MaxPHOS is an active and robust P-stereogenic ligand for asymmetric catalysis. The presence of an À NH À bridge between the two phosphine moieties allows the NH/PH tautomerism to take place. The neutral ligand, in which the NH form predominates, is an air-sensitive compound. However, protonation of MaxPHOS leads to the stable PH form of the ligand, in which the overall positive charge is distributed on both P centers. This protonation turns the MaxPHOS·HBF 4 salt 3 into an airstable compound both in the solid state and in solution.The salt 3 is also a convenient precursor for the preparation of rhodium(I) complexes by direct ligand exchange with the complexFinally, the corresponding rhodium(I)-MaxPHOS complex was tested in the asymmetric hydrogenation of a wide range of substrates. The complex proved to be a highly selective and robust system in these reactions.

Aims Cells limit the cell number of dense biofilms by releasing self‐inhibitory molecules. Here, we aim to assess the effectiveness of yeast quorum sensing (QS) molecules and the antifungal agent natamycin against yeast biofilms of strains commonly isolated from fruit juice ultrafiltration membranes. Methods and Results Yeast QS molecules, such as tyrosol, 2‐phenylethanol and farnesol, were detected by solvent extraction and HS‐SPME GC‐MS in Candida tropicalis cultures. The effect of QS molecules on mono‐ and multispecies biofilms formed by Rhodotorula mucilaginosa, C. tropicalis, Candida krusei and Candida kefyr was evaluated by plate count and epifluorescence microscopy. Farnesol caused a decrease in cell number and disrupted mono‐ and multispecies yeast biofilms during adhesion (0·6 mmol l−1). 2‐phenyl ethanol 1·2 mmol l−1 stimulated biofilm density and increased cell number in both mono‐ and multispecies biofilms, while tyrosol did not show effects when tested against C. tropicalis biofilms (0·05–1·2 mmol l−1). Natamycin caused a strong decrease in cell number and disruption of biofilm structure in C. tropicalis biofilms at high concentrations (0·3–1·2 mmol l−1). The combination of farnesol 0·6 mmol l−1 and natamycin at 0·01 mmol l−1, the maximum concentration of natamycin accepted for direct addition into fruit juices, effectively reduced cell counts and disrupted the structure of C. tropicalis biofilms. Conclusion Farnesol 0·6 mmol l−1 significantly increased the inhibition exerted by natamycin 0·01 mmol l−1 (~5 ppm) reducing biofilm development from juice on stainless steel surfaces. Significance and Impact of the Study These results support the use of QS molecules as biofilm inhibitors in beverages and would certainly inspire the design of novel preservative and cleaning products for the food industry based on combinatory approaches.

Visually impaired or blind students require adjustments to the traditional hands-on activities and methodological and didactic strategies employed by the teacher. These adaptations are based on multisensory teaching tools, which reinforce the learning of all students in general. This paper presents simple teaching resources that allow students with visual disabilities to solve problems of Organic Chemistry independently and on an equal footing with their nondisabled peers.