Results 231 to 240 of about 82,507 (282)
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Dynamics of Carbene Cycloadditions
Journal of the American Chemical Society, 2011Quasiclassical trajectory calculations using quantum mechanical energies and forces generated by the Venus and Gaussian programs provide for the first time a detailed dynamical picture of singlet carbene, CCl(2) and CF(2), cycloadditions to alkenes on the B3LYP/6-31G* surface.
Lai, Xu, Charles E, Doubleday, K N, Houk
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Cycloadditions with Metauo-Phosphaalkenes
Phosphorus, Sulfur, and Silicon and the Related Elements, 1994Abstract Cycloadditions of metallo-phosphaalkenes such as (C5Me5)(C0)2Fe− P=CR1R2 (R1 = R2 = SiMe3, NMe2; R1 = Ph, R2 = SiMe3) are performed with isocyanides, electron-poor alkenes, alkynes and heteroal ...
Weber, Lothar +2 more
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Retro‐Cycloaddition Reaction of Pyrrolidinofullerenes.
ChemInform, 2005AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Nazario, Martín +5 more
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From Organocatalytic Cycloadditions to Asymmetric Higher-Order Cycloadditions
2023Controlling periselectivity and stereoselectivity of cycloadditions for systems having >6p-electrons has been a challenge ever since the introduction of the Woodward-Hoffmann rules. This chapter outlines how organocatalysis has been a key factor to control cycloadditions for reactions having >6p-electrons - termed higher-order cycloadditions. The
Jørgensen, Karl Anker, Houk, K.N.
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1994
Die thermische [2+2]Cycloaddition von Alkenen 1 ist nach den Woodward-Hoffmann-Regeln 1) suprafacial symmetrieverboten und kann nur in speziellen Fallen erfolgreich durchgefuhrt werden. Hingegen ist das photochemische Pendant erlaubt und wird als praparativ wertvolle Methode zur Bildung von Vierringsystemen 2 vielfaltig genutzt.2–4)
Thomas Laue, Andreas Plagens
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Die thermische [2+2]Cycloaddition von Alkenen 1 ist nach den Woodward-Hoffmann-Regeln 1) suprafacial symmetrieverboten und kann nur in speziellen Fallen erfolgreich durchgefuhrt werden. Hingegen ist das photochemische Pendant erlaubt und wird als praparativ wertvolle Methode zur Bildung von Vierringsystemen 2 vielfaltig genutzt.2–4)
Thomas Laue, Andreas Plagens
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Staudinger ketene cycloaddition
2009Also known as the Staudinger reaction. [2 + 2]-Cycloaddition of ketene and imine to form β-lactams. Other coupling partners for ketenes include: olefin to give cyclobutanone and carbonyl to give β-lactone.
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Cycloadditions and Cycloreversions I. [2+2]-Cycloaddition
1992It was pointed out in the preceding chapter that correlation diagrams can be read from right to left as easily as from left to right. This is certainly true from the formal viewpoint of orbital symmetry, but does not preclude the need to examine the geometric and energetic consequences of the nuclear motions involved.
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2010
This chapter deals with enantioselective organocatalytic cycloaddition reactions. Several cinchona alkaloids have been recently demonstrated as efficient chiral organocatalysts for enantioselective Diels−Alder reactions. Thus, excellent results were obtained for the Diels−Alder reaction of 3-vinylindoles with maleimides catalysed by a ...
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This chapter deals with enantioselective organocatalytic cycloaddition reactions. Several cinchona alkaloids have been recently demonstrated as efficient chiral organocatalysts for enantioselective Diels−Alder reactions. Thus, excellent results were obtained for the Diels−Alder reaction of 3-vinylindoles with maleimides catalysed by a ...
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