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This document is the Accepted Manuscript version of a Published Work that appeared in final form in Inorganic Chemistry", copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.inorgchem.1c02467. Platinum-based anticancer drugs are actively developed utilizing lipophilic ligands or drug carriers for the efficient penetration of biomembranes, reduction of side effects, and tumor targeting. We report the development of a supramolecular host–guest system built on cationic platinum(II) compounds bearing ligands anchored in the cavity of the macrocyclic host. The host–guest binding and hydrolysis process on the platinum core were investigated in detail by using NMR, MS, X-ray diffraction, and relativistic DFT calculations. The encapsulation process in cucurbit[7]uril unequivocally promotes the stability of hydrolyzed dicationic cis-[PtII(NH3)2(H2O)(NH2-R)]2+ compared to its trans isomer. Biological screening on the ovarian cancer lines A2780 and A2780/CP shows time-dependent toxicity. Notably, the reported complex and its β-cyclodextrin (β-CD) assembly achieve the same cellular uptake as cisplatin and cisplatin@β-CD, respectively, while maintaining a significantly lower toxicity profile.

1H NMR spectroscopy has become an important technique for the characterization of transition-metal hydride complexes, whose metal-bound hydrides are often difficult to locate by X-ray diffraction. In this regard, the accurate prediction of 1H NMR chemical shifts provides a useful, but challenging, strategy to help in the interpretation of the experimental spectra. In this work, we establish a density-functional-theory protocol that includes relativistic, solvent, and dynamic effects at a high level of theory, allowing us to report an accurate and reliable interpretation of 1H NMR hydride chemical shifts of iridium polyhydride complexes. In particular, we have studied in detail the hydride chemical shifts of the [Ir6(IMe)8(CO)2H14]2+ complex in order to validate previous assignments. The computed 1H NMR chemical shifts are strongly dependent on the relativistic treatment, the choice of the DFT exchange–correlation functional, and the conformational dynamics. By combining a fully relativistic four-component electronic-structure treatment with ab initio molecular dynamics, we were able to reliably model both the terminal and bridging hydride chemical shifts and to show that two NMR hydride signals were inversely assigned in the experiment., A new strategy by computational 1H NMR spectroscopy was used to predict and support the characterization of complex metal polyhydrides. A density-functional-theory protocol including relativistic, solvent, and dynamic effects at a high level of theory was established for the [Ir6(IMe)8(CO)2H14]2+ complex. The combination of a relativistic four-component electronic-structure treatment with ab initio molecular dynamics provided a means to accurately model both terminal and bridging hydride shifts, showing that two signals were inversely assigned in the NMR experiment.

The incarceration of o‐benzyne and 27 other guest molecules within hemicarcerand 1, as reported experimentally by Warmuth, and Cram and co‐workers, respectively, has been studied by density functional theory (DFT). 1H‐NMR chemical shifts, rotational mobility and conformational preference of the guests within the supramolecular cage were determined, which showed intriguing correlations of the chemical shifts with structural parameters of the host‐guest system. Furthermore, based on the computed chemical shifts reassignments of some NMR signals are proposed. This affects in particular the putative characterization of the volatile benzyne molecule inside a hemicarcerand, for which our CCSD(T) and KT2 results indicate that the experimentally observed signals are most likely not resulting from an isolated benzyne within the supramolecular host. Instead, we show that the guest reacted with an aromatic ring of the host, and this adduct is responsible for the experimentally observed signals The following organizations are thanked for financial support: MICINN (PhD-scholarship ACC CTQ2011-25086/BQU, projects CTQ2014-59212-P, CTQ2015-70851-ERC, CTQ2017-87392-P), CONACyT project 2014-383560, GenCat (PhD scholarship ARR 2015_FI_B_00165, 2014SGR1202 and XRQTC network) and European Fund for Regional Development (FEDER, UNGI10-4E-801)

We report a combined experimental-theoretical study on the 31P NMR chemical shift for a number of trans-platinum(ii) complexes. Validity and reliability of the 31P NMR chemical shift calculations are examined by comparing with the experimental data. A successful computational protocol for the accurate prediction of the 31P NMR chemical shifts was established for trans-[PtCl2(dma)PPh3] (dma = dimethylamine) complexes. The reliability of the computed values is shown to be critically dependent on the level of relativistic effects (two-component vs. four component), choice of density functionals, dynamical averaging, and solvation effects. Snapshots obtained from ab initio molecular dynamics simulations were used to identify those solvent molecules which show the largest interactions with the platinum complex, through inspection by using the non-covalent interaction program. We observe satisfactory accuracy from the full four-component matrix Dirac-Kohn-Sham method (mDKS) based on the Dirac-Coulomb Hamiltonian, in conjunction with the KT2 density functional, and dynamical averaging with explicit solvent molecules.

