A Theoretical Prediction of Potentially Observable Lithium Compounds with Planar Tetracoordinate Carbons

Abstract

Several potentially experimentally accessible lithiated heterocyclic and heteroatom compounds with planar tetracoordinate carbons (ptC) have been predicted computationally. These utilize the strong electron-donating ability and the bridging proclivity of lithium to achieve the ptC preferences. As the p orbitals on the central carbons are only partially occupied, their electronic structures are similar to those of the related carbenes, e.g. imidazole-2-ylidene, rather than to the other ptC compounds such as dilithiocyclopropane.

Theoretical study on a family of organic molecules with planar tetracoordinate carbon

“…The NICS(0) value of C 3 B 2 H 2 (CHOH) 2 is À18.01, while the other's NICS(0) values are between À25.65 and À31.65. Therefore, these three-membered rings have strong aromaticities, which are consistent with the previous studies [15,25]. The calculated WBIs of C 3 B 2 H 4 and its 11 derivatives are listed in Table 4.…”

“…Similarly, the delocalized ptCcontaining molecules composed of C, B, H atoms were also extensively studied [14][15][16][17][18][19][20][21][22][23][24][25][26]. The smallest organic molecule C 3 B 2 H 4 with ptC, proposed by Minyaev et al [18], can be served as a basic block to build an extended system such as the stable beltlike compounds (C 3 B 2 ) n H 4 (n = 2-6) and tubular compounds (C 3 B 2 ) n [25,31].…”

Four Decades of the Chemistry of Planar Hypercoordinate Compounds

“…[87a] Remarkably,e ven larger all-boron clusters, including quasiplanar structures,n amely chiral B 30 À [91] and B 35 À [92] with adouble-hexagonal vacancy ( Figure 42) as well as aplanar hexagonal B 36 À [93] (Figure 43), have been detected in the gas-phase and characterized by photoelectron spectroscopy and ab initio calculations. À,2À , [81] B 9 À , [81] B 10 ,B 11 À ,a nd B 12 [90] can be viewed as analogues of benzene on the basis of their six p electrons, because they have p-molecular orbital patterns similar to those of benzene.Aperfectly planar B 16 2À (D 2h ) [94] with 10 p electrons can be considered an all-boron naphthalene.A lso, three neutral boron clusters B 11 ,B 16 ,a nd B 17 are shown to have planar or quasi-planar structures by vibrational spectroscopy and ab initio calculations.…”

Recent advances in planar tetracoordinate carbon chemistry

“…Using Hoffmann's strategy (also called the electronic approach), several ptC molecules have been proposed in silico 14,[18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37] and/or experimentally detected. [38][39][40][41][42][43][44][45][46][47][48] A few realized compounds of nonclassical structures containing ptCs are shown in Figure 2.…”