Various titanium(IV) complexes of the type Cp′Ti(OAr)Cl2 (Cp′ ) cyclopentadienyl; OAr ) aryloxy) could be prepared in high yields from Cp′TiCl3. Cp*Ti(O-2,6-i Pr2C6H3)Me2 (Cp* ) C5Me5) could also be prepared from Cp*TiMe3 with 2,6-i Pr2C6H3OH in high yield (77%). These complexes showed notable catalytic activities for ethylene polymerization with MAO or Al i Bu3-Ph3CB(C6F5)4: Cp*Ti(O-2,6-i Pr2C6H3)X2 [X ) Cl (2b), Me (8b), CF3SO3 (9b)] showed the highest activities among these complexes. The effects of substituents on both cyclopentadienyl (pentamethylcyclopentadienyl) and aryloxy (2,6diisopropylphenoxy) groups are important for the remarkable activity. The crystallographic analyses of CpTi(O-2,6-i Pr2C6H3)Cl2 (1b), Cp*Ti(O-2,6-i Pr2C6H3)Cl2 (2b), and (1,3-t Bu2C5H3)Ti(O-2,6-i Pr2C6H3)Cl2 (6b) could be performed, and the bond angle of Ti-O-C (phenyl group) for 2b (173.0°) was found to be significantly different from those for other complexes (162.3-163.1°), although no significant differences are observed for other bond lengths and angles among these compounds. CpTi(O-2,4,6-Me3C6H2)2Cl (7a) and CpTi(O-2,6-i Pr2C6H3)2Cl (7b) could be prepared from CpTiCl3 with the corresponding phenol under the refluxing conditions of toluene, and the structure of 7a could be determined by X-ray crystallography. These complexes also exhibited moderate catalytic activities for ethylene polymerization in the presence of MAO, which was prepared by removing toluene and an excess amount of AlMe3, and the effect of the bulk of phenoxy ligand on the activity was demonstrated. 2b was also found to be an effective catalyst precursor for ethylene/1-butene copolymerization, and the smaller rErB values (0.25-0.36) compared to [Me2Si(C5Me4)(N t Bu)]TiCl2 (2.45) were observed by microanalysis of the resultant copolymers.

Various titanium complexes of the type Cp′Ti-(OAr)Cl 2 (Cp′ ) cyclopentadienyl; OAr ) aryloxy) could be prepared in high yields from Cp′TiCl 3 . These complexes show remarkable catalytic activities for alkene polymerization with MAO or Al i Bu 3 -Ph 3 CB(C 6 F 5 ) 4 : (C 5 -Me 5 )Ti(O-2,6-i Pr 2 C 6 H 3 )X 2 (X ) Cl (2b), Me (8b), CF 3 -SO 3 (9b)) showed the highest activities. The bond angle Ti-O-C (phenyl group) in 2b (173.0°) is significantly different from those for other complexes (162.3-163.1°).

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Driving simulator usage is often accompanied by motion sickness, and techniques for its prevention are not yet established. To reduce visually induced motion sickness (VIMS), we investigated the effects of synchronised presentation of engine sounds and motorcycle vibration on VIMS. A total of 80 participants experienced a driving scene with a head-mounted display for 5 minutes with or without synchronised presentation of engine sound and vibration. The results showed that VIMS scores, as measured by the Fast Motion Sickness scale, were significantly lower in participants who experienced the driving scene with sounds and vibration than in those who experienced the scene with sounds only, vibration only, or neither. Multiple regression analyses revealed that susceptibility to VIMS consistently explained the severity of VIMS to some extent but not with perceived realism of the virtual reality (VR) scene, sex, and experiences about VR devices and vehicles. This study demonstrated that simultaneous presentation of engine sounds and vibration, which were synchronous to each other and tightly coupled with the visual flow speed, effectively reduces VIMS while experiencing motorcycling simulators. The findings not only improve practical knowledge for reducing VIMS in driving simulators but also provide evidence for understanding the mechanisms of VIMS.