Chiral recyclable dimeric and polymeric Cr(III) salen complexes catalyzed aminolytic kinetic resolution of trans-aromatic epoxides under microwave irradiation.
Aminolytic kinetic resolution (AKR) of trans-stilbene oxide and trans-beta-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-beta-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 degrees 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.
Kureshy
Rukhsana I
RI
Discipline of Inorganic Materials and Catalysis, Central Salt and Marine Chemicals Research Institute, Bhavnagar 364 002, Gujarat, India. rukhsana93@yahoo.co.in
Prathap
K Jeya
KJ
Singh
Surendra
S
Agrawal
Santosh
S
Khan
Noor-Ul H
NU
Abdi
Sayed H R
SH
Jasra
Raksh V
RV
D002857:Chromium / Q000737:chemistry* / Q000528:radiation effects; D019281:Dimerization; D004852:Epoxy Compounds / Q000737:chemistry; D005029:Ethylenediamines / Q000737:chemistry* / Q000528:radiation effects; D008872:Microwaves; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry* / Q000528:radiation effects*; D011108:Polymers / Q000737:chemistry / Q000528:radiation effects; D013237:Stereoisomerism