Properties and Reactions of Substituted 1,2-Thiazetidine 1,1-Dioxides: Chiral Mono- and Bicyclic 1,2-Thiazetidine 1,1-Dioxides fromα-Amino Acids
作者:Alexandra Meinzer、Andrea Breckel、Bassam Abu Thaher、Nico Manicone、Hans-Hartwig Otto
DOI:10.1002/hlca.200490021
日期:2004.1
New chiral mono- and bicyclic β-sultams, valuable building blocks for drug synthesis, have been prepared from L-Ala, L-Val, L-Leu, L-Ile, L-Phe, L-Cys, L-Ser, L-Thr, and D-penicillamine by transformation of the COOH group into a methylsulfonyl chloride function, followed by cyclization under basic conditions. Selected properties, derivatives, and reactions of the β-sultams are described.
Novel chiral aminoacidderivedionicliquid crystals with amine and amide moieties as spacers between the imidazolium head group and the alkyl chain were synthesised. The key step in the synthesis utilised the relatively uncommon SO3 leaving group in a microwave‐assisted reaction. The mesomorphic properties of the mesogens were determined by differential scanning calorimetry (DSC), polarising optical
Synthesis of chiral iminoalkyl functionalised N-heterocyclic carbenes and their use in asymmetric catalysis
作者:Mahboub Merzouk、Theo Moore、Neil A. Williams
DOI:10.1016/j.tetlet.2007.10.049
日期:2007.12
A library of new chiral iminoalkyl imidazoliumsalts has been synthesised from amino acids using a modular design approach. Deprotonation with silver oxide yields silver carbene transfer reagents, which can be used as ligand sources in asymmetric catalysis. Preliminary testing has shown that the ligands induce enantioselectivity in the palladium-catalysed allylic alkylation of 1,3-diphenylprop-3-enyl
A novel class of chiral-amine-functionalized ionic liquids (CAFILs) has been synthesized efficiently from natural amino acids, and their structures have been determined by spectroscopic analysis and low temperature X-ray diffraction analysis. The CAFILs have been characterized by physical properties such as melting point, glass transition temperature, thermal degradation and specific rotation. NMR measurements indicate that the CAFILs may be promising alternatives in the field of chiral discrimination. (c) 2006 Elsevier Ltd. All rights reserved.