253336-68-4Relevant articles and documents
Utility of Nitrogen Extrusion of Azido Complexes for the Synthesis of Nitriles, Benzoxazoles, and Benzisoxazoles
Nimnual, Phongprapan,Tummatorn, Jumreang,Thongsornkleeb, Charnsak,Ruchirawat, Somsak
, p. 8657 - 8667 (2015/09/15)
The utility of the nitrogen extrusion reaction of azido complexes, generated in situ from the corresponding aldehydes or ketones with TMSN3 in the presence of ZrCl4 or TfOH, has been described. These azido complexes could undergo three different pathways, depending on the substrates. First, azido methanolate complexes or imine diazonium ions could lead to benzisoxazole products via an intramolecular nucleophilic substitution. Second, imine diazonium ions could also undergo either the elimination of proton to provide nitrile products in good to excellent yields or an aryl migration, followed by an intramolecular nucleophilic addition, to give benzoxazole products in good yields.
Total synthesis of 14C-labeled procyanidin B2
Viton, Florian,Landreau, Cyrille,Rustidge, David,Little, Gill,Robert, Fabien,Williamson, Gary,Barron, Denis
scheme or table, p. 371 - 374 (2011/05/05)
During the last decades, many in vitro and in vivo studies have shown the beneficial effects on health of procyanidins. However, their absorption and metabolism is still not fully understood and some aspects are still controversial. In order to have a clearer picture of the metabolism of procyanidins, the use of labelled compounds is essential. In this context, the enantioselective synthesis of 14C-radiolabelled procyanidin B2 was developed in our laboratories. It was achieved in fourteen 'hot' steps, involving as key steps the Sharpless dihydroxylation of an elaborated alkene, a stereoselective intramolecular cyclization to benzylated (+)-catechin and the condensation of two (-)-epicatechin units. 11 mCi of protected procyanidin B2 were obtained from 524 mCi of potassium [14C]cyanide. Copyright
A simple and highly efficient one-pot chemoselective synthesis of nitriles from aldehydes: Mechanistic insight and selectivity control through modulation of electronic and steric factors
Chakraborti,Kaur,Roy
, p. 1000 - 1006 (2007/10/03)
Aldehydes are converted into nitriles in a one-pot reaction by treatment with H2NOH·HCl in dipolar aprotic solvents under heating. Amongst various solvents NMP offers the best results. No competitive ether cleavage (e.g. methoxy, benzyloxy) or aromatic nucleophilic substitution (e.g. nitro or chloro) takes place for substrates beating such functionalities. Electronic and steric factors around the aldehyde carbon affect the rate of nitrile formation. Excellent to moderate selectivity is observed during intermolecular competition between pair of aldehydes with varying electronic and steric requirements.