14135-36-5Relevant academic research and scientific papers
An efficient metal-free pathway to vinyl thioesters with calcium carbide as the acetylene source
Rodygin, Konstantin S.,Ananikov, Valentine P.
supporting information, p. 482 - 486 (2016/01/30)
Chemical reactions involving high-pressure acetylene are not easily performed in a standard laboratory setup. The risk of explosion and technical difficulties drastically complicate the equipment and greatly increase the cost. In this study, we propose th
Vinyl sulfoxides as stereochemical controllers in intermolecular Pauson-Khand reactions: Applications to the enantioselective synthesis of natural cyclopentanoids
Rodriguez Rivero, Marta,Alonso, Ines,Carretero, Juan C.
, p. 5443 - 5459 (2007/10/03)
The use of sulfoxides as chiral auxiliaries in asymmetric intermolecular Pauson-Khand reactions is described. After screening a wide variety of substituents on the sulfur atom in α,β-unsaturated sulfoxides, the readily available o-(N,N-dimethylamino)phenyl vinyl sulfoxide (1i) has proved to be highly reactive with substituted terminal alkynes under N-oxide-promoted conditions (CH3CN, 0°C). In addition, these Pauson-Khand reactions occurred with complete regioselectivity and very high diastereoselectivity (de = 86→96%, (S,RS) diastereomer). Experimental studies suggest that the high reactivity exhibited by the vinyl sulfoxide 1i relies on the ability of the amine group to act as a soft ligand on the alkyne dicobalt complex prior to the generation of the cobaltacycle intermediate. On the other hand, both theoretical and experimental studies show that the high stereoselectivity of the process is due to the easy thermodynamic epimerization at the C5 center in the resulting 5-sulfinyl-2- cyclopentenone adducts. When it is taken into account that the known asymmetric intermolecular Pauson-Khand reactions are limited to the use of highly reactive bicyclic alkenes, mainly norbornene and norbornadiene, this novel procedure constitutes the first asymmetric version with unstrained acyclic alkenes. As a demonstration of the synthetic interest of this sulfoxide-based methodology in the enantioselective preparation of stereochemically complex cyclopentanoids, we have developed very short and efficient syntheses of the antibiotic (-)-pentenomycin I and the (-)-aminocyclopentitol moiety of a hopane triterpenoid.
REACTIONS OF BENZOTHIAZOL-2-THIONE AND BENZOTHIAZOL-2-ONE WITH ACETYLENE
Abramova, N. D.,Afonin, A. V.,Naumova, G. G.
, p. 223 - 224 (2007/10/02)
Reaction of benzothiazol-2-thione and benzothiazol-2-one with acetylene in the presence of potassium hydroxide or cadmium acetate gives 2-vinylthiobenzothiazole and 3-vinylbenzothiazol-2-one, respectively.Benzothiazol-2-thione is partially converted to benzothiazol-2-one by the action of Cd(OAc)2.Under vinylation conditions the latter also forms 2-vinylthioaniline.
GAS/SOLID-REACTIONS WITH SULFUR COMPOUNDS
Kaupp, Gerd,Luebben, Doris,Sauerland, Olaf
, p. 109 - 120 (2007/10/02)
The various types of gas/solid-reactions (addition, elimination, substitution, condensation, catalyzed cycloaddition) in different branches of sulfur chemistry (heterocycles, S-vinyl-compounds, thioethers, thiols, sulfur dioxide) are reviewed, new types a
