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The benzo annulated cycloheptatriene PCP pincer ruthenium hydrido dicarbonyl complex syn-2 was prepared in one step by treatment of the ligand 1 with Ru3(CO)12. Protonation of syn-2 with the superacid [H(Et2O)2][BArF24] {[BArF24]- = tetrakis[bis(trifluoromethyl)phenyl]borate} initiates the highly stereoselective hydrogenation of one of the double bonds in the cycloheptatriene backbone. This results in the formation of the pentacoordinate cationic 16-electron dicarbonyl ruthenium complex 3. Hydrogenation of 3 with LiAlH4 generates the hydride complexes syn-4 and anti-4 which after protonation allow isolation of the symmetric 5. In 5 a second double bond of the cycloheptatriene backbone was hydrogenated. Complex 5 was also obtained directly by the reaction of 3 with hydrogen (1 bar). Storage of 5 under a hydrogen atmosphere yields two pairs of η2-H2 complexes (syn-7, anti-7) which are in a tautomeric equilibrium with their corresponding dihydrides (syn-8, anti-8). A stepwise transfer of the hydrides to the ligand backbone can be deduced from the distribution of deuterium along the seven membered ring after applying the deuterated reagents (D+, D2). The observed stereochemistry suggests that the hydride transfer is controlled by conformational constraints.

Exercise-induced asthma (EIA) is very common in children with asthma. For this reason they avoid every strenuous exercise because they fear a new asthma attack. Working capacity and maturation of motor performance can be insufficient as a consequence. We investigated whether a special training programme in an asthma sports group has positive effects not only on asthma, but also on working capacity and motor performance. 11 children with extrinsic asthma (4 girls, 7 boys), 8 to 14 years old, were studied before and after a 6-month out-patient rehabilitative sports therapy (sports group) with regard to their degree of bronchial hyperreactivity (BHR), frequency of EIA, cardiopulmonary capacity for exercise; knowledge about their asthma, level of coordination and condition, and their movement-related anxiety. There were 9 children with extrinsic asthma (2 girls, 7 boys), 8 to 15 years old, in a control group. They did not take part in any special training programme. After the sports therapy we found in 3 children of the sports group a decrease in BHR, EIA was now present in only 2 of formerly 4 children. Physical working capacity (PWC) at the aerobic/anaerobic threshold improved in the sports group by about 1 W/kg body weight (p = 0.008), efficiency of work from 23.7% to 27.9% (p = 0.009). We also found a remarkable improvement of motor abilities. Movement-related anxiety decreased in the sports group both in Indoor sports (p = 0.0089) and aquatics (p = 0.026). In the control group there was no significant change. Physical training in children with asthma has many positive effects on lung function and motor performance. We believe that the limit for an EIA release is shifted to a higher PWC. The reduction of the anxiety over sports at a higher level of PWC contributes to an improved quality of life for children with asthma.