Tetrazole syntheses

Similar to 1,2,3-triazoles, tetrazoles can also be synthesized by [3-(-2] cycloadditions [88]. 

18) You probably recognize the feces of these molecules from Chapters 3 and 4. 

NaNs (1.1 equiv) ZnBr2 (1 equiv), water, reflux 

This was followed by a report on the efficient synthesis of tetrazole analogs of a-amino acids by Demko and Sharpless [91]. The yields again were very high, and the scope broad, but the conditions a little bit milder than the previous ones (a reaction temperature of 80 °C was required). 

In 2012, Agawane and Nagarkar [92] reported the synthesis of tetrazoles using a nano-ZnO/CojO, catalyst. The scope was not very comprehensive, as NaNj was reacted with benzonitrile and four other derivatives. High temperatures were again required. 

Since 1901, conventional synthesis of 5-substituted l//-tetrazoles has been reported to proceed via [3-1-2] cycloaddition between azide and nitriles. Drawbacks from this procedure are the use of expensive and toxic azide, highly moisture-sensitive reaction conditions, strong Lewis acids, and hydrazoic acid. 

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Tetrazole synthesis (torn azides by dipolar cycloadd ition with activaled n ltnies or intramolecularly with nitriles in the presence of acids. 

Taclamine, 224 Talampicillin, 438 Talopram, 357 Tamoxifen, 127 Tandamine, 347, 460 Tazolol, 110, 268 Teclozan, 28 Temazepam, 402 Terodiline, 56 Tesicam, 379 Tesimide, 296 Testolactone, 160 Tetrahydropyrimidine synthesis, 303 Tetrahydroquinoline synthesis, 371 Tetrazole synthesis, 301,... 

Tebbe reaction 148 Tetracyclin synthesis 190 Tetrazole synthesis 17 Tetrodotoxin synthesis 136 Tocopherol synthesis 142 Tonantzitlolone synthesis 188 Triazine synthesis 17 Triclavulone synthesis 102... 

Scheme 15.8 (a) Polystyrene resin functionalization with carboxylic acids (b) substituted tetrazole synthesis on solid phase. 

Scheme 18 Three-step one-pot procedure for tetrazole synthesis on a polymer support...

Tetrazole synthesis tiom azides by dipolar cycloaddRion with activaled nRnles or intramoiocularly with nitriles m the presence of acids. 

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