A mild and facile synthesis of enamides has been developed, based on nucleophilic addition of electron-rich aromatic and heteroaromatics to an allenamide unit catalyzed by a gold salt. Yields for the transformation were 29−98%.

The syntheses of Zinquin ester [ethyl [2-methyl-8-(p- tolylsulfonylamino )-6-quinolyloxy]acetate] and the corresponding acid, both of which are zinc(II)-specific fluorophores , are described. 6-Methoxy-2-methyl-8-(p- tolylsulfonylamino ) quinoline (2) can be demethylated , with boron tribromide, to form either the expected phenol or a mixture of the phenol and the corresponding 5-bromo derivative depending upon the reaction conditions. These compounds react with ethyl bromoacetate to give the corresponding esters, as well as the 5-ethoxycarbonyl derivative formed by electrophilic substitution. Halogenation of the sulfonamide (2) occurs readily at the 5-position. The 5-iodo product undergoes a Heck coupling with ethyl acrylate . The crystal structures of ethyl [5-ethoxycarbonylmethyl-2-methyl-8-(p- tolylsulfonylamino )-6-quinolyloxy]acetate and [5-carboxymethyl-2-methyl-8-(p- tolylsulfonylamino )-6-quinolyloxy]acetic acid are described.

An approach to highly functionalized tetrahydrofuran derivatives based upon a novel Oxa-Michael/Michael dimerization of cis-gamma-hydroxyenones is presented. The reaction begins with either 1,2-dioxines or trans-gamma-hydroxyenones and proceeds by addition of one molecule of trans-gamma-hydroxyenone to another molecule of cis- or trans-gamma-hydroxyenone catalyzed by an alkoxide or hydroxide base. Subsequent intramolecular Michael addition of the keto-enolate gives the observed tetrahydrofurans. Substitution at both the 2- and 4-positions of the gamma-hydroxyenone is tolerated; however, for 4-substituted gamma-hydroxyenones, selectivity issues arise due to the possibility of heterochiral or homochiral dimerizations. The major products were those with all contiguous groups trans.

The synthesis and fluorescent properties in the absence and presence of zinc(II) of a range of 2-substituted derivatives of N-(6-methoxy-2-methyl-8-quinolyl)-4-methylbenzenesulfonamide are described. These analogues formed complexes with zinc(II) as indicated by a bathochromic shift in their UV/vis spectra. Analogues with isobutenyl and isobutyl side chains at the 2-position formed fluorescent complexes whose fluorescence was stronger than that of the 2-methyl-containing parent. These derivatives were converted, via conversion to the phenol with boron tribromide and reaction with ethyl bromoacetate, to systems with ester-containing side chains analogous to zinquin ester, a specific cellular fluorophore for zinc(II). All of these ester derivatives formed complexes with zinc(II) resulting in a bathochomic shift in their UV/vis spectra. Compounds with isobutyl, isobutenyl, and styryl side chains exhibited increased fluorescence compared to that of zinquin ester in the presence of zinc(II). The compound with the 2-isobutyl side chain was more selective in its fluorescence for zinc(II) over cadmium(II) compared to zinquin ester.