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In 1972, a very powerful catalytic cycle for carbon-carbon bond
formation was 2 first discovered by the coupling reaction of
Grignard reagents at the sp -carbon. Over the past 30 years, the
protocol has been substantially improved and expanded to other
coupling reactions of Li, B, N, O, Al, Si, P, S, Cu, Mn, Zn, In,
Sn, and Hg compounds. These reactions provided an indispensable and
simple methodology for preparative organic chemists. Due to the
simplicity and rel- bility in the carbon-carbon, carbon-heteroatom,
and carbon-metalloid bo- formations, as well as high efficiency of
the catalytic process, the reactions have been widely employed by
organic chemists in various fields. Application of the protocol
ranges from various syntheses of complex natural products to the
preparation of biologically relevant molecules including drugs, and
of sup- molecules, and to functional materials. The reactions on
solid surfaces allow robot synthesis and combinatorial synthesis.
Now, many organic chemists do not hesitate to use transition metal
complexes for the transformation of org- ic molecules. Indeed,
innumerable organic syntheses have been realized by the catalyzed
reactions of transition metal complexes that are not achievable by
t- ditional synthetic methods. Among these, the metal-catalyzed
cross-coupling reactions have undoubtedly contributed greatly to
the development of such a new area of "metal-catalyzed organic
syntheses." An excellent monograph for the cross-coupling reactions
and other met- catalyzed C-C bond-forming reactions recently
appeared in Metal-catalyzed Cross-coupling Reactions (Wiley-VCH,19
Directed metalation is recognized as one of the most useful
methodologies for the regio- and stereoselective generation of
organometallic species, the generation of which necessarily leads
to the selective formation of organic products. Cyclometalation
using Li, Mn, and Pd, and directed hydrometalation and
carbometalation using Al and Zn, have been utilized for regio-
and/or stereoselective synthesis for decades. Recently, a new
chelation-assisted methodology has been developed not only for
controlling regio- and stereoselectivity of reactions, but also for
accelerating reactions. In particular, chelation-methodology has
been utilized as a new activation method, in which a carbon-metal
bond is generated directly from a C-H bond; a reaction rarely
achieved using conventional methods. A wide variety of catalytic
functionalization reactions of C-H bonds by the utilization of a
chelation, have been developed recently and are comprehensively
discussed in this book by leading experts. In addition, new
approaches to directed hydrometalation and directed carbometalation
as a key step are also discussed. A unique stereo- and
regioselective hydroformylation has been developed through the
utilization of directed hydrometalation. The regioselective
Mizoroki-Heck reaction is another example in which directed
carbometalation can be used to achieve a high regioselectivity.
These examples emphasize how these innovative methodologies are
contributing to different fields of chemistry.
What did it mean to be happy in early modern Europe? Positive
emotions in early modern literature and culture includes essays
that reframe historical understandings of emotional life in the
Renaissance, focusing on under-studied feelings such as mirth,
solidarity, and tranquillity. Methodologically diverse and
interdisciplinary, these essays draw from the history of emotions,
affect theory and the contemporary social and cognitive sciences to
reveal rich and sustained cultural attention in the early modern
period to these positive feelings. The book also highlights
culturally distinct negotiations of the problematic binary between
what constitutes positive and negative emotions. A comprehensive
introduction and afterword open multiple paths for research into
the histories of good feeling and their significances for
understanding present constructions of happiness and wellbeing. --
.
In 1972, a very powerful catalytic cycle for carbon-carbon bond
formation was 2 first discovered by the coupling reaction of
Grignard reagents at the sp -carbon. Over the past 30 years, the
protocol has been substantially improved and expanded to other
coupling reactions of Li, B, N, O, Al, Si, P, S, Cu, Mn, Zn, In,
Sn, and Hg compounds. These reactions provided an indispensable and
simple methodology for preparative organic chemists. Due to the
simplicity and rel- bility in the carbon-carbon, carbon-heteroatom,
and carbon-metalloid bo- formations, as well as high efficiency of
the catalytic process, the reactions have been widely employed by
organic chemists in various fields. Application of the protocol
ranges from various syntheses of complex natural products to the
preparation of biologically relevant molecules including drugs, and
of sup- molecules, and to functional materials. The reactions on
solid surfaces allow robot synthesis and combinatorial synthesis.
Now, many organic chemists do not hesitate to use transition metal
complexes for the transformation of org- ic molecules. Indeed,
innumerable organic syntheses have been realized by the catalyzed
reactions of transition metal complexes that are not achievable by
t- ditional synthetic methods. Among these, the metal-catalyzed
cross-coupling reactions have undoubtedly contributed greatly to
the development of such a new area of "metal-catalyzed organic
syntheses." An excellent monograph for the cross-coupling reactions
and other met- catalyzed C-C bond-forming reactions recently
appeared in Metal-catalyzed Cross-coupling Reactions (Wiley-VCH,19
Directed metalation is recognized as one of the most useful
methodologies for the regio- and stereoselective generation of
organometallic species, the generation of which necessarily leads
to the selective formation of organic products. Cyclometalation
using Li, Mn, and Pd, and directed hydrometalation and
carbometalation using Al and Zn, have been utilized for regio-
and/or stereoselective synthesis for decades. Recently, a new
chelation-assisted methodology has been developed not only for
controlling regio- and stereoselectivity of reactions, but also for
accelerating reactions. In particular, chelation-methodology has
been utilized as a new activation method, in which a carbon-metal
bond is generated directly from a C-H bond; a reaction rarely
achieved using conventional methods. A wide variety of catalytic
functionalization reactions of C-H bonds by the utilization of a
chelation, have been developed recently and are comprehensively
discussed in this book by leading experts. In addition, new
approaches to directed hydrometalation and directed carbometalation
as a key step are also discussed. A unique stereo- and
regioselective hydroformylation has been developed through the
utilization of directed hydrometalation. The regioselective
Mizoroki-Heck reaction is another example in which directed
carbometalation can be used to achieve a high regioselectivity.
These examples emphasize how these innovative methodologies are
contributing to different fields of chemistry.
Proceedings of the NSF Research Workshop on Contact
Transformations, Held in Nashville, Tennessee, 1974
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