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Experimental investigation of halogen-bond hard-soft acid-base complementarity.

ABSTRACT: The halogen bond (XB) is a topical noncovalent interaction of rapidly increasing importance. The XB employs a `soft' donor atom in comparison to the `hard' proton of the hydrogen bond (HB). This difference has led to the hypothesis that XBs can form more favorable interactions with `soft' bases than HBs. While computational studies have supported this suggestion, solution and solid-state data are lacking. Here, XB soft-soft complementarity is investigated with a bidentate receptor that shows similar associations with neutral carbonyls and heavy chalcogen analogs. The solution speciation and XB soft-soft complementarity is supported by four crystal structures containing neutral and anionic soft Lewis bases.

SUBMITTER: Riel AM

PROVIDER: S-EPMC6688566 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Experimental investigation of halogen-bond hard-soft acid-base complementarity.

Riel Asia Marie S AM Jessop Morly J MJ Decato Daniel A DA Massena Casey J CJ Nascimento Vinicius R VR Berryman Orion B OB

Acta crystallographica Section B, Structural science, crystal engineering and materials 20170329 Pt 2

The halogen bond (XB) is a topical noncovalent interaction of rapidly increasing importance. The XB employs a `soft' donor atom in comparison to the `hard' proton of the hydrogen bond (HB). This difference has led to the hypothesis that XBs can form more favorable interactions with `soft' bases than HBs. While computational studies have supported this suggestion, solution and solid-state data are lacking. Here, XB soft-soft complementarity is investigated with a bidentate receptor that shows sim ...[more]

PMID: 28362283

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