Structure and Bonding of Tetracyanopyrrolides

Abstract

Salts bearing the tetracyanopyrrolide anion (TCP) were synthesized from tetracyano‐1,4‐dithiin and sodium azide according to a modified synthetic protocol. The solid‐state structures of HTCP, MeTCP, Me4NTCP, NaTCP, and the ionic liquid EMIMTCP (EMIM = 1‐ethyl‐3‐methylimidazolium) are discussed for the first time. According to experimental and computational data, the TCP anion can be regarded as a pseudohalide with π bonds highly delocalized over the entire anion including the four cyano groups. The planar anion is C2v symmetric and represents a multifunctional binary CN ligand, which is capable of forming classic coordination bonds through the lone pairs of the CN groups or the ring nitrogen atom. In addition, noncovalent interactions such as π–π interactions are found and can be used to strengthen structural and electronic communication between organic ligands.

Synthesis and Reactivity of a Bio‐inspired Dithiolene Ligand and its Mo Oxo Complex

“…Peaks at m / z =549 (corresponding to [ 16 +H] + ) in the former case (Supporting Information, Figure S8) and m / z =485 (corresponding to [ 15 +H] + ) in the latter (Supporting Information, Figure S9) were observed. This mechanism is comparable to that previously reported for the air oxidation of disodium dimercaptomaleodinitrile (Na 2 mnt) giving tetracyano‐1,4‐dithiin as the product . To the best of our knowledge, it is the first time that the air oxidation product of a Mo IV (dithiolene) 2 complex was structurally characterized.…”

“…This mechanism is comparable to that previously reportedf or the air oxidation of disodium dimercaptomaleodinitrile (Na 2 mnt) giving tetracyano-1,4-dithiin as the product. [15] To the best of our knowledge,i ti st he first time that the air oxidation product of aM o IV (dithiolene) 2 complex was structurally characterized.…”

Tetrakis(2‐cyanoethoxy)borate – An Alternative to Tetracyanidoborate‐Based Ionic Liquids

“…[7] We have recently studied the synthesis and properties of CN-functionalized borate/aluminate based ILs with anions of the type [E(O-C 6 X 4 -CN) 4 ] -(E = B, Al; X = H, F) [8] and tetracyanopyrrolide-based ILs. [9] Tetraphenoxyaluminates and -borates [10,11] and their fluorinated analogues [12] have been studied and widely applied, for example, in catalysis; however, to the best of our knowledge cyano-substituted anions of the type [B(O-C n H 2n -CN) 4 ] -(n = 2, 3, etc.) with alkyl chains are not known yet.…”

Arsenic‐Mediated C−C Coupling of Cyanides Leading to Cyanido Arsazolide [AsC4N4]−

“…[25][26][27] Interestingly Finally,D FT,N BO, and NRT computations at the pbe/aug-ccpvdz level (see the Supporting Information, DFT = density functional theory,N BO = natural bond theory,N RT = natural resonance theory) were carriedo ut to shed light into the bonding and formation of [AsC 4 N 4 ] À .S olvent effects, which are essential to stabilize charged ions, are incorporated using the integral equationf ormalism version of the polarizablec ontinuum model (PCM, solvent = acetonitrile). [28] Finally,w ew ant to answer the question how [AsC 4 N 4 ] À is formed from itss tructurali somer [As(CN) 4 ] À (2), which can be assumedt ob ef ormed in the first reaction step when As(CN) 3 (1)i st reated with CN À (Scheme 5). TheL UMO and HOMO are strongly localized on the arsenic atom.…”