed Unsymmetrical Double Annulation of Thioamides

, 2021
An unconventional cobalt(III)-catalyzed one-pot domino double annulation of aryl thioamides with unactivated alkynes is presented. Sulfur (S), nitrogen (N), and o,o\u27-C-H bonds of aryl thioamides are involved in this reaction, enabling access to rare 6,
Vincent, Gandon, Arghadip, Ghosh, Somratan, Sau, Majji, Shankar, Akhila, Sahoo, Arijit, Saha   +5 more
core   +1 more source

Establishing the concept of aza-[3 + 3] annulations using enones as a key expansion of this unified strategy in alkaloid synthesis

Beilstein Journal of Organic Chemistry, 2013
A successful enone version of an intramolecular aza-[3 + 3] annulation reaction is described here. Use of piperidinium trifluoroacetate salt as the catalyst and toluene as the solvent appears to be critical for a successful annulation.
Aleksey I. Gerasyuto, Zhi-Xiong Ma, Grant S. Buchanan, Richard P. Hsung   +3 more
doaj   +1 more source

[4+3]-Annulation of 3-Cyano-4-aryl-2-iminochromenes with 1,2-Diaminobenzene: An Access to Novel Chromenobenzodiazepines

SynOpen, 2018
3-Cyano-4-aryl-2-iminochromenes undergo [4+3]-annulation with 1,2-diaminobenzene under mild acidic conditions to generate novel chromenobenzodiazepines in good yields.
Mohini Mourya, Himanshu Sharma, Yogesh C. Joshi, Ashok K. Basak   +3 more
doaj   +1 more source

Ru(II)-Catalyzed C(sp2)–H Activation Annulation: Synthesis of Fluorescent Benzoisoquinolonyl Acetate/Peptides from N-Arylamides and Ethyne at Room Temperature

, 2023
Benzoisoquinolones are aryl ring extended isoquinolinone derivatives, constituents of alkaloid natural products. This report describes the synthesis of benzoisoquinolones amino acids/peptides derivatives from respective N-aryl amino esters /peptides ...
Nagendra, Sharma, Ankita, Panda, Manish K, Gupta   +2 more
core   +1 more source

Electrophilically Activated Nitroalkanes in Synthesis of 3,4-Dihydroquinozalines

Molecules, 2021
Nitroalkanes activated with polyphosphoric acid serve as efficient electrophiles in reactions with various nucleophilic amines. Strategically placed second functionality allows for the design of annulation reactions enabling preparation of various ...
Alexander V. Aksenov, Igor Yu. Grishin, Nicolai A. Aksenov, Vladimir V. Malyuga, Dmitrii A. Aksenov, Mezvah A. Nobi, Michael Rubin   +6 more
doaj   +1 more source