The effect of boron substitution on cyclacenes

Türker, Burhan Lemi
Azizoglu, A
AM1-type semiempirical molecular orbital treatment was performed on the Huckel-type cyclacenes having certain number of boron atoms at the peri-positions and at the fusion sites of the arenoid rings. The effect of boron atoms is generally destabilizing in all the cases as compared to their unsubstituted cyclacene counterparts. The AM1 results revealed that certain properties of the boron-substituted cyclacenes are affected not only by the number of arenoid rings they have but also by the nature of their peripheral circuits.


The effect of para-cyclophane structure on cyclacenes
Türker, Burhan Lemi (2000-02-01)
Semiempirical molecular orbital treatment at the level of AMI type has been performed on the Huckel type cyclacenes having the normal and the skew type para-cyclophane moiety embedded into their structures. The cyclophane effect is found to be operative on the lower members by veiling the cryptoannulenic effect which is influential on the heats of formation values and the frontier molecular orbital energies of the higher members as well as the parent cyclacenes.
An investigation of the interaction of 4-membered rings with adjacent carbanion centers
Guven, OO; Peynircioğlu, Nihad Bekir (2002-01-01)
A series of cyclobutylcarbinyl phenyl ketones was prepared and the rates of base catalyzed hydrogen-deuterium exchange of a-hydrogen atoms were compared with those of appropriate model compounds, to test the validity of an earlier finding, which suggested that a four-membered ring, like the three-membered ring, has the ability to stabilize an adjacent carbanion center. In this study, unlike the cyclopropyl group, no clearly defined stabilization of the adjacent, carbanion center was detected by the 1-phenyl...
Production of boron nitride by carbothermic and mechanochemical methods, and nanotube formation
Camurlu, HE; Aydogdu, A; Topkaya, Yavuz Ali; Sevinc, N (2003-09-12)
The formation of hexagonal boron nitride by carbothermic reduction of boron oxide and nitridation has been examined. Experiments were conducted in the temperature range of 1100-1500degreesC for durations between 15-240 minutes. Products were examined by X-ray, SEM and chemical analysis. The results showed that the reaction proceeds through a gaseous boron containing species, which is most probably 13203(g). It was found that all of the carbon was consumed and formation of boron nitride was complete in 2 hou...
A theoretical study on the strong codimer of C-60 and Si-60, C58Si58
Türker, Burhan Lemi (2001-07-09)
The strong codimer Of C-60 and Si-60 that is C58Si58 is considered for AM1 type semiempirical molecular orbital treatment at the, restricted Hartree-Fock level. The results reveal that C58Si58 structure should be highly endothermic but a stable molecule. The structure is expected to have some nonlinear properties.
Flame retardancy effects of zinc borate and nanoclay in ABS, and boron compounds in PET
Özkaraca, Ayşe Çağıl; Kaynak, Cevdet; Department of Metallurgical and Materials Engineering (2011)
In this thesis there were two main purposes, the first one being to investigate effects of zinc borate (ZB) on the flammability behavior of ABS when used with and without a traditional brominated flame retardant (BFR) / antimony trioxide (AO) system. The second purpose was to investigate contribution of nanoclays (NC) to the flame retardancy performance of the same traditional BFR compound with various combinations of AO and ZB again in ABS matrix. For these purposes, materials were melt compounded by using...
Citation Formats
B. L. Türker and A. Azizoglu, “The effect of boron substitution on cyclacenes,” JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM, pp. 151–157, 2001, Accessed: 00, 2020. [Online]. Available: