| 摘要 |
PURPOSE:To obtain a new compound having high refractive index and high Abbe number and useful as a raw material for optical materials. CONSTITUTION:The compound of formula I [X is (CH2CH2S)n2-H; n1 is 1-5; n2 is 0-2], e.g. 2,5-bis(2-mercaptoethylthiomethyl)-1,4-dithiane. The compound of formula I can be produced by reacting diallyl disulfide of formula II with bromine, cyclizing and dimerizing the product, reacting the obtained brominated compound with thiourea to obtain an isothiuronium salt of formula III, hydrolyzing the compound of formula III and finally acidifying the reactional system with hydrochloric acid. The optical material derived from the compound of formula I exhibits high refractive index and low dispersion and has excellent heat-resistance, weather resistance and transparency and, accordingly, it is useful as optical products such as lens and prism (e.g. glasses and camera lens), optical fiber, substrate for recording medium for optical disk, magnetic disk, etc., color filter, infrared absorption filter, etc. |
