199480-96-1Relevant academic research and scientific papers
Polyaniline supported cobalt(II)-salen catalyst: One pot synthesis of B-phenylisoserine derivaties from cinnamoyl amide
Das, Bhaskar C.,Iqbal, Javed
, p. 2903 - 2906 (1997)
A novel one pot conversion of cinnamoyl amides to the corresponding phenylisoserine derivatives war developed by employing polyaniline supported cobalt(II)-salen catalysed/formation of the epoxide followed by its opening with anilines at ambient condition
Darzens reaction rate enhancement using aqueous media leading to a high level of kinetically controlled diastereoselective synthesis of steroidal epoxyketones
Li, Bo,Li, Chunbao
, p. 8271 - 8277 (2015/03/18)
Darzens reactions between halocarbonyls and aldehydes have been carried out in water in the presence of a Li+-containing base, a phase-transfer catalyst, and granular polytetrafluoroethylene under mechanical stirring. Reactions using both aromatic and aliphatic aldehydes produced epoxides stereoselectively in good to excellent yields. This is the first time that aliphatic aldehydes with α-H have been used in aqueous Darzens reactions. The Darzens reactions were much faster in water than in organic solvents. This aqueous rate enhancement occurred for Darzens reactions between enantiopure steroidal haloketones and aldehydes, yielding enantiopure spiroepoxides with a high level of kinetically controlled diastereoselectivity. Chromatography was avoided in the purifications of the steroidal spiroepoxides. This is an example of preparing enantiopure epoxyketones via aqueous Darzens reaction using chiral α-haloketone substrates.
Highly efficient alkene epoxidation and aziridination catalyzed by iron(II) salt + 4,4′,4″-trichloro-2,2′:6′,2″-terpyridine/ 4,4″-dichloro-4′-O-PEG-OCH3-2,2′:6′,2″- terpyridine
Liu, Peng,Wong, Ella Lai-Ming,Yuen, Angella Wing-Hoi,Che, Chi-Ming
supporting information; experimental part, p. 3275 - 3278 (2009/05/27)
(Chemical Equation Presented) "Iron(II) salt + 4,4′,4″- trichloro-2,2′:6′,2″-terpyridine" is an effective catalyst for epoxidation and aziridination of alkenes and intramolecular amidation of sulfamate esters. The epoxidation of allylic-substituted cycloalkenes achieved excellent diastereoselectivities up to 90%. ESI-MS results supported the formation of iron-oxo and -imido intermediates. Derivitization of Cl3terpy to O-PEG-OCH3-Cl2terpy renders the terpyridine unit to be recyclable, and the "iron(II) salt + 4,4″-dichloro-4′-O-PEG-OCH3-2,2′:6′,2″- terpyridine" protocol can be reused without a significant loss of catalytic activity in the alkene epoxidation.
Polyaniline supported cobalt(II) catalyst: Oxidation of alkenes with molecular oxygen
Das, Bhaskar C,Iqbal, Javed
, p. 1235 - 1238 (2007/10/03)
Polyaniline supported Co(II) acetate catalyses the oxidation of different alkenes in the presence of 2-methylpropanol under the oxygen atmosphere at ambient temperature. This catalyst can be reused for epoxidations without any decline in its catalytic efficiency.
