Anionic triazine systems

Abstract

The synthesis of TAS+ C3N3F4- (1) (TAS+ = (Me2N)3S+) and the reactions of 1 with Me3SiOSiMe3 and Me3SiCF3 to give TAS+ C3N3F2O- (2) and TAS+[(NCF)(NCCF3)(NC(CF3)(2)]- (4) are reported. An isomer of 4, TAS+[(NCCF3)2(NCFCF3)]-, compound 6, was obtained by fluoride ion addition to (CF3CN)3. From the reactions with Me3SiNMe2 neutral fluoroamino triazines C3N3Fn(NMe2)(n-1) (n = 1, 2) were isolated. Possible reaction pathways are discussed, the X-ray structures of 1, 2, 4 and 6 were determined.

Fluoride ion transfer and stabilisation of reactive ions

“…Fluoride ion addition to triazines might be regarded as model reaction for a nucleophilic attack at these systems; the resulting fluoro anions correspond to the transition states (Scheme 12 [75,76] In thiatriazines the carbon is attacked exclusively; if no carbon is present, ring cleavage is observed with TAS þ NSF 2 À being formed (Scheme 13 [75,77]). …”

Fluorinated Triazines

“…3 , 4 , 5 and 6 ) [ 4 ]. It has been shown that values of the C 1 -N 1 and C 1 -N 3 bonds in the anion C 3 N 3 F 4 − correspond to those Valency angles: N 1 -C 1 -N 3 123.…”

Synthesis, Characterization, and Crystal Structure of a Triazine Anion Pentafluoroosmium(VI) Complex

“…These C-N bond distances and angles are slightly different compared to those of the free anionic C 3 N 3 F 4 − [26]. The difference in some distances of C-N and C-F bonds, shown in Table 2, might be attributed to the fact that the reported anion [26] is a free anion crystallized with another counter cation which allows the complete delocalization of the charge over the anion, while the anion in the title compound is bonded through one N atom with Os(VI) and consequently affects the delocalization of the charge over the anion. This is also evident by the different planarity of the reported anion C 3 N 3 F 4 − ring as compared to the bonded one (this work).…”

“…Kingston et al [26] reported the synthesis of the same anion using a different strategy, and the product was characterized spectroscopically and by X-ray structural analysis. Therefore, our method represents a new strategy for the formation of this anion which forms the foundation for the synthesis of other anionic triazine species.…”

“…Those bonded to the tetrahedral C1 are longer than those bonded to the planar sp 2 carbons (C2 and C3; Table 2). This fact makes this anion susceptible to selective substitution (weak C1-F bonds), and this has been used to synthesize the substituted triazine anions [26]. …”