7227-92-1Relevant articles and documents
Alternative method for the synthesis of triazenes from aryl diazonium salts
Abrams
, (2021/05/10)
An alternative mild method for access to 1-aryl-3,3-dimethyl alkyl triazenes is described. This protocol employs the dropwise addition of a methanolic solution of a carboxylate (RCO2M) or carbonate (CO32?) to a gently heated DMF solution containing an aryl diazonium salt (ArN2+), that had been previously isolated. Presumably homolysis of the weak N–O bond of diazo ether adducts formed in this operation initiates radical pathways that lead to the generation of triazene product. DMF serves as not only a one-electron donor to the diazonium salts employed in this process, but also as a source of dimethylamine radicals that act as a nucleophilic coupling partner. The reaction provides modest yields (ca. 20–40%) across an array of aryl diazonium salts that contain various substitution. Furthermore this unique approach to triazenes contrasts with traditional methods that employ dimethyl amine in reagent form which directly couples with diazonium salts. Seemingly, only one other example employing somewhat similar reaction conditions to this current investigation en route to triazenes has been reported, albeit with lower yields and for one representative example furnished as a side-product. The current work here improves upon the efficiency of this reported result, and further expands the reaction scope.
Diazo reactions with unsaturated compounds: XII. Reaction of 1-(p-Carboxybenzenesulfonyl)-1,3-butadiene with aryldiazonium chlorides, 1-aryl-3,3-dimethyl-1-triazenes, and aryldiazonium tetrachlorocuprates(II)
Smalius,Naidan
, p. 586 - 588 (2008/02/11)
1-(p-Carboxybenzenesulfonyl)-1,3-butadiene reacts in aqueous acetone with aryldiazonium chlorides and 1-aryl-3,3-dimethyl-1-triazenes in the presence of copper(II) chloride and with tetrachlorocuprates(II) to form 1-(p-carboxybenzenesulfonyl)-4-aryl-3-chloro-1-butenes. Nauka/Interperiodica 2007.
1-Aryl-3,3-dialkyltriazenes: A convenient synthesis from dry arenediazonium o-benzenedisulfonimides - A high yield break down to the starting dry salts and efficient conversions to aryl iodides, bromides and chlorides
Barbero,Degani,Diulgheroff,Dughera,Fochi
, p. 2180 - 2190 (2007/10/03)
This research comprises three parts. The first part regards the synthesis of 1-aryl-3,3-dialkyltriazenes 3 by reaction of dry arenediazonium o-benzenedisulfonimides 1, also coming from weakly basic aromatic amines with dimethylamine or diethylamine in aqueous solution at 0-5 °C. Yields were usually greater than 90% and there was the possibility of recovering the o-benzenedisulfonimide (5), which could be reused to prepare the salts 1. In the second part it was demonstrated that there is the possibility of reconverting the triazenes 3 into the starting stable dry salts 1 by using 5 as acid. The reactions were carried out in glacial acetic acid at 50-55 °C and normally afforded salts 1 in yields of around 90-99%. The third part concerns the setting up of two procedures for the conversion of 3 to aryl iodides 9, bromides 10 and chlorides 11. Procedure A used the corresponding aqueous hydrogen halides in acetonitrile at r.t. or 60 °C, sometimes in the presence of aqueous HBF4, sometimes Cu powder (25 examples, yields 65%-88%). Procedure B usually used anhydrous methanesulfonic acid and tetraalkylammonium halides in anhydrous acetonitrile at temperatures varying from r.t. to 80 °C, sometimes in the presence of Cu (16 examples, yields 65-88%).
