Theoretical and Quantitative Structural Relationships of the Electron Transfer and Electrochemical Properties ofCis-Unsaturated Thiocrown Ethers and Supramolecular Complexes [X-UT-Y]@[La₂@C₇₂(Adamantylidene Mono-Adducts)_n] (n=0,1)

Abstract

Endohedral fullerenes belong to a new class of compounds that are technologically and scientifically important owing to their unique structures and optoelectronic properties. The isolated pentagon rule (IPR) states that all pentagonal carbon rings are isolated in the most stable fullerene. Metallofullerenes M@C n , are a class of spherical carbon allotrope group with unique properties. Electron transfer between metallofullerenes and other molecules is thought to involve the transfer of electrons between molecules surrounding the fullerene cage. One class of electron-transfer molecules is the [La 2 @C 72 (Adamantylidene MonoAdducts) n ] (n ¼ 0,1) 10-13. The supramolecular complexes 1-9 and 10-13 are shown to possess a previously unreported host-guest interaction for electron transfer processes. The unsaturated, cis-geometry, thiocrown ethers, (1-9), (described as [X-UT-Y], where X and Y indicate the numbers of carbon and sulfur atoms, respectively), are a group of crown ethers that display interesting physiochemical properties in light of their conformational restriction compared to a corresponding saturated system, as well as the sizes of their cavities. Topological indices have been successfully used to construct mathematical methods that relate structural data to various chemical and physical properties. To establish a good relationship between the structures of 1-9 with derivatives of 10-13, an index is utilized, m cs . This index is the ratio of the sum of the number of carbon atoms (n c ) and the number of sulfur atoms (n s ) with the product of these two numbers for 1-9. In this study, the relationships between this index and oxidation potential ( ox E 1 ) of 1-9, as well as the first and second free energies of electron transfer (DG et(n) , for n ¼ 1, 2, which is given by the Rehm-Weller equation) between 1-9 and [La 2 @C 72 (Adamantylidene MonoAdducts) n ] (n ¼ 0,1; n ¼ 0 for "a", n ¼ 1 for "b-g") 10-13 and their derivatives as [X-UT-Y]@[La 2 @C 72 (Adamantylidene Mono-Adducts) n ] (n ¼ 0,1; n ¼ 0 for "a", n ¼ 1 for "b-g") (groups 14-17 and their derivatives) supramolecular complexes are presented and investigated.

Free Energies of Electron Transfer, Electron Transfer Kinetic Theoretical and Quantitative Structural Relationships and Electrochemical Properties Studies of Gadolinium Nitride Cluster Fullerenes Gd3N@Cnin [X-UT-Y][Gd3N@Cn](n = 80, 82, 84, 86 and 88) Supramolecular Complexes

“…The ratio of the sum of the number of carbon atoms (n c ) and the number of sulfur atoms (n s ) to the product of these two numbers (μ cs ) is a useful numerical and structural value for the unsaturated thiocrown ethers 1-9 that were investigated (78,79,(89)(90)(91)(92)(93).…”

“…The use of effective mathematical methods in making strong correlations between chemical properties and the indices have been reported (83)(84)(85)(86)(87)(88)(89)(90), which is an important area of development. μ cs has defined by the ratio of the sum of the number of carbon atoms (n c ) and the number of sulfur atoms (n s ) with the product of these two items for 1-9 (89)(90)(91)(92)(93). This index was a useful numerical and structural value in the studies reported here on the unsaturated thiocrown ethers 1-9.…”

“…Quantitative structural relationships studies of the μ cs index with respect to the oxidation potentials ( ox E 1 ) of thiocrown ethers (1-9), as well as the free energy of electron Downloaded by [The University of British Columbia] at 04: 16 21 November 2014 transfer ( G et ) between 1-9 with fullerenes and some of the EMFs were previously reported (11,(89)(90)(91)(92)(93).…”

“…The Red E n (n = 1,2) data for 10-14 are presented inTable 2(11).The oxidation potentials ( ox E 1 ) of 4-7 were found to be 0.82, 0.79, 0.73 and 0.69 V, respectively [33,34,[85][86][87][88]. The free energies of electron transfer( G et(n) , n = 1,2) between 1-9 and 10-14 for making [X-UT-Y][Gd 3 N@C n ](n = 80, 82, 84, 86 and 88) 15a-i -19a-i were calculated using the Rehm-Weller equation(89)(90)(91)(92)(93)(94).…”