Short X···N Halogen Bonds With Hexamethylenetetraamine as the Acceptor
Anyfanti, Goulielmina; Bauzá, Antonio; Gentiluomo, Lorenzo; Rodrigues, João; Portalone, Gustavo; Frontera, Antonio; Rissanen, Kari; Puttreddy, Rakesh (2021)
Anyfanti, Goulielmina
Bauzá, Antonio
Gentiluomo, Lorenzo
Rodrigues, João
Portalone, Gustavo
Frontera, Antonio
Rissanen, Kari
Puttreddy, Rakesh
2021
623595
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:tuni-202106075720
https://urn.fi/URN:NBN:fi:tuni-202106075720
Kuvaus
Peer reviewed
Tiivistelmä
Hexamethylenetetramine (HMTA) and N-haloimides form two types of short (imide)X···N and X–X···N (X = Br, I) halogen bonds. Nucleophilic substitution or ligand-exchange reaction on the peripheral X of X–X···N with the chloride of N-chlorosuccinimide lead to Cl–X···N halogen-bonded complexes. The 1:1 complexation of HMTA and ICl manifests the shortest I···N halogen bond [2.272(5) Å] yet reported for an HMTA acceptor. Two halogen-bonded organic frameworks are prepared using 1:4 molar ratio of HMTA and N-bromosuccinimide, each with a distinct channel shape, one possessing oval and the other square grid. The variations in channel shapes are due to tridentate and tetradentate (imide)Br···N coordination modes of HMTA. Density Functional Theory (DFT) studies are performed to gain insights into (imide)X···N interaction strengths (ΔEint). The calculated ΔEint values for (imide)Br···N (−11.2 to −12.5 kcal/mol) are smaller than the values for (imide)I···N (−8.4 to −29.0 kcal/mol). The DFT additivity analysis of (imide)Br···N motifs demonstrates Br···N interaction strength gradually decreasing from 1:1 to 1:3 HMTA:N-bromosuccinimide complexes. Exceptionally similar charge density values ρ(r) for N–I covalent bond and I···N non-covalent bond of a (saccharin)N–I···N motif signify the covalent character for I···N halogen bonding.
Kokoelmat
- TUNICRIS-julkaisut [16944]