1,2,3‐ and 1,2,4‐triazolium salts, pyrazoles, and quinoxalines from diarylnitrilimines and isocyanides: A study of the scope

Abstract

For Abstract see ChemInform Abstract in Full Text.

Gold(I) Complexes with “Normal” 1,2,3-Triazolylidene Ligands: Synthesis and Catalytic Properties

“…For metal complex synthesis, methyl- and cyclohexyl-substituted normal triazolium chlorides were selected as precursors. They were prepared according to routes described earlier by Moderhack and co-workers, providing access a large variety of these salts . After the successful synthesis of Rh and Ir complexes by applying an in situ silver carbene generation reaction protocol, the corresponding Au compounds were prepared analogously (Scheme ).…”

Four-membered rings from isocyanides: Developments since the mid 1980s

“…Nitrile imines: Detailed studies on the behavior of N-aryl nitrile imines towards isocyanides [28][29][30][31][32] have shown that the title reaction occurred under certain conditions. 29,31,32 Best suited are nitrile imines bearing a donor-substituted phenyl group at the terminal nitrogen like 34, they gave cycloadducts 36 with a wide variety of isocyanides (Scheme 8).…”

“…29,31,32 Best suited are nitrile imines bearing a donor-substituted phenyl group at the terminal nitrogen like 34, they gave cycloadducts 36 with a wide variety of isocyanides (Scheme 8). 31,32 These four-membered rings, however, eluded isolation, but their formation could be inferred from products formed by [2+2] cycloreversion into benzonitrile and a carbodiimide (37), by ring expansion to a quinoxaline (38), and finally by [2+2] cycloreversion of the secondary adduct 39 into 37 and a 1,2,4-triazole (40). Besides these compounds products such as 41-45 were found; formally, they derive from the linear adduct 35 which in the case R = t-Bu could be detected spectroscopically.…”

“…33 Compared to 34, the proclivity of its N-phenyl analog to undergo a [1+3] cycloaddition is low, 29 and with Ar = 4-NO 2 C 6 H 4 there were no indications at all. 32 This failure applies also to nitrile imines having an acceptor group at the C-terminus like an acyl 31 or a 4-nitrophenyl substituent. Azomethine imines: In contrast to the aryl functionalized CNN moiety in 46a which, using tertbutyl isocyanide, was earlier cyclized to a 1,2-diazetidine ring (47), 2 the acyl group in the congener 46b, as shown recently, confers upon the molecule a 1,5-dipolar character which led to the formation of a 1,3,4-oxadiazine cycle (48) (Scheme 9).…”

Synthesis, Crystal Structure, Thermal Behavior and Sensitivity of [Mn(AZT)₂(H₂O)₄] (HTNR)₂·4H₂O

“…HydroxylOatomsandtriazolylringNatomshavegoodcoor鄄 dinationcapacities.Therefore,1,2,4鄄triazolehaspotentialbridg鄄 ingfashions(滋 1,2 , 滋 2,4 ,and 滋 1,2,4 )andstrongcoordinationcapabili鄄 tiestobridgetransitionmetalions [18] .Tothebestofourknowl鄄 edgeinpublishedstudieson1,2,4鄄triazole鄄basedenergeticcom鄄 plexes,theligandshavebeenlimitedto1,2,4鄄triazol鄄5鄄one [19][20] ,3鄄 nitro鄄1,2,4鄄triazol鄄5鄄one [21][22][23][24] ,and4鄄 amino鄄1,2,4鄄triazol鄄5鄄one [25] . Thusfar,theligandsofothertriazolederivatives,suchas3鄄amino鄄 1H鄄1,2,4鄄triazole [26] and3,4,5鄄triamino鄄1,2,4鄄triazole [27] ,havebeen brieflystudied.ForthecompoundofAZT,mainattentionhas beenfocusedonitsenergeticionicsalts [28][29][30][31][32] ,exceptforourearly researchofusingAZTasligandsforzinc(II)andcadmium(II) cations,wherethestructureandthermalpropertieswereinvesti鄄 gated [33][34] .…”