Concerted halogen and hydrogen bonding in [RuI2(H2dcbpy)(CO)2]⋯I2⋯(CH3OH)⋯I2⋯[RuI2(H2dcbpy)(CO)2]

Abstract

A new type of concerted halogen bond-hydrogen bond interaction was found in the solid state structure of [RuI(2)(H(2)dcbpy)(CO)(2)]···I(2)···(MeOH)···I(2)···[RuI(2)(H(2)dcbpy)(CO)(2)]. The iodine atoms of the two I(2) molecules interact simultaneously with each other and with the OH group of methanol of crystallization. The interaction was characterized by single crystal X-ray measurements and by computational charge density analysis based on DFT calculations.

Alternative Motifs for Halogen Bonding

“…The components assemble through both hydrogen and halogen bonds with strong I–I ··· SCN halogen bonds (I ··· S distances of 2.84–3.53 Å, 7–25 % reduction; Figure 25, a) appearing to act independently of the hydrogen bonds. This contrasts the behaviour of another system reported by Haukka and co‐workers and ourselves in which a concerted hydrogen/halogen‐bonding motif was identified 80. An unusual Ru–I ··· I–I ··· I–I ··· I–Ru halogen‐bonded assembly links the complex [Ru(CO) 2 (2,2′‐bipyridyl‐4,4′‐dicarboxylato) 2 I 2 ] moieties into chains through two molecules of iodine by means of both Ru–I ··· I–I (3.14–3.24 Å, 21–18 % reduction) and I–I ··· I–I halogen bonds (3.54 Å, 11 % reduction).…”

Enhancement of Iodine–Hydride Interaction by Substitution and Cooperative Effects in NCX–NCI–HMY Complexes

“…Generally, the weaker interaction shows a larger increased percentage of the interaction energy due to another stronger interaction, which has been well documented in previous articles of the interplay between two different types of interactions. [25][26][27][28][29] Table 3 also lists the synergetic energy (E syn ), which has been widely used in the study of the interplay between two kinds of non-covalent interactions. [25][26][27][28][29] It is computed with formulas of E syn = DE total À(DE 1 +DE 2 ), where DE total is the total interaction energy in the trimer given in Table 2, while DE 1 and DE 2 are the interaction energies of the respective NCX-NCI and NCI-HMY dimers given in Table 1, respectively.…”

“…[25][26][27][28][29] Table 3 also lists the synergetic energy (E syn ), which has been widely used in the study of the interplay between two kinds of non-covalent interactions. [25][26][27][28][29] It is computed with formulas of E syn = DE total À(DE 1 +DE 2 ), where DE total is the total interaction energy in the trimer given in Table 2, while DE 1 and DE 2 are the interaction energies of the respective NCX-NCI and NCI-HMY dimers given in Table 1, respectively. As can be seen, the computed values of E syn are negative for all trimers, which indicates a positive cooperativity between both types of interactions and is in agreement with shortening of the binding distances.…”

“…Halogen bonding exhibits cooperative effect with itself and other types of interactions. [25][26][27][28][29][30][31][32][33][34][35][36][37] Such effect can regulate the strength of halogen bonding.…”

Neutral Organometallic Halogen Bond Acceptors: Halogen Bonding in Complexes of PCPPdX (X = Cl, Br, I) with Iodine (I2), 1,4-Diiodotetrafluorobenzene (F4DIBz), and 1,4-Diiodooctafluorobutane (F8DIBu)

“…14e−14n,15,16 Recently some of us have reported new Ru-based XB systems, one with the known solar-cell N3 dye molecule. 17,18 …”