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Abstract We report hydroboration of carbodiimide and isocyanate substrates catalyzed by a cyclic carbodiphosphorane catalyst. The cyclic carbodiphosphorane outperformed the other Lewis basic carbon species tested, including other zerovalent carbon compounds, phosphorus ylides, anN‐heterocyclic carbene, and anN‐heterocyclic olefin. Hydroborations of seven carbodiimides and nine isocyanates were performed at room temperature to formN‐boryl formamidine andN‐boryl formamide products. Intermolecular competition experiments demonstrated the selective hydroboration of alkyl isocyanates over carbodiimide and ketone substrates. DFT calculations support a proposed mechanism involving activation of pinacolborane by the carbodiphosphorane catalyst, followed by hydride transfer and B−N bond formation. 

Abstract Aerosol particles are important for our global climate, but the mechanisms and especially the relative importance of various vapors for new particles formation (NPF) remain uncertain. Quantum chemical (QC) studies on organic enhanced nucleation has for the past couple of decades attracted immense attention, but very little remains known about the exact organic compounds that potentially are important for NPF. Here we comprehensively review the QC literature on atmospheric cluster formation involving organic compounds. We outline the potential cluster systems that should be further investigated. Cluster formation involving complex multi‐functional organic accretion products warrant further investigations, but such systems are out of reach with currently applied methodologies. We suggest a “cluster of functional groups” approach to address this issue, which will allow for the identification of the potential structure of organic compounds that are involved in atmospheric NPF. This article is categorized under:Theoretical and Physical Chemistry > Reaction Dynamics and KineticsSoftware > Quantum ChemistryTheoretical and Physical Chemistry > ThermochemistryMolecular and Statistical Mechanics > Molecular Interactions 

The title compound, [Al 4 (CH 3 ) 8 (C 2 H 7 N) 2 H 2 ], crystallizes as eight-membered rings with –(CH 3 ) 2 Al–(CH 3 ) 2 N–(CH 3 ) 2 Al– moieties connected by single hydride bridges. In the X-ray structure, the ring has a chair conformation, with the hydride H atoms being close to the plane through the four Al atoms. An optimized structure was also calculated by all-electron density functional theory (DFT) methods, which agrees with the X-ray structure but gives a somewhat different geometry for the hydride bridge. Charges on the individual atoms were determined by valence shell occupancy refinements using MoPro and also by DFT calculations analyzed by several different methods. All methods agree in assigning a positive charge to the Al atoms, negative charges to the C, N, and hydride H atoms, and small positive charges to the methyl H atoms. 

The support vector machine model produced the best results with a root mean square error of 1.54 × 10⁻⁶K⁻¹. The model was applied to 3 593 726 possible AA′BB′O₃compositions, resulting in 150 451 predictions in the model confidence region.