Diastereoselective preparation of (R)- and (S)-2-methoxy-2-phenylpent-3-ynoic acids and their use as reliable chiral derivatizing agents.
Benzoyl-S,O-acetals 1a and 1b were used as chiral auxiliaries to achieve the diastereoselective preparation of both enantiomers of 2-methoxy-2-phenylpent-3-ynoic acids (MPPAs). The latter were condensed with several chiral secondary alcohols and some primary amines to evaluate their potential as chiral derivatizing agents (CDAs). The (1)H NMR spectra of the corresponding esters and amides showed strong consistency with the absolute configuration of the carbinol and amine moieties, whose observed ΔδL(1) and ΔδL(2) values were in the ranges of 0.1-0.4 and 0.02-0.12 ppm, respectively.
Departamento de Química Orgánica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Prol. de Carpio y Plan de Ayala, México, D.F., 11340 Mexico.
Salvador
S
Pérez-Estrada
Pedro
P
Joseph-Nathan
Hugo A
HA
Jiménez-Vázquez
Manuel E
ME
Medina-López
Francisco
F
Ayala-Mata
L Gerardo
LG
Zepeda
D000080:Acetals / Q000737:chemistry*; D000438:Alcohols / Q000737:chemistry*; D000577:Amides / Q000737:chemistry; D000588:Amines / Q000737:chemistry*; D004952:Esters / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D000432:Methanol / Q000737:chemistry; D008958:Models, Molecular; D015394:Molecular Structure; D010421:Pentanoic Acids / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism; D013816:Thermodynamics
D000080:Acetals; D000438:Alcohols; D000577:Amides; D000588:Amines; D004952:Esters; D010421:Pentanoic Acids; D000432:Methanol