73 research outputs found
Development of <i>C</i><sub>2</sub>âSymmetric Chiral Bifunctional Triamines: Synthesis and Application in Asymmetric Organocatalysis
The
synthesis and application of a newly designed <i>C</i><sub>2</sub>-symmetric chiral bifunctional triamine family (<i>C</i><sub>2</sub>-CBT) is reported. These enantiopure chiral
triamine scaffolds can be accessed in multigram amounts from simple
amino acids while avoiding chromatographic purification. As a proof
of principle, <i>C</i><sub>2</sub>-CBT has been studied
in the aldol reaction of cyclic ketones with isatins, with the target
tertiary alcohols being formed in a highly efficient manner. Catalyst
recovery by simple extraction techniques and subsequent reuse has
been performed
Number of PAU exams and exercises analysed.
<p>Number of PAU exams and exercises analysed.</p
Washback Effect of University Entrance exams in Applied Mathematics to Social Sciences
<div><p>Curricular issues of subject Applied Mathematics to Social Sciences are studied in relation to university entrance exams performed in several Spanish regions between 2009â2014. By using quantitative and qualitative analyses, it has been studied how these exams align with curriculum and how they produce a washback on curriculum and teachersâ work. Additionally, one questionnaire about teachersâ practices has been performed, in order to find out how the exams are influencing teaching methodology development. Main results obtained show that evaluation is producing a bias on the official curriculum, substantially simplifying the specific orientation that should guide applied mathematics. Furthermore, teachersâ practices are influenced by the exams, and they usually approach their teaching methodology to the frequent types of exams. Also, slight differences among the teachers lead to distinguish two behavioral subgroups. Results can also be useful in an international context, because of the importance of standardized exit exams in OECD countries.</p></div
Scalable Synthesis of the Amber Odorant 9-<i>epi</i>-Ambrox through a Biomimetic Cationic Cyclization/Nucleophilic Bromination Reaction
A novel biomimetic
nucleophilic bromocyclization reaction is used
in the key step of a new and straightforward synthesis of 9-<i>epi</i>-Ambrox, an organic compound of high interest and value
in the context of fragrances. This strategic reaction allows access
to 9-<i>epi</i>-Ambrox on a gram scale from a dienyne derivative,
easily available from geraniol, following a sequence of seven steps
(35% global yield) with just one purification process. Both enantiomers
of the molecule were obtained by a challenging enzymatic resolution
Algebra: Appearance percentage of CUâs.
<p>Algebra: Appearance percentage of CUâs.</p
Calculus: Appearance percentage of CUâs
<p>Calculus: Appearance percentage of CUâs</p
CUâs from Probability & Statistics block.
<p>CUâs from Probability & Statistics block.</p
Cluster analysis.
<p>Clusters plotted over the two main dimensions in scores (biggest points represent group average)</p
Obtained p-values from tests on answers to open questions (Fisher test in the first column and Barnard test in the rest).
<p>Obtained p-values from tests on answers to open questions (Fisher test in the first column and Barnard test in the rest).</p
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