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1.
Chem Commun (Camb) ; 60(36): 4858-4859, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38605667

RESUMO

Correction for 'Not antiaromaticity gain, but increased asynchronicity enhances the Diels-Alder reactivity of tropone' by Eveline H. Tiekink et al., Chem. Commun., 2023, 59, 3703-3706, https://doi.org/10.1039/D3CC00512G.

2.
Phys Chem Chem Phys ; 26(11): 9073, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38436412

RESUMO

Correction for 'Pericyclic reaction benchmarks: hierarchical computations targeting CCSDT(Q)/CBS and analysis of DFT performance' by Pascal Vermeeren et al., Phys. Chem. Chem. Phys., 2022, 24, 18028-18042, https://doi.org/10.1039/D2CP02234F.

3.
Chem Sci ; 15(5): 1648-1656, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38303946

RESUMO

We have quantum chemically investigated the nature and stability of C-C and Si-Si bonds in R3A-AR3 (A = C, Si; R3 = H3, Me3, Me2Ph, MePh2, Ph3, t-Bu3) using density functional theory (DFT). Systematic increase of steric bulk of the substituents R has opposite effects on C-C and Si-Si bonds: the former becomes weaker whereas the latter becomes stronger. Only upon going further, from R = Ph to the bulkiest R = t-Bu, the R3Si-SiR3 bond begins to weaken. Our bonding analyses show how different behavior upon increasing the steric bulk of the substituents stems from the interplay of (Pauli) repulsive and (dispersion) attractive steric mechanisms. Extension of our analyses to other model systems shows that C-Si bonds display behavior that is in between that of C-C and Si-Si bonds. Further increasing the size of the group-14 atoms from C-C and Si-Si to Ge-Ge, Sn-Sn and Pb-Pb leads to a further decrease in the sensitivity of the bond strength with respect to the substituents' bulkiness. Our findings can be used as design principles for tuning A-A and A-A' bond strengths.

4.
Angew Chem Int Ed Engl ; 63(13): e202316021, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38143241

RESUMO

An enantioselective cobalt-catalyzed C(sp3 )-H alkenylation of thioamides with but-2-ynoate ester coupling partners employing thioamide directing groups is presented. The method is operationally simple and requires only mild reaction conditions, while providing alkenylated products as single regioisomers in excellent yields (up to 85 %) and high enantiomeric excess [up to 91 : 9 enantiomeric ratio (er), or up to >99 : 1 er after a single recrystallization]. Diverse downstream derivatizations of the products are demonstrated, delivering a range of enantioenriched constructs. Extensive computational studies using density functional theory provide insight into the detailed reaction mechanism, origin of enantiocontrol, and the unusual regioselectivity of the alkenylation reaction.

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