This work explores the self-disproportionation of enantiomers (SDE) of chiral amides via achiral, gravitydriven column chromatography as typically used in laboratory settings. The major findings of this work are: (1) the remarkable persistence and high magnitude of the SDE for the analytes under a variety of conditions, including polar solvents and different achiral stationary phases and (2) the notable generality of the SDE phenomenon as it occurs for a wide range of chiral amide substrates and even for a broad range of starting ee. This last aspect is unusual and not commonly observed. The key conclusion of this work is that it judiciously conveys the predictability of the SDE for chiral amides under the routine conditions of achiral chromatography. These results are consequently of concern for practitioners in the area of catalytic asymmetric synthesis involving chiral amides as intermediates or products and the inferents need to be taken extremely seriously by workers in the field.
If robot systems are being deployed in real world settings with untrained users who happen to accidentally pass by or could leave at any moment in time, then this places specific demands on the robot system: it needs to secure and maintain the user's engagement. In this, a common and critical problem consists of entering into a 'focused encounter'. It requires each interactional partner to closely react upon the other's actions on a very fine-grained level engaging in a stepwise and dynamic process of mutual adjustments. We report initial findings from a study in which we have developed a preliminary, simple solution to this problem inspired by work from Conversation Analysis [7]. Using this as an instrument to explore the impact of a 'contingent' (CE) vs. 'non-contingent entry' (NCE), we find that users who enter into the interaction in a dynamic and contingent manner show a significantly different way of interacting with the robot than the NCE group.
In this paper we consider the development of a museum guide robot that has both autonomous and remotely controlled features. We focus on the capabilities such a robot could have to help focus the attention of a visitor on an object or artefact. Inspired by studies of social interaction, which investigate whether the robot could deploy "restarts" and "pauses" at certain moments in its talk to first elicit the visitor's attention/gaze towards the robot. We report an experiment where we deployed such a robot to interact with real visitors to a science museum. These experiments show that such a strategy does seem to have a significant impact on obtaining the visitor's gaze.
Optically active atropisomeric N-(2,5-di-tert-butylphenyl)-1,2,3,4-tetrahydroquinoline with an N-C chiral axis was prepared via a catalytic enantioselective reaction. The addition of methane sulfonic acid to this axially chiral quinoline dramatically lowered the barrier to rotation around the chiral axis.
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