Analytical optical resolution of bromochlorofluoromethane by enantioselective inclusion into a tailor-made cryptophane and determination of its maximum rotation
01 Nov 1985-Journal of the American Chemical Society (American Chemical Society)-Vol. 107, Iss: 24, pp 6993-6996
TL;DR: A l'aide de la spectrometrie RMN, on etudie le dedoublement optique du bromochlorofluoromethane qui est inclus dans une cavite de compose chiral le cryptophane C.
Abstract: A l'aide de la spectrometrie RMN, on etudie le dedoublement optique du bromochlorofluoromethane qui est inclus dans une cavite de compose chiral le cryptophane C
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TL;DR: Noncovalent synthesis based on the reversible formation of multiple hydrogen bonds is described and the development of novel materials (nanotubes, liquid crystals, polymers, etc.) and principles that recently have emanated from this intriguing field of research are summarized.
Abstract: Hydrogen bonds are like human beings in the sense that they exhibit typical grouplike behavior. As an individual they are feeble, easy to break, and sometimes hard to detect. However, when acting together they become much stronger and lean on each other. This phenomenon, which in scientific terms is called cooperativity, is based on the fact that 1+1 is more than 2. By using this principle, chemists have developed a wide variety of chemically stable structures that are based on the reversible formation of multiple hydrogen bonds. More than 20 years of fundamental studies on these phenomena have gradually developed into a new discipline within the field of organic synthesis, and is nowadays called noncovalent synthesis. This review describes noncovalent synthesis based on the reversible formation of multiple hydrogen bonds. Starting with a thorough description of what the hydrogen bond really is, it guides the reader through a variety of bimolecular and higher order assemblies and exemplifies the general principles that determine their stability. Special focus is given to reversible capsules based on hydrogen-bonding interactions that exhibit interesting encapsulation phenomena. Furthermore, the role of hydrogen-bond formation in self-replicating processes is actively discussed, and finally the review briefly summarizes the development of novel materials (nanotubes, liquid crystals, polymers, etc.) and principles (dynamic libraries) that recently have emanated from this intriguing field of research.
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TL;DR: The unique behavior that emerges from molecules that are simultaneously encapsulated is described and includes new forms of stereochemistry, isomerism, and asymmetry inside capsules.
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450 citations
TL;DR: A number of rigid, hollow organic host compounds have been designed and synthesized with interior cavities large enough to incarcerate organic guest compounds as mentioned in this paper, and some of these hosts are closed-surface spheres whose guest molecules are permanently incarcerated during synthesis.
Abstract: Rigid, hollow organic host compounds have been designed and synthesized with interior cavities large enough to incarcerate organic guest compounds. Some of these hosts are closed-surface spheres whose guest molecules are permanently incarcerated during synthesis. Other hosts contain portals in their shells, shaped to allow the passage only of complementary guest molecules between the inner and bulk phases. The inner phases uniquely constrain guest movements, provide a medium for reactions, and shelter molecules that self-destruct in bulk phases.
360 citations
TL;DR: In this paper, the authors discuss the contributions provided by synthetic cyclophanes as hosts to the understanding of molecular complexation of neutral organic guest molecules in aqueous and organic solvents.
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353 citations
TL;DR: Host-Guest Complexes in the Solid: Raman Microspectrometry 111 and Dynamics of the Guest in the Cryptophane Cavity 7.1.
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348 citations