Conversion of γ- and δ-Keto Esters into Optically Active Lactams. Transaminases in Cascade Processes was written by Mourelle-Insua, Angela;Zampieri, Luiz Arthur;Lavandera, Ivan;Gotor-Fernandez, Vicente. And the article was included in Advanced Synthesis & Catalysis in 2018.Formula: C12H13FO3 The following contents are mentioned in the article:
A one-pot two-step enzymic strategy has been designed for the production of optically active γ- and δ-lactams in aqueous medium under mild conditions. The approach is based on the biotransamination of Et or Me keto esters bearing different alkyl or aryl substitution patterns at α-position to the ketone functionality. In this manner, the keto esters were transformed into the corresponding amino esters with excellent conversions, which underwent spontaneous cyclisation in the reaction medium without addition of external reagents. Depending on the transaminase selectivity, both lactam enantiomers can be obtained, so initial enzyme screenings were performed using com. available and made in house enzymes. Reaction conditions were optimized focusing on the substrate concentration, temperature and ratio of amine donor vs acceptor. Thus, ten γ- and δ-lactams were obtained in good to high isolated yields (70-90%) and excellent selectivities (94-99%) after one or two days at 30 or 45 °C. This study involved multiple reactions and reactants, such as Methyl 5-(4-fluorophenyl)-5-oxopentanoate (cas: 149437-67-2Formula: C12H13FO3).
Methyl 5-(4-fluorophenyl)-5-oxopentanoate (cas: 149437-67-2) belongs to esters. Esters are also usually derived from carboxylic acids. It may also be obtained by reaction of acid anhydride or acid halides with alcohols or by the reaction of salts of carboxylic acids with alkyl halides. Esters contain a carbonyl center, which gives rise to 120° C–C–O and O–C–O angles. Unlike amides, esters are structurally flexible functional groups because rotation about the C–O–C bonds has a low barrier. Their flexibility and low polarity is manifested in their physical properties; they tend to be less rigid (lower melting point) and more volatile (lower boiling point) than the corresponding amides. Formula: C12H13FO3
Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics