As appreciation for nonclassical hydrogen bonds has progressively increased, so have efforts to characterize these interesting interactions. Whereas several kinds of C−H hydrogen bonds have been well‐studied, much less is known about the R3N+−C−H⋅⋅⋅X variety. Herein, we present crystallographic and spectroscopic evidence for the existence of these interactions, with special relevance to Selectfluor chemistry. Of particular note is the propensity for Lewis bases to engage in nonclassical hydrogen bonding over halogen bonding with the electrophilic F atom of Selectfluor. Further, the first examples of1H NMR experiments detailing R3N+−C−H⋅⋅⋅X (X=O, N) hydrogen bonds are described.
C( sp 2 )−H Hydrogen‐Bond Donor Groups in Chiral Small‐Molecule Organocatalysts
Asymmetric catalysis of chemical transformations by chiral small organic molecules has become an important approach in organic synthesis. Attractive noncovalent interactions such as N(O)−H hydrogen‐bonding, π‐stacking, and cation‐π interactions have been exploited as the primary and/or secondary function(s) of the catalysts, but C(
- NSF-PAR ID:
- 10103210
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Asian Journal of Organic Chemistry
- Volume:
- 8
- Issue:
- 8
- ISSN:
- 2193-5807
- Page Range / eLocation ID:
- p. 1306-1316
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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