Related Experiment Video
Updated: May 11, 2026
Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Superalkali character of alkali-monocyclic (pseudo)oxocarbon clusters
1State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, PR China.
Abstract:
A series of polynuclear superalkali cations C3X3Li3(+), C3(NCN)3Li3(+), C3X(NCN)2Li3(+), C3[C(CN)2]3Li3(+), C3(NCN)[C(CN)2]2Li3(+), C3X[C(CN)2]2Li3(+) (X = O, S, Se) and their corresponding neutral species were investigated by using the density functional theory. Except for C3Se3Li3, the ionization potentials for the studied neutral species are in the range of 2.52-3.75 eV, which are lower than the ionization potential of Cs atom (3.89 eV). For C3Se3Li3, although it has larger IP value of 4.51 eV than 3.89 eV of Cs, it is still less than IP = 5.39 eV of Li atom. Hence, they can be classified as superalkalies. In addition, the calculated results also indicated that besides the hyperlithiated configuration and segregated configuration, the excess electron may fully delocalize over various atoms (both center and ligands) in superalkalies. The present investigation gives hints to scientists that the search to a superatom can be extended by using more complicated cyclic (pseudo)oxocarbons as the central core of polynuclear superalkalies.
Related Concept Videos
03:06Alkali Metals
Table 1: Properties of the alkali metals
02:38Electrophilic Addition to Alkynes: Halogenation
Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.
01:04Structures of Aldehydes and Ketones
In aldehydes (Figures 1a and 1b), the carbonyl...
02:10Carbocations
02:47Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation
One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.
02:45Alkyl Halides
Alkyl halides are halogen-substituted alkanes wherein one or more hydrogen atoms of an alkane is replaced by a halogen atom such as fluorine, chlorine, bromine, or iodine. The carbon atom in an alkyl halide is bonded to the halogen atom, which is sp3-hybridized and exhibits a tetrahedral shape.
Unlike alkyl halides, compounds in which a halogen atom is bonded to an sp2 -hybridized carbon atom of a carbon-carbon double bond (C=C) are called vinyl halides. Whereas aryl...