In the present study, we have theoretically analyzed supramolecular complexes based on the Watson-Crick A-T and A-U base pairs using dispersion-corrected density functional theory (DFT). Hydrogen atoms H8 and/or H6 in the natural adenine and thymine/uracil bases were replaced, respectively, by substituents X8, Y6 = NH - , NH 2 , NH 3 + (N series), O - , OH, OH 2 + (O series), F, Cl or Br (halogen series). We examined the effect of the substituents on the hydrogen-bond lengths, strength and bonding mechanism, and the NMR shielding constants of the C2-adenine and C2-thymine/uracil atoms in the base pairs. The general belief in the literature that there is a direct connection between changes in the hydrogen-bond strength and the C2-adenine shielding constant is conclusively rejected by our computations The following organizations are thanked for financial support: the Ministerio de Ciencia e Innovación (MICINN, PhD-scholarship BES-2012-052792), the Ministerio de Economía y Competitividad (MINECO, CTQ2014-59212-P and CTQ2015-70851-ERC), GenCat (2014SGR1202 and XRQTC network) and European Fund for Regional Development (FEDER, UNGI10-4E-801)

Can relativistic effects modify the NICS and the B(ind) values? In this manuscript we evaluate the relativistic corrections incorporated via the zeroth-order regular approximation to the calculations of nucleus-independent chemical shifts and the induced magnetic field (B(ind)) in the E12(2-) spherenes (E = Ge, Sn, Pb). We found that both electron delocalization descriptors are strongly affected by the relativistic corrections. For instance, for plumbaspherene, the difference in values from the nonrelativistic to the relativity-included calculation is almost 40 ppm! Our results show that the changes observed in the NICS and B(ind) values in the title cages are a consequence of the treatment of the relativistic effects. If these effects are included as scalar or spin-orbit calculations, then we can establish the next trend: Ge12(2-) is a nonaromatic species, Sn12(2-) is a low aromatic species, and Pb12(2-) is strongly aromatic, according to calculated NICS and B(ind) values. Thus, any prediction of electron delocalization in molecules containing heavy elements without considering an adequate treatment for relativistic effects may lead to an erroneous chemical interpretation.

Inverse carbon-free sandwich structures with formula E2P 4 (E=Al, Ga, In, Tl) have been proposed as a promising new target in main-group chemistry. Our computational exploration of their corresponding potential-energy surfaces at the S12h/TZ2P level shows that indeed stable carbon-free inverse-sandwiches can be obtained if one chooses an appropriate Group 13 element for E. The boron analogue B2P4 does not form the D4h-symmetric inverse-sandwich structure, but instead prefers a D2d structure of two perpendicular BP2 units with the formation of a double B-B bond. For the other elements of Group 13, Al-Tl, the most favorable isomer is the D4h inverse-sandwich structure. The preference for the D2d isomer for B2P 4 and D4h for their heavier analogues has been rationalized in terms of an isomerization-energy decomposition analysis, and further corroborated by determination of aromaticity of these species. Topsy turvy sandwiches: The possibility of the formation of inverse carbon-free sandwiches for clusters of type E2P4 with Group 13 elements B-Tl has been explored. This proposition is based on consideration of the aromaticity of the square-planar P4 2- unit, which should favor the formation of the cluster with a proper choice of the E + ions Moshinsky Foundation, SIP-IPN (Grants 20113309 and 20120968), and Conacyt (Grant INFRA-2012-01-188147) supported the work in Mexico. The CGSTIC (Xiuhcoalt) at Cinvestav is gratefully acknowledged for generous allocation of computational resources. Financial support from the Spanish MICINN (projects CTQ2011-23156/BQU and CTQ2011-25086/BQU), the FEDER fund (European Fund for Regional Development; grant UNGI08-4E-003), and the Generalitat de Catalunya (2009SGR637 and Xarxa de Referencia en Quimica Teorica i Computacional) is greatly acknowledged. E. M. acknowledges financial support of the EU under Marie Curie Career Integration grant (PCI09-GA-2011-294240) and the Beatriu de Pinos program from AGAUR for the postdoctoral grant (BP_B_00236). The authors are grateful to the Research Executive Agency of the European Research Council for financial support through the PIRSES-GA-2009-247671 project of the FP7-PEOPLE-2009-IRSES program. The authors thank Eloy Ramos for his helpful assistance with APOST-3D program

