Centropentaindan: synthesis and some bridgehead transformations of a novel regular centropolyindan

Kuck D, Schuster A, Gestmann D. Centropentaindan: synthesis and some bridgehead transformations of a novel regular centropolyindan. Journal of the Chemical Society, Chemical Communications. 1994;5(5):609-610.The synthesis of a novel centropentacyclic hydrocarbon, centropentaindan 1, has been achieved by fourfold bromination of the readily available difuso-triindan 4 followed by AlBr3-catalysed condensation with two molecules of benzene; functionalization of the two remaining tertiary bridgehead positions of 1 gives the strained, labile dibromide 6, which has been converted into the dimethyl derivative 7, the centrohexacyclic endoperoxide 8, and, again by AlBr3-catalysed condensation with benzene, into centrohexaindan 2

Driver reactions on ecological feedback via different HMI modalities

Nowadays there already exists a large amount of driving-related information displayed in the dashboard and thus additional information concerning ecological driving might enlarge the workload of the driver further. This raises the question whether the presentation of additional ecologic information via the haptic channel is more efficient and comfortable for the driver compared to a visual presentation. Previous studies proved the impact of driver feedback systems on the reduction of fuel consumption. However, most of the studies only dealt with visual displays. Thus in the present study a visual, a haptic, and a visual-haptic interface were designed for an acceleration and a gear shift advice system. Subsequently their impact on the acceleration and the gear shift behavior of the driver as well as their subjective acceptance were compared. Results showed that especially the combination of the visual and haptic modality led to the fastest reaction times and smallest deviations from the optimal acceleration and gear shift behavior. However, concerning the acceptance participants preferred the visual display

Fast interannular proton transfer in gaseous protonated [alpha, omega]-diphenylalkanes: stereocontrol by the cyclohexane-1,4-diyl unit

Kuck D, Thölmann D, Grützmacher H-F. Fast interannular proton transfer in gaseous protonated [alpha, omega]-diphenylalkanes: stereocontrol by the cyclohexane-1,4-diyl unit. Journal of the Chemical Society, Perkin Transactions 2, Physical Organic Chemistry. 1990;1990(2):251-256.The fast ring-to-ring proton transfer in protonated 1,4-bis(-phenylalkyl)cyclohexanes [(5a)+ H]+, [(5b+ H)]+, and [(6)+ H]+ has been studied by chemical ionization mass spectrometry. The cyclohexane-1,4-diyl unit exerts a distinct stereocontrol upon the rate of proton exchange. Complete proton equilibration is found for protonated cis-dibenzylcyclohexane [(5a)+ H]+, whereas in the trans isomer [(5b)+ H]+ the interannular proton transfer is strongly decelerated. The trans-bis(- phenylethyl) homologue [(6)+ H]+ is found to represent an intermediate case. By comparison with simpler protonated diphenylalkanes the rate of the interannular proton transfer for metastable ions [(5b)+ H]+ and [(6)+ H]+ is estimated to lie within the limits 5 × 105 and 106s–1

Benzoannelated centropolyquinanes. Part 21. Centrohexaindane: three complementary syntheses of the highest member of the centropolyindane family

Kuck D, Schuster A, Paisdor B, Gestmann D. Benzoannelated centropolyquinanes. Part 21. Centrohexaindane: three complementary syntheses of the highest member of the centropolyindane family. Journal of the Chemical Society, Perkin Transactions 1, Organic and Bio-Organic Chemistry. 1995;6(6):721-732.The syntheses of centrohexaindane 1, a unique hydrocarbon bearing six mutually fused indane units in a centrohexacyclic, Td symmetrical, and topologically nonplanar framework is reported in full detail. Three independent and complementary synthetic routes have been developed making use of derivatives of the readily accessible centrotriindanes 9, 10 and 11(R = CH3) and centrotetraindane 13(fenestrindane). The most efficient synthesis gives the title compound 1 in seven steps starting from indane-1,3-dione 15 in 40% yield, involving the broken fenestrane 10(broken-fenestrane route). Also starting from dione 15, an even shorter route furnishes our target molecule 1 in six steps via triptindanetrione 24 in 25% yield (propellane route). Both of these routes surpass our first synthesis reported in 1 988 via fenestrindane 13 which comprises eleven steps and gives a 7.5% overall yield from indanedione 15(fenestrane route). The three routes allow the six benzene rings of compound 1 to be introduced in complementary ways, thus promising the synthesis of centrohexaindane derivatives with various substitution patterns. Particularly remarkable key steps of the syntheses of compound 1 are, inter alia: (i) single and two-fold condensation of benzene by AlBr3-catalysed Friedel–Crafts reaction of cyclic 1,3-dibromides, (ii) unusual three-fold addition of phenyllithium to a 1,3,3-triketone (compound 24), (iii) two-fold and even three-fold cyclodehydration. Finally, a low-yield formation of compound 1, among other products, has been observed upon cyclodehydrogenation of 10-methyl-1,4,7-triphenyltribenzotriquinacene 32, which is obtained in two steps from 10-methyltribenzotriquinacene 11(R = Me), with Pd/C at 500 °C. The spectroscopic properties of compound 1 are presented along with some unique structural features of its rigid centrohexacyclic framework

User acceptance of an eco-driving support system

In this study an eco-driving support system was evaluated within a driving simulator study. The presented system was able to communicate with traffic lights and to detect traffic signs. On the basis of this information the system gave recommendations to the participants concerning fuel efficient gear shifting and acceleration/deceleration behavior. 30 participants drove different scenarios (traffic light approach, curves, and stop signs) with and without the eco-driving support system. Thereafter they answered acceptance questionnaires based on the Technology Acceptance Model concerning the system. Overall the acceptance of the system was very well. Yet, for some participants in the stop sign and curve scenarios the intervention of the system was too early

Polycyclic compounds beyond the propellanes and fenestranes: [mnopqr]centropenta- and [mnopqr]centrohexacyclanes

Kuck D, Krause RA, Gestmann D, Posteher F, Schuster A. Polycyclic compounds beyond the propellanes and fenestranes: [mnopqr]centropenta- and [mnopqr]centrohexacyclanes. TETRAHEDRON. 1998;54(20):5247-5258.Several new homo-and heterocyclic topologically nonplanar organic compounds(11, 14, 17-20) with centrohexacyclic (K-5 type) molecular frameworks are described. Besides some centrohexaquinanes comprising five-membered rings exclusively ('[5.5.5.5.5.5]centrohexacyclanes'), a number of congeners containing two six or two seven-membered rings have been synthesized for the first time ('[6.5.6.5.5.5]- and [7.5.7.5.5.5]centrohexacyclanes'). Based on [m.n.o.p]fenestranes, a notation is proposed to define unequivocally the mutual orientation of the various rings. (C) 1998 Elsevier Science Ltd. All rights reserved