Regiospecific nucleophilic substitution in 2,3,4,5,6-pentafluorobiphenyl as model compound for supramolecular systems. Theoretical study of transition states and energy profiles, evidence for tetrahedral S(N)2 mechanism

Kvicala, J; Benes, M; Paleta, O; Kral, V

HERO ID

3859241

Reference Type

Journal Article

Year

2010

Language

English

HERO ID 3859241
In Press No
Year 2010
Title Regiospecific nucleophilic substitution in 2,3,4,5,6-pentafluorobiphenyl as model compound for supramolecular systems. Theoretical study of transition states and energy profiles, evidence for tetrahedral S(N)2 mechanism
Authors Kvicala, J; Benes, M; Paleta, O; Kral, V
Journal Journal of Fluorine Chemistry
Volume 131
Issue 12
Page Numbers 1327-1337
Abstract 2,3,4,5,6-Pentafluorobiphenyl (PFBi) was modified by the nucleophilic substitution of one fluorine using a series of 0-, S- and N-nucleophiles, viz, alkaline salts of 2,2,2-trifluoro-ethanol, 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctanol, 1,2:3,4-di-O-isopropylidenexylitol, allylsulfane, 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctane-1-thiol, 3-aminopropan-1-ol (7), and tert-butyl N-(3-aminopropyl)carbamate (8). All the substitutions took place exclusively at the position para to the phenyl group. (3-Amino-propyl)amino derivative of PFBi (15) was further modified at the terminal amino group by acylation or fluoroalkylation. The reaction of 8 was applied to meso-5,10,15,20-tetrakis-(pentafluorophenyl)porphyrin (20) to afford tris- (21) and tetrakis-substituted (22) products with complete para-regioselectivity. Theoretical studies of the reaction pathways of PFBi with ammonia, microsolvated lithium fluoride or lithium hydroxide revealed that no Meisenheimer-type intermediates are formed in the course of the simulated reactions: instead, tetrahedral S(N)2 mechanism was found. Significant regioselectivity of the nucleophilic aromatic substitution, leading to 4-substituted products, was predicted based on relative transition state energies in agreement with the observed experimental results. (C) 2010 Elsevier BM. All rights reserved.
Doi 10.1016/j.jfluchem.2010.09.003
Wosid WOS:000285899700008
Is Certified Translation No
Dupe Override No
Comments Scopus URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-78649630220&doi=10.1016%2fj.jfluchem.2010.09.003&partnerID=40&md5=990aae1bc1757a9266cfd5c5e838fdfc
Is Public Yes
Language Text English
Keyword 2,3,4,5,6-Pentafluorobiphenyl; meso-5,10,15,20-Tetrakis-(pentafluorophenyl)-porphyrin; Nucleophilic substitution; Computational chemistry; Meisenheimer complex; Tetrahedral S(N)2 mechanism