Novel Chiral Biaryl Bis(oxazolines)
31 December 2000 (online)
Novel chiral biaryl bis(oxazoline) have been prepared through a complimentary use of three synthetic methods. The method of choice is determined by the structure of the oxazoline. For bis(oxazolines) containing ethylene spacers between the aromatic ring and the oxazoline groups, a general alkylation procedure based on 2-methyl-2-oxazoline has been developed and found to give very good yields (75-87%) of the desired products. Bis(oxazolines) with the oxazoline moiety attached directly to the aromatic ring were prepared by Ullmann coupling of the appropriate bromoaryl oxazolines. Those containing oxymethylene spacers were prepared by the standard method involving condensation of amino alcohols with the appropriate dicarboxylic acids (84).
Four novel chiral biaryl bis(oxazolines) (3-6) have been synthesized