13949-65-0Relevant academic research and scientific papers
Access to Optically Enriched α-Aryloxycarboxylic Esters via Carbene-Catalyzed Dynamic Kinetic Resolution and Transesterification
Liu, Bin,Song, Runjiang,Xu, Jun,Majhi, Pankaj Kumar,Yang, Xing,Yang, Song,Jin, Zhichao,Chi, Yonggui Robin
supporting information, p. 3335 - 3338 (2020/04/30)
Optically active α-aryloxycarboxylic acids and their derivatives are important functional molecules. Disclosed here is a carbene-catalyzed dynamic kinetic resolution and transesterification reaction for access to this class of molecules with up to 99% yields and 99:1 er values. Addition of a chiral carbene catalyst to the ester substrate leads to two diastereomeric azolium ester intermediates that can quickly epimerize to each other and thus allows for effective dynamic kinetic resolution to be realized. The optically enriched ester products from our reaction can be quickly transformed to chiral herbicides and other bioactive molecules.
Pentanoic acid derivatives
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, (2008/06/13)
Formula (I) compounds: wherein R1 is alkyl substituted by fluorine(s); R2 is hydroxy, alkoxy, alkoxy substituted by phenyl, NR3R4, in which R3, R4 is (i) hydrogen, (ii) alkyl, (iii) phenyl, (iv) phenyl substituted by alkoxy or carboxyl, (v) heterocyclic ring containing nitrogen atom, (vi) alkyl substituted by phenyl, phenyl subsituted by alkoxy or carboxyl, heterocyclic ring containing nitrogen atom, (vii) the nitrogen bonded to R3 and R4, taken together is a saturated heterocyclic ring or amino acid residue; and non-toxic salts and acid addition salts thereof. Also, Formula (X) compounds: wherein n is 0 or 1, R11 is hydrogen and chlorine, R5 is R7—CH2— or R8, or R5 and R11, taken together is alkylidene; R6 is hydroxy, alkoxy, alkoxy substituted by phenyl, NR9R10, in which R9, R10 is (i) hydrogen, (ii) alkyl, (iii) phenyl, (iv) phenyl substituted by alkoxy or carboxyl, (v) heterocyclic ring containing nitrogen atom, (vi) alkyl substituted by phenyl, phenyl-substituted by alkoxy or carboxyl, heterocyclic ring containing nitrogen atom, (vii) the nitrogen bonded to R9 and R10, taken together is a saturated heterocyclic ring or amino acid residue, R7 is (i) F—(CH2)m— or F3C—CH2—, (ii) alkyl subsstituted by chlorine, (iii) alkyl substituted by alkoxy, cycloalkyl, phenyl, phenoxy; R8 is alkyl, alkenyl, alkoxy, alkylthio, cycloalkyl, phenyl, phenoxy. Non-toxic and acid addition salts thereof are useful to prevent and/or treat neurodegenerative disease (e.g., Alzheimer's) and neuronal dysfunction by stroke or traumatic injury (e.g., Multiple sclerosis).
