冠醚螺吡喃化合物的合成和光致变色性质

合成了四个新的6位带不同取代基的含冠醚结构单元吲哚啉螺苯并吡喃化合物(5a-5d),研究了其光致变色性质和离子诱导光致变色作用及取代基的影响。结果表明冠醚能稳定螺吡喃开环形式,碱金属离子对冠醚螺吡喃的生色有诱导作用;6位为吸电子基团时,螺吡喃开环形式的稳定性增加,而6位为推电子基团时,螺吡喃开环形式的稳定性降低。另外,就稳定螺吡喃开环体的作用来说,吲哚啉环上的取代基效应和苯并吡喃环上的正好相反。

Syntheses and photochromic properties of crowned spirobenzopyrans

Four novel crowned spirobenzopyrans containing different substituent at 6 - position (5a - 5d) were prepared by the condensation of monoazabenzo - 15 - C - 5(4) with the spirobenzopyrans(3a - 3d) , which were obtained by aldol - type reaction of the Fischer's base(2) with salicylicaldehyde (1a- 1d) . Their photochromic, cation induced photochromic properties and substituent effect have been investigated. The results show that crowned ether can stabilize the open - forms of spirobenzopyrans, and that alkali - metal cations can induce the isomerization of crowned spirobenzopyrans. The electron with drawing groups at 6 - position can increase the stability of open - forms of spirobenzopyrans, but the electron donating groups reduce their stability. In additon, the substituent effect in indoline ring is in opposition to that in benzopyran ring as to stabilizing open - form of indolinospirobenzopyran.