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Featuring a beautiful new design, THE EARTH AND ITS PEOPLES, Sixth
Edition, presents world history in a balanced, global framework,
shifting the focus away from political centers of power. This truly
global text for the world history survey course employs fundamental
themes of "environment and technology" and "diversity and
dominance" to explore patterns of humans' interactions with their
surroundings and with each other. The authors' approach reveals how
humanity continues to shape and be shaped by the environment and
how dominant structures and traditions are balanced and challenged
by alternate beliefs. Special emphasis is given to technological
development and how it underlies all human activity. Highly
acclaimed in their fields of study, the authors bring a wide array
of expertise to the program. A combination of strong scholarship
and detailed pedagogy gives the book its reputation for rigor and
student accessibility.
Considering the challenge of sustainability facing our society in
the coming decades, catalysis is without any doubt a research area
of major importance. In this regard, asymmetric organocatalysis,
now considered a pillar of green chemistry, deserves particular
attention. The first chapter of this volume examines the topic of
asymmetric organocatalysis in light of radical chemistry. Recent
important progress in this field has been attained by promoting the
formation and harnessing the high reactivity of open-shell
intermediates. Merging organocatalysis with radical chemistry has
been the key to solving some longstanding bottlenecks, and has also
significantly contributed to reinforcing the key role of
organocatalysis in asymmetric catalysis. This chapter presents the
most significant developments in this area, with a particular focus
on asymmetric SOMO- and photoredox-organocatalyzed transformations.
Chapter 2 focuses on quaternary ammonium salts (R4N+X-), especially
chiral derivatives, and their behavior as unique catalysts in
organocatalysis. Forming chiral ion-pairs capable of promoting
asymmetric reactions, they also operate as unique "transporters"
involved in phase transfer catalytic processes between
liquid-liquid or liquid-solid systems. Furthermore, they offer
unique opportunities when forming cooperative ion-paired entities
R4N+X-, allowing a synergistic implication of the counter-ion X-
either as Bronsted bases or Lewis bases. Specific design of such
chiral catalysts in modern chemistry and better insight into their
mode of activation facilitates efficient and unprecedented chemical
transformations. This chapter provides an overview of the use of
chiral quaternary ammonium salts in organocatalysis, emphasizing
both general mechanistic aspects and the scope of this approach.
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