29681-38-7Relevant articles and documents
Asymmetric synthesis of (S)-(-)-acromelobinic acid
Adamczyk, Maciej,Akireddy, Srinivasa Rao,Reddy, Rajarathnam E.
, p. 2385 - 2387 (2001)
A total synthesis of (S)-(-)-acromelobinic acid 2, which was isolated from clitocybe acromelalga, was achieved via an asymmetric hydrogenation protocol. Dehydroamino acid derivative 12 was prepared from 2,5-lutidine 5 and subjected to asymmetric hydrogenation using (S,S)-[Rh(Et-DuPHOS)(COD)]BF4 to give the (S)-(+)-pyridylalanine derivative 13 in 93% yield and >96% e.e. Removal of the protecting groups in (S)-(+)-13 afforded (S)-(-)-acromelobinic acid 2.
SUBSTITUTED BENZOXAZOLES
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Paragraph 1604-1605, (2016/05/10)
The invention relates to substituted benzoxazoles and to processes for their preparation and to their use for preparing medicaments for the treatment and/or prophylaxis of diseases, in particular of cardiovascular disorders, preferably of thrombotic or thromboembolic disorders.
CO2 Conversion into Esters by Fluoride-Mediated Carboxylation of Organosilanes and Halide Derivatives
Frogneux, Xavier,Von Wolff, Niklas,Thuéry, Pierre,Lefèvre, Guillaume,Cantat, Thibault
, p. 2930 - 2934 (2016/03/25)
A one-step conversion of CO2 into heteroaromatic esters is presented under metal-free conditions. Using fluoride anions as promoters for the C-Si bond activation, pyridyl, furanyl, and thienyl organosilanes are successfully carboxylated with CO2 in the presence of an electrophile. The mechanism of this unprecedented reaction has been elucidated based on experimental and computational results, which show a unique catalytic influence of CO2 in the C-Si bond activation of pyridylsilanes. The methodology is applied to 18 different esters, and it has enabled the incorporation of CO2 into a polyester material for the first time. Metal free! A novel methodology is described to convert CO2 into heteroaromatic esters in the presence of organosilanes and organic halides using fluoride anions as promoters for the C-Si bond activation (see scheme). CO2 exhibits a unique catalytic influence in the C-Si bond cleavage of pyridylsilanes, serving as a traceless activator.