cis-trans Isomerism of Exocyclic α,β-Unsaturated Indanones and Tetralones

Abstract

oxide mixture (64.4% trans, 27.8% cis, and 7.8% 4,5dihydrooxepine) heated on a steam bath overnight resulted in the disappearance of cis-1,2-divinylethylene oxide. The composition after the heating period was 61.8% trans oxide and 38.2% 4,5-dihydrooxepine.The thermal requirements for ring expansion of 1,2divinylethylene oxide and 1,2-divinylcyclopropane3 are apparently analogous. In both cases, ring expansion of the cis isomer requires about 200°less than the corresponding trans isomer. Extension of valence tautomerism to other small ring heterocycles is currently under investigation in our laboratories. Experimental 3-Chloro-4-acetoxy-1,5-hexadiene.-The procedure used for the preparation of 3-chloro-4-acetoxy-l,5-hexadiene was an adaptation of Searles8 technique for preparation of chloro esters from 1,3-diols.Acetyl chloride, 190 g. (2.44 moles), was added to a stirred suspension of 41.6 g. (0.38 mole) of calcium chloride and 228 g.(2.0 moles) of 1,5-hexadiene-3,4-diol over a period of 45 min. During the addition, the temperature was maintained below 10°. The reaction mixture then was stirred for 40 hr. at room temperature and then 1 hr. at 50°. The dark brown viscous product was poured into ice, neutralized with cold aqueous sodium bicarbonate extracted with ether, and dried over anhydrous potassium carbonate. After filtration and removal of ether, thereChemistry Office, and was monitored by Army Ordnance under Contract No. DA-30-069-ORD-2487.cis-trans Isomerism of Exocyclic

A regioselective 1,3-dipolar cycloaddition of 2-arylidene-1-tetralones with DPNI

“…chemical shift value of olefinic protons at about d ‫ס‬ 7.85, in accordance with 1 H NMR literature data [12]. Reactions of 2-arylidene-1-tetralone with DPNI (generated in situ from N-phenylbenzhydrazidoyl chloride in chloroform solution in the presence of triethylamine at room temperature) led to the formation of 1:1 adducts as a single product in each case, as evidenced by TLC and mass spectral studies.…”

The in vitro Antimycotic Activity and Acute Toxicity of Third-Generation Bezylidenetetralones and Heteroarylidenetetralones

“…The pure compounds were characterised by NMR and infrared spectroscopic methods and elemental analysis. In particular, the appearance of the H-· proton signal in the range of ‰ 8.50-7.60 ppm in the 1 H-NMR spectra unequivocally corroborated their E configuration [12,13]. 10:191-196 For in vitro antimycotic activity, the compounds were dissolved in DMSO (analar), and the activity was tested by a microtitre well technique in triplicate sets, in a liquid casitone medium.…”

“…Nineteen members of this third generation of E-2-benzylidene-1-tetralones (table 1) were synthesised under the new strong acid and base reaction conditions as we intended to introduce heteroaromatic compounds (13)(14)(15)(16)(17)(18)(19), polychlorinated (9-11), ionisable hydroxyl sulphonic and acidic groups [2,4,7] as well as new ether, ester (1, 3, 5, 6) and cyano (12) residues as substituents for comparison to the first and second generation 1-4 and 14 E-2-benzylidene-1-tetralones, respectively. The broad spectrum of antimycotic activity exhibited by 10 of the new compounds (table 3) was generally dependent on the presence of free or ionisable acidic-oxygenated functional groups (2, 4, 7) or nitrogenous residues having free or nonmethylated nitrogen atoms, and specifically when the nitrogen substituent was a 6-membered ring (pyridyl derivatives; 14, 16, 17) and, to a lesser extent, when the nitrogen residue was that of a 5-membered pyrrole ring (19).…”

“…Although the simple E-2-benzylidine-1-tetralones (1-12) were overall less toxic than those where the phenyl group was replaced with a heterocyclic moiety (13)(14)(15)(16)(17)(18)(19), as reflected by their LD 50 values in mice, many were comparably or slightly more toxic than the least toxic commercial agent, amphotericin B. When compared to the most active of the commercial agents, sertaconazole, the in vivo toxicity of the new compounds was found to be marginally better.…”

Synthesis of exocyclic α,β-unsaturated ketones

“…94,100,125 In this way both diastereomers became available as starting materials for the preparation of polycyclic organic compounds. …”