Abstract
Solvent-induced chirality control in the enantioseparation of 1-phenylethylamine 1 by N-(p-toluenesulfonyl)-(S)-phenylalanine 2 via diastereomeric salt formation was studied. (S)-1·(S)-2 was preferentially crystallized as a less-soluble salt from aqueous alcohol, while (R)-1·(S)-2 salt was mainly obtained by addition of solvents with a six-membered ring such as dioxane, cyclohexane, tetrahydropyran, and cyclohexene to 2-propanol. Further investigations were carried out from the viewpoints of molecular structures, optical rotation measurement, and X-ray crystallographic analyses. Crystallographic analyses have revealed that incorporation of the six-membered ring solvent molecule in (R)-1·(S)-2 without hydrogen bonds changed the molecular conformation of (S)-2 to stabilize the salt, which changed the selectivity of 1 in the enantioseparation.
Copyright © 2010 Wiley-Liss, Inc.
MeSH terms
-
2-Propanol / chemistry
-
Amino Acids / chemistry
-
Crystallography, X-Ray / methods*
-
Cyclohexanes / chemistry
-
Cyclohexenes / chemistry
-
Dioxanes / chemistry
-
Glycine / analogs & derivatives*
-
Glycine / chemistry
-
Hydrogen Bonding
-
Magnetic Resonance Spectroscopy / methods
-
Models, Molecular
-
Molecular Conformation
-
Molecular Structure
-
Optical Rotation
-
Phenethylamines / chemical synthesis
-
Phenethylamines / chemistry*
-
Phenethylamines / isolation & purification*
-
Phenylalanine / analogs & derivatives*
-
Phenylalanine / chemistry
-
Salts / chemistry
-
Solvents / chemistry*
-
Stereoisomerism
-
Water / chemistry
Substances
-
Amino Acids
-
Cyclohexanes
-
Cyclohexenes
-
Dioxanes
-
N-(p-toluenesulfonyl)-(R)-phenylglycine
-
N-(p-toluenesulfonyl)-(S)-phenylalanine
-
N-benzenesulfonyl-(S)-phenylalanine
-
Phenethylamines
-
Salts
-
Solvents
-
Water
-
cyclohexene
-
Phenylalanine
-
Cyclohexane
-
1,4-dioxane
-
2-Propanol
-
Glycine