From Saturated BN Compounds to Isoelectronic BN/CC Counterparts: An Insight from Computational Perspective

Abstract

In the present study, the inorganic analogues of alkanes as well as their isoelectronic BN/CC counterparts that bridge the gap between organic and inorganic chemistry are comparatively studied on the grounds of static DFT and Car-Parrinello molecular dynamics simulations. The BN/CC butanes CH3 CH2 BH2 NH3 , BH3 CH2 NH2 CH3 , and NH3 CH2 BH2 CH3 were considered and compared with their isoelectronic counterparts NH3 BH2 NH2 BH3 and CH3 CH2 CH2 CH3 . In addition, systematical replacement of the NH2 BH2 fragment by the isoelectronic CH2 CH2 moiety is studied in the molecules H3 N(NH2 BH2 )3-m (CH2 CH2 )m BH3 (for m=0, 1, 2, or 3) and H3 N(NH2 BH2 )2-m (CH2 CH2 )m BH3 (for m=0, 1, or 2). The DFT and Car-Parrinello simulations show that the isosteres of the BN/CC butanes CH3 CH2 BH2 NH3 , BH3 CH2 NH2 CH3 , and NH3 CH2 BH2 CH3 and of larger oligomers of the type (BN)k (CC)l where k≥l are stable compounds. The BN/CC butane H3 NCH2 CH2 BH3 spontaneously produces molecular hydrogen at room temperature. The reaction, prompted by very strong dihydrogen bonding NH⋅⋅⋅HB, undergoes through the neutral, hypervalent, pentacoordinated boron dihydrogen complex RBH2 (H2 ) [R=(CH2 CH2 )n NH2 ]. The calculations suggest that such intermediate and the other BN/CC butanes CH3 CH2 BH2 NH3 , BH3 CH2 NH2 CH3 , and NH3 CH2 BH2 CH3 as well as larger BN/CC oligomers are viable experimentally. A simple recipe for the synthesis of CH3 CH2 BH2 NH3 is proposed. The strength of the dihydrogen bonding appeared to be crucial for the overall stability of the saturated BN/CC derivatives.

N‐Thiophosphorylthioureas RNHC(S)NHP(S)(OiPr)2 as an Excellent Platform for Studying the Synergy between Hydrogen‐Hydrogen Bonding and Other Families of Non‐Covalent Interactions

“…Further, quite unintuitive at first glance anion ··· π interactions have been found to be crucial for not only for crystal engineering, but also for reactions in condensed phases . Later, it became clear that even polar hydrogen‐hydrogen bonds X–H δ + ··· – δ H–Y (X ≠ Y) can constitute a real gluing force in supramolecular chemistry …”

Non-Covalent Interactions in Hydrogen Storage Materials LiN(CH3)2BH3 and KN(CH3)2BH3

“…It has been demonstrated that the former feature of ammonia borane crystal originates predominantly from the existence of polar dihydrogen bonds N-H δ`¨¨¨´δ H-B between monomers [11][12][13][14][15][16]. Furthermore, it has been proven that the presence of N-H δ`¨¨¨´δ H-B as well as other non-covalent interactions not only determines the stability, but it can also facilitate various steps of dehydrogenation [5][6][7][8][11][12][13][14][15][16][17][18][19][20][21][22][23].…”

Structural versatility of the quasi-aromatic Möbius type zinc(ii)-pseudohalide complexes – experimental and theoretical investigations

“…In 2, the cation is a doubly charged centrosymmetric dinuclear structure with two Zn II [57][58][59][60][61] study, that the seven-membered rings in 1-3 constitute a quasi-aromatic Möbius-type motif, though the absolute magnitude of such p-delocalization is notably weaker than in the corresponding cadmium-based analogs. 24,27 Bulkiness of the ligands (L) are found not only to amplify London dispersion stabilization, 24,27,[40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56] but also inuence the magnitude of quasi-p-delocalization (of Möbius-type) through modi-cation of the polarity of Zn-L bonding.…”

“…The prevalence of the DE disp term is consistent with recent ndings, which rediscover the importance of London dispersion forces in small and sizeable species. 24,27,[40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56] In 3 the [Zn(NCS) 4 ] 2À anion sticks very strongly (DE int ¼ À193.21 kcal mol À1 ) to two neighboring stacked [Zn(NCS)L II ] + units primarily through electrostatic forces (75.3% of the overall stabilization) (Fig. 5).…”

“…7). It demonstrates the two-folded role of bulky substituents: they are not only dispersion donors, [40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56] but they also lead to amplication of the 7-MR twist (and enhanced quasiaromaticity). Previously only the former feature has been recognized.…”