Thermodynamics and Mechanism of a Photocatalyzed Stereoselective [2 + 2] Cycloaddition on a CdSe Quantum Dot

Leighton O. Jones, Martín A. Mosquera, Yishu Jiang, Emily A. Weiss*, George C. Schatz, Mark A. Ratner

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

11 Scopus citations


Colloidal quantum dots (QDs) have shown promise over the last few decades for a range of applications including single photon emission, in vivo imaging, and photocatalysis. Recent experiments demonstrated that QDs impart stereoselectivity to triplet excited-state [2 + 2] cycloaddition reactions of alkenes photocatalyzed by the QD through self-assembly of the reagent molecules on the QD surface, but these experiments did not reveal the precise geometries of surface-bound molecules or their interactions with surface atoms. Here, a theoretical mechanistic approach is used to study such interactions for [2 + 2] cycloadditions of 4-vinylbenzoic acid derivatives on CdSe QDs. Spin-polarized periodic density functional theory (DFT) and nonperiodic DFT calculations are deployed to determine the origin of the selectivity for the syn diastereomer of the resultant tetrasubstituted cyclobutane product via atomistic modeling of the CdSe surface and substrates, determination of the thermodynamic energies of reactions for each step, the intermolecular interactions between the substrates, and the triplet state reaction paths. The calculations indicate that reaction selectivity arises from preferred binding of pairs through intermolecular interactions of substrate molecules on the QD surface in a syn-precursor structure followed by dimerization after triplet excitation. These mechanisms are generalizable to other metal-enriched QD surfaces that have a similar surface structure as that of CdSe, such as InSe or CdTe. Design principles for anti diastereomer derivatives are also discussed.

Original languageEnglish (US)
Pages (from-to)15488-15495
Number of pages8
JournalJournal of the American Chemical Society
Issue number36
StatePublished - Sep 9 2020

ASJC Scopus subject areas

  • Catalysis
  • Chemistry(all)
  • Biochemistry
  • Colloid and Surface Chemistry


Dive into the research topics of 'Thermodynamics and Mechanism of a Photocatalyzed Stereoselective [2 + 2] Cycloaddition on a CdSe Quantum Dot'. Together they form a unique fingerprint.

Cite this