4075-07-4Relevant articles and documents
Merging Halogen-Atom Transfer (XAT) and Cobalt Catalysis to Override E2-Selectivity in the Elimination of Alkyl Halides: A Mild Route towardcontra-Thermodynamic Olefins
Zhao, Huaibo,McMillan, Alastair J.,Constantin, Timothée,Mykura, Rory C.,Juliá, Fabio,Leonori, Daniele
supporting information, p. 14806 - 14813 (2021/09/18)
We report here a mechanistically distinct tactic to carry E2-type eliminations on alkyl halides. This strategy exploits the interplay of α-aminoalkyl radical-mediated halogen-atom transfer (XAT) with desaturative cobalt catalysis. The methodology is high-yielding, tolerates many functionalities, and was used to access industrially relevant materials. In contrast to thermal E2 eliminations where unsymmetrical substrates give regioisomeric mixtures, this approach enables, by fine-tuning of the electronic and steric properties of the cobalt catalyst, to obtain high olefin positional selectivity. This unprecedented mechanistic feature has allowed access tocontra-thermodynamic olefins, elusive by E2 eliminations.
An efficient approach to azolyl-substituted steroids through copper-catalyzed Ullmann C-N coupling
Kotovshchikov, Yury N.,Latyshev, Gennadij V.,Lukashev, Nikolay V.,Beletskaya, Irina P.
, p. 7823 - 7832 (2013/12/04)
Ullmann-type C-N coupling of vinyliodides and nitrogen heterocycles has been shown to be a straightforward and highly efficient approach to azolyl-substituted steroids. The amination reaction proved sensitive to steric effects exerted by the substituents in both iodide and heterocycle. The influence of reaction conditions (catalyst, base, solvent, and temperature) on conversion of the iodosteroid and the selectivity was investigated. The catalytic system comprising 10 mol-% CuI and 20 mol-% dipivaloylmethane with K2CO3 in dimethyl sulfoxide at 100 °C delivered the best result. The elaborated protocol has permitted iodosteroids with various substituted indoles, imidazoles, carbazole, indazole, and sec-amides to be coupled, affording the corresponding azolyl-substituted steroids in good to excellent yields. A facile synthetic route to azolyl-substituted steroids has been developed on the basis of Cu-catalyzed cross-coupling of steroidal vinyliodides and aromatic NH-heterocycles. The protocol has been shown to be convenient and highly efficient, affording coupling products in good to excellent yields. Copyright
Androstane steroids as neurochemical initiators of change in human hypothalamic function and related pharmaceutical compositions and methods
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, (2008/06/13)
The invention relates to a method of altering hypothalamic function in an individual. The method comprises nasally administering a human semiochemical, e.g. an Androstane steroid, or a pharmaceutical composition containing a semiochemical, such that the ligand semiochemical binds to a specific neuroepithelial receptor. The steroid or steroids is/are preferably administered in the form of a pharmaceutical composition containing one or more pharmaceutically acceptable carriers. Other embodiments of the invention include pharmaceutical compositions containing the steroids.
