Makoto Ishihara

The synthesis of a tricyclic hydroazulenone from exo-epoxygermacrene-Din connection with periplanone A

Abstract In connection with periplanone A, acid-catalyzed reaction of germacrene-D epoxide has been carried out using AlCl 3 in ether to afford a hydroazulene which has been further transformed into one of the hydroazulenones proposed to be periplanone A.

5-BENZYLIDENEOXAZOLIDINE-2, 4-DIONES AS NEW ORGANIC NLO COMPOUNDS

ABSTRACT As nonlinear optical(NLO) material for blue light, second harmonic generaton(SHG) devices, 5-benzylideneazolidine-2, 4-diones were studied. The highest blue light transparency was observed with 5-(4-Methoxybenzylidene)-3-propyloxazolidine-2, 4-dione, which had a λcutoff of 383nm showing an SHG activity. The β value of 35 .9×10−30 esu was calculated by PPP-CI method, which is fairly large compared with β=27.5×10−3O esu for 3,5-dimethyl-l-(4-nitrophenyl)pyrazole[DMN P]. Another SHG active compound, 3-ethyl-5-(3,4-methylenedioxyben-zylidene)oxazolidine-2,4-dione was investigated by X-ray crystalography. The nonlinear optical constants calculated by oriented-gas model were d21=15.9pm/V, d22=177.6pm/V and d23=52.4pm/V. These results show that 5-benzylidene-2,4-diones have high potentials for nonlinear optical materials suitable for blue light SHG devices.