title: Orthohalogen substituents dramatically enhance hydrogen bonding of aromatic ureas in solution.
abstract: The phenylurea moiety is a ubiquitous synthon in supramolecular chemistry. Here we report that the introduction of chlorine or bromine atoms in the ortho positions to the urea unit is a simple and very efficient way to improve its intermolecular hydrogen bond (HB) donor character. This effect was demonstrated in solution both in the context of self-association of bis-ureas and hydrogen bonding of mono-ureas to strong HB acceptors.
authors.affiliation: Dipartimento di Chimica and IMC-CNR, Università La Sapienza, 00185 Roma, Italy.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Giannicchi
authors.forename: Benjamin
authors.initials: B
authors.lastname: Jouvelet
authors.forename: Benjamin
authors.initials: B
authors.lastname: Isare
authors.forename: Mathieu
authors.initials: M
authors.lastname: Linares
authors.forename: Antonella
authors.initials: A
authors.lastname: Dalla Cort
authors.forename: Laurent
authors.initials: L
authors.lastname: Bouteiller