18039-45-7Relevant articles and documents
Regioselective arylation of N-tributylstannylated 5-substituted tetrazoles by diaryliodonium salts in the presence of Cu(OAc)2
Davydov, Dmitri V.,Beletskaya, Irina P.,Semenov, Boris B.,Smushkevich, Yuri I.
, p. 6217 - 6219 (2002)
The arylation of N-tributylstannylated 5-substituted tetrazoles with diaryliodonium salts at room temperature without base in CH2Cl2 in the presence of stoichiometric amounts of Cu(OAc)2 proceeds regioselectively at the N-
Bu4NI-Catalyzed, Radical-Induced Regioselective N-Alkylations and Arylations of Tetrazoles Using Organic Peroxides/Peresters
Ghosh, Subhendu,Mir, Bilal Ahmad,Patel, Bhisma K.,Rajamanickam, Suresh,Sah, Chitranjan,Sethi, Garima,Venkataramani, Sugumar,Yadav, Vinita
, p. 2118 - 2141 (2020/03/13)
Bu4NI-catalyzed regioselective N2-methylation, N2-Alkylation, and N2-Arylation of tetrazoles have been achieved using tert-butyl hydroperoxide (TBHP) as the methyl source, alkyl diacyl peroxides as the primary alkyl source, alkyl peresters as the secondary and tertiary alkyl sources, and aryl diacyl peroxides as the arylating source. These reactions proceed without pre-functionalization of tetrazole and in the absence of any metal catalysts. Here, peroxides serve the dual role of oxidants as well as alkylating or arylating agents. Based on DFT calculations, it was found that spin density, transition-state barriers (kinetic control), and thermodynamic stability of the products (thermodynamic control) play essential roles in the observed regioselectivity during N-Alkylation. This radical-mediated process is amenable to a broad range of substrates and provides products in moderate to good yields.
Application of Photoclick Chemistry for the Synthesis of Pyrazoles via 1,3-Dipolar Cycloaddition between Alkynes and Nitrilimines Generated In Situ
Remy, Richard,Bochet, Christian G.
, p. 316 - 328 (2018/01/27)
The photochemical extrusion of gaseous nitrogen from 2,5-disubstituted tetrazoles to generate reactive nitrilimines in situ represents an efficient and attractive way to form dipoles that can be used to provide useful chemicals via 1,3-dipolar cycloadditions. The concept of “photoclick chemistry” already inspired numerous researchers, who exploited photochemical processes involving alkenes for the synthesis of adducts or the functionalization of biocompatible materials. The approach requires bioorthogonality, ease of access to the starting materials and operational simplicity. We report herein our investigations toward a photoclick reaction involving 2,5-disubstituted tetrazoles and alkynes as the dipolarophile for the synthesis of pyrazole derivatives. In addition to the numerous reports recently published on the synthesis of pyrazoles, we wish to add to the list a photochemical procedure that represents a mild and atom-economical alternative. Moreover, considering that such nitrilimines precursors can be accessed in one step from inexpensive and abundant starting materials and given the commercial availability of a broad spectrum of alkynes, we examined the scope of the photoclick reaction with respect to reactive partners, enabling the synthesis of a library of useful heteroaromatics.