Journal article

Publication year: 2009

Pages: 5153-5161

Journal: European Journal of Organic Chemistry

Volume number: 2009

Issue number: 30

DOI Link: https://doi.org/10.1002/ejoc.200900600

Publisher: Wiley

Abstract: 

The photoacetylation of diamondoids (nanodiamonds), in particular
[1212]pentamantane, [1(2,3)4]pentamantane, and [123]tetramantane, with
diacetyl almost exclusively gives apical acetyl derivatives. The
mechanism of the photoacetylation was studied on the basis of a
comparative analysis of the experimental deuterium kinetic isotope
effects as well as the observed C–H bond substitution selectivities,
which were also computed at the B3LYP, B3PW91, and MP2 levels of theory
including polarized continuum modeling of solvent effects. The high
apical C–H bond selectivities in the photoacetylation of diamondoids are
determined by the higher polarizabilities of the cages along the apical
direction in the transition structures for hydrogen abstraction with
the triplet diacetyl diradical. Steric effects play only a minor role,
and in combination with solvation, outweigh charge‐transfer effects that
usually favor medial substitution with electrophiles and electrophilic
radicals.

Harvard Citation style: Fokin, A., Gunchenko, P., Novikovsky, A., Shubina, T., Chernyaev, B., Dahl, J., et al. (2009) Photoacetylation of Diamondoids: Selectivities and Mechanism, European Journal of Organic Chemistry, 2009(30), pp. 5153-5161. https://doi.org/10.1002/ejoc.200900600

APA Citation style: Fokin, A., Gunchenko, P., Novikovsky, A., Shubina, T., Chernyaev, B., Dahl, J., Carlson, R., Yurchenko, A., & Schreiner, P. (2009). Photoacetylation of Diamondoids: Selectivities and Mechanism. European Journal of Organic Chemistry. 2009(30), 5153-5161. https://doi.org/10.1002/ejoc.200900600