do Carmo, Lucas F.; Silva, Simone C.; Machado, Matheus V.; Prata, Paloma S.; Junior, Alberto Wisniewski; Vidal, Diogo M.; Villar, Jose Augusto F. P. published the artcile< The role of L-proline and co-catalysts in the enantioselectivity of OXA-Michael-Henry reactions>, Application In Synthesis of 5153-70-8, the main research area is nitrophenyl chromene preparation enantioselective; salicylaldehyde nitrostyrene Michael Henry tandem proline catalyst.
In this work, a study of the OXA-Michael-Henry reactions between salicylaldehyde and β-nitrostyrenes 2-R1-3-R2-4-R3C6H2CH=CHNO2 (R1 = R2 = H, R3 = Cl; R1 = R2 = H, R3 = Br; R1 = R2 = 2,3-Cl2, R3 = H, etc.), catalyzed by proline derivatives e.g., L-proline was described. The corresponding (R)-3-nitro-2-phenyl-2H-chromenes I were obtained in 55% enantiomeric excess (ee, 20 mol% L-proline) and 70% ee (stoichiometric amount) employing Ti(OiPr)4 as Lewis acid. Despite the ee obtained, this result represents the highest enantioselectivity obtained in this reaction. Therefore, this work demonstrated that it is possible to obtain considerable enantiomeric excesses in OXA-Michael-Henry reactions using L-proline, an inexpensive and accessible amino acid.
Journal of the Brazilian Chemical Society published new progress about Benzopyrans Role: SPN (Synthetic Preparation), PREP (Preparation). 5153-70-8 belongs to class chlorides-buliding-blocks, and the molecular formula is C8H6ClNO2, Application In Synthesis of 5153-70-8.
Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics