title: Formation and characterization of a multicomponent equilibrium system derived from cis- and trans-1-aminomethylcyclohexane-1,2-diol.
abstract: Both cis and trans isomers of amino diols 3-6 were prepared stereoselectively. In the reactions between 3-6 and phenyl isothiocyanate, the ring closure proceeded regioselectively and resulted only in spiro derivatives of 2-phenyliminooxazolidines 9, 10, 13, and 14. The reaction of cis- (or trans-)1-aminomethylcyclohexane-1,2-diol 4 (or 6) with 1 equiv of an aromatic aldehyde 15a-g in EtOH at room temperature resulted in a complex, multicomponent equilibrium mixture of 16a-g and 18a-g (or 17a-g and 19a-g), in each case consisting of a five-component, ring-chain tautomeric system 16A-E (or 17A-E), involving the Schiff base, two epimeric spirooxazolidines, two epimeric condensed 1,3-oxazines, and some of the four tricyclic compounds 18A-D (or 19A-D). The five-component, ring-chain equilibria were found to be adequately described by the Hammett-Brown linear free energy equation.
authors.affiliation: Institute of Pharmaceutical Chemistry, University of Szeged, Hungary.
authors.forename: Anasztázia
authors.initials: A
authors.lastname: Hetényi
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Szakonyi
authors.forename: Karel D
authors.initials: KD
authors.lastname: Klika
authors.forename: Kalevi
authors.initials: K
authors.lastname: Pihlaja
authors.forename: Ferenc
authors.initials: F
authors.lastname: Fülöp