| 摘要 |
NEW MATERIAL:A compound expressed by formula I [R1 and R2 are 1-18C alkyl, one or two or more nonadjacent methylenes in the aforementioned alkyl may be substituted with X (X is O or S), X-C(O), C(O), C(Y)H (Y is halogen), CH=CH, etc.; A is single bond or formula II to V (Z is F, Cl, CN, etc.), etc.]. EXAMPLE:2-(p-Octyloxyphenyl)-5-hexylbenzoselenazole. USE:Liquid crystal display elements, liquid crystal-optical shutters, etc. PREPARATION:A compound expressed by formula VI is allowed to react with NaNO2, AcONa and KSeCN to provide a compound expressed by formula VII, which is then reacted with NaOH/MeOH and further with Zn/HCl to afford a compound expressed by formula VIII. The resultant compound expressed by formula VIII is then reacted with a compound expressed by formula IX. |
