Search results for "Imidoyl chloride"
showing 3 items of 3 documents
Synthesis of a New Fluorinated Oxazolidinone and Its Reactivity as a Chiral Auxiliary in Aldol Reactions.
2007
A new enantiomerically pure fluorinated oxazolidinone has been prepared from a fluorinated imidoyl chloride and an optically pure sulfoxide. The diastereoselective reduction of the β-iminosulfoxide thus formed followed by elimination of the sulfoxide and cyclization of the created aminoalcohol furnishes the desired product. The fluorinated oxazolidinone was subsequently used as a chiral auxiliary in Aldol reactions. We also found that the selective formation of the syn-Evans and syn-non-Evans diastereoisomer can be controlled by adjusting the Lewis acid/base ratio.
Rod-Length Dependent Aggregation in a Series of Oligo(p-benzamide)-Block-Poly(ethylene glycol) Rod-Coil Copolymers
2005
The synthesis of a series of rod-coil diblock copolymers with flexible poly(ethylene oxide) chains (M n = 5 000 g mol -1 ) and rod blocks consisting of monodisperse oligo(p-benzamide)s is described. The formation of defined supramolecular aggregates in solution as well as the solid state has been analyzed. The length of the oligo(p-benzamide)s has been systematically varied from n = 1 to 7 units. The influence of n on aggregation in chloroform and aqueous solution was investigated by GPC as well as UV-vis spectroscopy. A critical aggregation length was found for chloroform (n = 5) and water (n = 4), below which no aggregation is observed under otherwise identical experimental conditions. Ag…
An Efficient and Simple Entry to N-Substituted beta-Enamino Acid Derivatives from 2-Alkyl-2-oxazolines and 2-Alkyl-2-thiazolines.
1996
Reaction of azaenolates of 2-alkyl-oxa(thia)zolines 6 with imidoyl chlorides 7 as electrophiles to furnish masked N-substituted beta-enamino acid derivatives 1-2 in 70-90% yield is described. Alternative routes are discussed. Compounds 1-2 generally appear in one tautomeric form, imino or enamino, depending on the nature of the imidoyl chloride. The configuration of the enamino moiety (Z) and the conformation (s-cis) of compounds 1-2 obtained were established by an NMR study and unequivocally set by nuclear Overhauser effect difference experiments. An X-ray structure of compound 1e is also reported, showing a strong intramolecular NH.N hydrogen bond. Ab initio calculations (HF/3-21G and HF/…