A series of substituted vinylidene-naphthofurans were prepared from 2-naphthols. These compounds show both acido- and photochromism, at room temperature, developing different colorations that can be switched back to the initial uncolored state by the addition of base or removal of the light source. The introduction of electron-donating substituents in the right position leads to a significant bathochromic shift providing compounds that can generate brown/grey colors. These photoactive dyes were dispersed in polymeric materials proving photochromic materials that switch between the uncolored/colored states, in a few minutes, at room temperature.

中文翻译：

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使用亚乙烯基-萘呋喃实现灰色系光致变色材料

由2-萘酚制备一系列取代的亚乙烯基-萘呋喃。这些化合物在室温下均表现出酸致变色和光致变色现象，可显示出不同的颜色，可通过添加碱或去除光源将其切换回初始未着色状态。在正确的位置引入供电子性取代基会导致显着的红移，从而提供可以产生棕色/灰色的化合物。将这些光敏染料分散在聚合物材料中，证明光致变色材料可在室温下在几分钟内在无色/有色状态之间切换。