Orthohalogen substituents dramatically enhance hydrogen bonding of aromatic ureas in solution.
نویسندگان
چکیده
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.
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ورودعنوان ژورنال:
- Chemical communications
دوره 50 5 شماره
صفحات -
تاریخ انتشار 2014