4-芳亚甲基-2-羟基-3-蒎酮类化合物的合成及其紫外吸收特征研究

Synthesis and Ultraviolet Absorption Characteristics of 4-Arylidene-2-hydroxy-3-pinanones

以(-)-α-蒎烯为原料合成了系列新型4-芳亚甲基-2-羟基-3-蒎酮类化合物.(-)-α-蒎烯经选择性氧化得到(+)-2-羟基-3-蒎酮;在碱催化作用下,(+)-2-羟基-3-蒎酮与苯甲醛、对甲基苯甲醛、对甲氧基苯甲醛、对羟基苯甲醛、对氯苯甲醛、对硝基苯甲醛和糠醛等芳香醛缩合,得到系列光学活性4-芳亚甲基-2-羟基-3-蒎酮类化合物a～g.采用1H NMR,13C NMR,GC-MS和FT-IR等分析手段对合成所得4-芳亚甲基-2-羟基-3-蒎酮类化合物的结构进行了表征,考察了它们的紫外吸收特性及光稳定性.结果表明,化合物a,b,e对UVB具有良好的吸收性能;而化合物c,d,f,g兼具长波紫外线(UVA)和中波紫外线(UVB)的吸收性能.化合物a～g的光稳定性顺序为d>c>e>f>b>a>g.

A new series of 4-arylidene-2-hydroxy-3-pinanones were synthesized from （--）-a-pinene. （＋）-2-Hydroxy- 3-pinanone was obtained from （--）-a-pinene by selective oxidation with potassium permanganate, and it was reacted with aromatic aldehydes including benzaldehyde, p-methylbenzaldehyde, p-methoxybenzaldehyde, p-hydroxybenzaldehyde, p-chlorobenzaldehyde, p-nitrobenzaldehyde, and furfural catalyzed with alkali catalysts to get optical activity 4-arylidene-2-hydroxy-3-pinanones aug. The structures of a^g were identified by means of IH NMR, 13C NMR, GC-MS and FT-IR techniques, and their ultraviolet absorption characteristics and light stabilities were also investigated. The results showed that compounds a, b and e exhibit good absorbency as the UV-B-type absorbents, and compounds e, d, f and g had both functions as long-wave ultraviolet （UVA） and medium-wave ultraviolet （UVB） absorbents. The light stability sequence of these compounds was d 〉 c 〉 e 〉 f〉 b 〉 a 〉 g.