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Abstract Ultra‐small nanoparticles of CeO₂obtained in molecular form, so‐called molecular nanoparticles, have been limited to date to a family whose largest member is of nuclearity Ce₄₀with a {Ce₄₀O₅₈} core atom count. Herein we report that a synthetic procedure has been developed to the cation [Ce₁₀₀O₁₄₉(OH)₁₈(O₂CPh)₆₀(PhCO₂H)₁₂(H₂O)₂₀]¹⁶⁺, a member with a much higher Ce₁₀₀nuclearity and a {Ce₁₀₀O₁₆₇} core that is more akin to the smallest ceria nanoparticles. Its crystal structure reveals it to possess a 2.4 nm size and high D_2dsymmetry, and it has also allowed identification of core surface features including facet composition, the presence and location of Ce³⁺and H⁺(i.e. HO⁻) ions, and the binding modes of the ligand monolayer of benzoate, benzoic acid, and water ligands. 

Abstract Ultra‐small nanoparticles of CeO₂obtained in molecular form, so‐called molecular nanoparticles, have been limited to date to a family whose largest member is of nuclearity Ce₄₀with a {Ce₄₀O₅₈} core atom count. Herein we report that a synthetic procedure has been developed to the cation [Ce₁₀₀O₁₄₉(OH)₁₈(O₂CPh)₆₀(PhCO₂H)₁₂(H₂O)₂₀]¹⁶⁺, a member with a much higher Ce₁₀₀nuclearity and a {Ce₁₀₀O₁₆₇} core that is more akin to the smallest ceria nanoparticles. Its crystal structure reveals it to possess a 2.4 nm size and high D_2dsymmetry, and it has also allowed identification of core surface features including facet composition, the presence and location of Ce³⁺and H⁺(i.e. HO⁻) ions, and the binding modes of the ligand monolayer of benzoate, benzoic acid, and water ligands. 

Abstract Reported here is the synthesis and self‐assembly characterization of [n.n]paracyclophanes ([n.n]pCps,n=2, 3) equipped with anilide hydrogen bonding units. These molecules differ from previous self‐assembling [n.n]paracyclophanes ([n.n]pCps) in the connectivity of their amide hydrogen bonding units (C‐centered/carboxamide vs.N‐centered/anilide). This subtle change results in a ≈30‐fold increase in the elongation constant for the[2.2]pCp‐4,7,12,15‐tetraanilide ([2.2]pCpNTA) compared to previously reported[2.2]pCp‐4,7,12,15‐tetracarboxamide ([2.2]pCpTA), and a ≈300‐fold increase in the elongation constant for the[3.3]pCp‐5,8,14,17‐tetraanilide ([3.3]pCpNTA) compared to previously reported[3.3]pCp‐5,8,14,17‐tetracarboxamide ([3.3]pCpTA). The[n.n]pCpNTAmonomers also represent the reversal of a previously reported trend in solution‐phase assembly strength when comparing[2.2]pCpTAand[3.3]pCpTAmonomers. The origins of the assembly differences are geometric changes in the association between[n.n]pCpNTAmonomers—revealed by computations and X‐ray crystallography—resulting in a more favorable slipped stacking of the intermolecular π‐surfaces ([n.n]pCpNTAvs.[n.n]pCpTA), and a more complementary H‐bonding geometry ([3.3]pCpNTAvs.[2.2]pCpNTA). 

Abstract Acyclic ketone‐derived oxocarbenium ions are involved as intermediates in numerous reactions that provide valuable products, however, they have thus far eluded efforts aimed at asymmetric catalysis. We report that a readily accessible chiral carboxylic acid catalyst exerts control over asymmetric cyclizations of acyclic ketone‐derived trisubstituted oxocarbenium ions, thereby providing access to highly enantioenriched dihydropyran products containing a tetrasubstituted stereogenic center. The high acidity of the carboxylic acid catalyst, which exceeds that of the well‐known chiral phosphoric acid catalyst TRIP, is largely derived from stabilization of the carboxylate conjugate base through intramolecular anion‐binding to a thiourea site. 

Reported are the consequences and complexities associated with installation of hydrogen-bonding functionality at the interior of π-conjugated oligomers to promote self-assembly in solution and morphological control in thin films. 

Combining strain-promoted azide–alkyne cycloaddition (SPAAC) and inorganic click (iClick) reactivity provides access to metal 1,2,3-triazolates. Experimental and computational insights demonstrate that iClick reactivity of the tested metal azides (LM-N 3 , M = Au, W, Re, Ru and Pt) depends on the accessibility of the azide functionality rather than electronic effects imparted by the metal. SPAAC iClick reactivity with cyclooctyne is observed when the azide functionality is sterically unencumbered, e.g. [Au(N 3 )(PPh 3 )] (Au–N3), [W(η 3 -allyl)(N 3 )(bpy)(CO) 2 ] (W–N3), and [Re(N 3 )(bpy)(CO) 3 ] [bpy = 2,2′-bipyridine] (Re–N3). Increased steric bulk and/or preequilibria with high activation barriers prevent SPAAC iClick reactivity for the complexes [Ru(N 3 )(Tp)(PPh 3 ) 2 ] [Tp = tris(pyrazolyl)borate] (Ru–N3), [Pt(N 3 )(CH 3 )(P i Pr 3 ) 2 ] [ i Pr = isopropyl] (Pt(II)–N3), and [Pt(N 3 )(CH 3 ) 3 ] 4 ((PtN3)4). Based on these computational insights, the SPAAC iClick reactivity of [Pt(N 3 )(CH 3 ) 3 (P(CH 3 ) 3 ) 2 ] (Pt(IV)–N3) was successfully predicted. 

Bimetallic bis-urea functionalized salen-aluminum catalysts have been developed for cyclic carbonate synthesis from epoxides and CO2. The urea moiety provides a bimetallic scaffold through hydrogen bonding, which expedites the cyclic carbonate formation reaction under mild reaction conditions. The turnover frequency (TOF) of the bis-urea salen Al catalyst is three times higher than that of a μ-oxo-bridged catalyst, and 13 times higher than that of a monomeric salen aluminum catalyst. The bimetallic reaction pathway is suggested based on urea additive studies and kinetic studies. Additionally, the X-ray crystal structure of a bis-urea salen Ni complex supports the self-assembly of the bis-urea salen metal complex through hydrogen bonding.