350047-60-8Relevant academic research and scientific papers
Chiral recyclable dimeric and polymeric Cr(III) salen complexes catalyzed aminolytic kinetic resolution of trans-aromatic epoxides under microwave irradiation
Kureshy, Rukhsana I.,Prathap, K. Jeya,Singh, Surendra,Agrawal, Santosh,Khan, Noor-Ul H.,Abdi, Sayed H.R.,Jasra, Raksh V.
, p. 809 - 815 (2013/08/22)
Aminolytic kinetic resolution (AKR) of trans-stilbene oxide and trans-β-methyl styrene oxide proceeded smoothly under microwave irradiation using chiral dimeric and polymeric Cr(III) salen complexes as efficient catalysts, giving regio-, diastereo-, and enantioselective anti-β-amino alcohols in high yields (49%) and chiral purity (ee up to 94%) in case of 4-methylaniline within 2 min. The kinetic resolution system is approximately five times faster than traditional oil bath heating at 70°C and 420 times faster than the reaction conducted at room temperature with concomitant recovery of respective chirally enriched epoxides (ee, 92%) in excellent yields (up to 48%). The catalyst 1 worked well in terms of enantioselectivity than the catalyst 2, but both the catalysts were easily recovered and reused five times with the retention of its efficiency.
Enantioselective epoxidation of non-functionalised alkenes using a urea-hydrogen peroxide oxidant and a dimeric homochiral Mn(III)-Schiff base complex catalyst
Kureshy, Rukhsana I,Khan, Noor-ul H.,Abdi, Sayed H.R,Patel, Sunil.T.,Jasra, Raksh V.
, p. 433 - 437 (2007/10/03)
The catalytic enantioselective epoxidation of chromenes, indene and styrene using a urea-hydrogen peroxide adduct as an oxidising agent and the novel dimeric homochiral Mn(III)-Schiff base catalyst 1 has been investigated in the presence of carboxylate salts and nitrogen and oxygen coordinating co-catalysts. Conversions of more than 99% were obtained with all alkenes except styrene. Absolute chiral induction, as determined by 1H NMR using the chiral shift reagent (+)-Eu(hfc)3, was obtained in the case of nitro- and cyanochromene. The catalyst could be re-used for up to five cycles with some loss of activity due to degradation of the catalyst under epoxidation condition with retention of e.e.'s.