A series of clusters with the general formula CBe(5)E(-) (E = Al, Ga, In, Tl) are theoretically shown to have a planar pentacoordinate carbon atom. The structures show a simple and rigid topological framework-a planar EBe(4) ring surrounding a C center, with one of the ring Be-Be bonds capped in-plane by a fifth Be atom. The system is stabilized by a network of multicenter σ bonds in which the central C atom is the acceptor, and π systems as well by which the C atom donates charge to the Be and E atoms that encircle it.

We report here a systematic study on the ability of molecular cages to bind (transition) metals. Starting from the superferrocenophane we investigate the incorporation of first-row transition metal (Sc-Zn) and alkaline-earth metal (Mg, Ca) double cations into these supermetallocenophane (super[5]phane) cages, and compare them with the corresponding metallocenes (Inorg. Chim. Acta, 2007, 360, 179). Moreover, we also investigate the binding of neutral and double-cationic metals inside supermetallocyclophane (super[6]phane) cages. The heterolytic and homolytic associations show preferences for different metals, and new metal-containing cages are proposed that should be viable candidates for synthesis The following organizations are thanked for financial support: the Ministerio de Ciencia e Innovacion (MICINN, project number CTQ2011-25086/BQU), and the DIUE of the Generalitat de Catalunya (project number 2009SGR528). Financial support from MICINN (Ministry of Science and Innovation, Spain) and the FEDER fund (European Fund for Regional Development) was provided by grant UNGI08-4E-003. The authors are grateful to the Research Executive Agency of the European Research Council for financial support through the PIRSES-GA-2009-247671 project of the FP7-PEOPLE-2009-IRSES program. MPJ acknowledges support from the Ministerio de Ciencia e Innovacion (project JCI-2009-05953) and the Academy of Finland (project 136079). This work was supported in Guanajuato by Conacyt (Grant 57892); ACC thanks Conacyt for the Master fellowship

A series of three neutral, hexacoordinate tin(IV) complexes were synthesized by the reaction of 4,4'‐dimethyl‐2,2'‐bipyridine (DMB) with SnX4, X = Cl, Br, and I, as starting materials. The complexes (DMB)SnX4 were characterized in solution by 1H, 13C, and 119Sn NMR spectroscopy, and in the solid‐state by 119Sn MAS NMR spectroscopy. In addition, single‐crystal X‐ray diffraction and elemental analysis were used to confirm the molecular structures. In these complexes, the tin atom adopts a distorted octahedral arrangement and the DMB acts as a bidentate N,N'‐chelate ligand. Computational DFT methods were also employed to gain more insight into the nature of the bonding in these complexes, including the hypothetical complexes (DMB)SnX4 (X = F, At). Additionally, the validity and reliability of the 119Sn NMR chemical shifts were examined. The calculated values were compared with the experimental signals and the effects of structure and solvent are discussed. Finally, all of the complexes (DMB)SnX4 were successfully tested for the ring‐opening polymerization (ROP) of bulk ε‐caprolactone under non‐dried and aerobic conditions as precatalyst.

The transfer hydrogenation of N-heterocyclic carbene (NHC)-supported diborenes with dimethylamine borane proceeds with high selectivity for the trans-1,2-dihydrodiboranes. DFT calculations, supported by kinetic studies and deuteration experiments, suggest a stepwise proton-first-hydride-second reaction mechanism via an intermediate μ-hydrodiboronium dimethylaminoborate ion pair.