Application of Photoclick Chemistry for the Synthesis of Pyrazoles via 1,3-Dipolar Cycloaddition between Alkynes and Nitrilimines Generated In Situ
作者:Richard Remy、Christian G. Bochet
DOI:10.1002/ejoc.201701225
日期:2018.1.23
The photolysis of tetrazoles leads to the extrusion of dinitrogen and forms a reactive nitrile imine intermediate. The latter can then react in situ with alkynes in a [3+2] cycloaddition providing pyrazoles. Some reactivity trends were identified, such as a preference for electron‐poor alkynes. On the tetrazole part, there is a clear preference for either aromatic or conjugated substituents.
Bu<sub>4</sub>NI-Catalyzed, Radical-Induced Regioselective <i>N</i>-Alkylations and Arylations of Tetrazoles Using Organic Peroxides/Peresters
作者:Suresh Rajamanickam、Chitranjan Sah、Bilal Ahmad Mir、Subhendu Ghosh、Garima Sethi、Vinita Yadav、Sugumar Venkataramani、Bhisma K. Patel
DOI:10.1021/acs.joc.9b02875
日期:2020.2.21
using tert-butyl hydroperoxide (TBHP) as the methyl source, alkyl diacyl peroxides as the primary alkyl source, alkyl peresters as the secondary and tertiaryalkyl 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
Copper‐Catalyzed Photoinduced [3+3] Cycloaddition Reactions of α‐Acidic Isocyanides with Tetrazoles
作者:Hua‐Wei Liu、Yong‐Jiu Hao、Zhong‐Jian Cai、Shun‐Jun Ji
DOI:10.1002/adsc.202300598
日期:2023.11.7
photoinduced [3+3] cycloaddition reaction of α-acidic isocyanides with 2,5-diaryltetrazoles is described. The reaction proceeded smoothly with high regioselectivity, affording a range of important 1,2,4-triazines under mild conditions. The obtained 1,2,4-triazines were converted into triazine alcohol, Weinreb amide and triazinone easily, which further illustrate the utility of this [3+3] cycloaddition
Spirotriazolines and spirooxadiazolines are furnished in high yields at room temperature by the light-induced [3+2] cycloaddition with 2,5-diaryltetrazole as the precursor of nitrile imine. The use of light as the unique reagent and broad substrate scope are distinguishing features of this protocol.
One-Pot Reactions for Synthesis of 2,5-Substituted Tetrazoles from Aryldiazonium Salts and Amidines
作者:Mani Ramanathan、Yu-Hao Wang、Shiuh-Tzung Liu
DOI:10.1021/acs.orglett.5b03068
日期:2015.12.4
One-pot sequential reactions of aryldiazonium salts with amidines followed by the treatment of I-2/KI under basic conditions provide 2,5-disubstituted tetrazoles in moderate to excellent yields. This one-pot synthesis has several advantages such as mild reaction conditions, short reaction time, convenient workup, and high yields, making this methodology practical.