Abstract: By X-ray diffraction analysis and IR spectroscopy, it was established here that vinyl carbocations C3H5+/C4H7+ with carborane counterion CHB11Cl11− form stable monosolvates C3H5+⋅C3H6/C4H7+⋅C4H8 with molecules of alkenes C3H6/C4H8. They contain molecular group =C+⋯Hδ−–Cδ+= with a new type of bond formed by the H atom of the H–C= group of the alkene with the C atom of the C+=C group of the carbocation. The short C+----Cδ+ distance, equal to 2.44 Å, is typical of that of X----X in proton disolvates (L2H+) with an quasi-symmetrical X–H+⋯X moiety (where X = O or N) of basic molecule L. The nature of the discovered bond differs from that of the classic H–bond by an distribution of electron density: the electron–excessive Hδ− atom from the (=)C–H group of the alkene is attached to the C+ atom of the carbocation, on which the positive charge is predominantly concentrated. Therefore, it can be called an inverse hydrogen bond.

Cite: Stoyanov E.S. , Bagryanskaya I.Y. , Stoyanova I.V.
A new type of C+⋯Hδ−(C=) bond in adducts of vinyl carbocations with alkenes
Scientific Reports. 2024. V.14. N1. 8818 :1-8. DOI: 10.1038/s41598-024-58109-4 Scopus

Dates:

Submitted:	Dec 19, 2023
Accepted:	Mar 25, 2024
Published online:	Apr 10, 2024
Published print:	Dec 1, 2024

Identifiers:

Scopus	2-s2.0-85189992855
OpenAlex	W4394693789

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