The preparation and characterization of the following trifluoromethylated carotenoids are reported: 9-CF3–, 13-CF3–, 9,9′-bis-CF3–, 13,13′-bis-CF3–β-carotene, 9-CF3– and 13-CF3–canthaxanthin, 13′-CF3– and, 9′-CF3–4-oxo-β-carotene, 13′-CF3–adonirubin and 3-dehydro-13′-CF3–canthaxanthin. The CF3 group exhibits a strong cis-directing effect leading primarily to the cis isomer (near the CF3 group, i.e
报告了以下三
氟甲基化类
胡萝卜素的制备和表征:9-CF 3 –,13-CF 3 –,9,9'-bis-CF 3 –,13,13'-bis-CF 3 –
β-胡萝卜素,9 -CF 3 –和13-CF 3 –
角黄素,13'-CF 3 –以及9'-CF 3 –4-氧代-
β-胡萝卜素,13'-CF 3 –
鸟嘌呤和3-dehydro-13'-CF 3 –
角黄素。CF 3基团表现出很强的顺式导向作用,主要导致合成混合物中的顺式异构体(接近CF 3基团,即all- E)。未成年人反式异构体可通过敏化辐射富集;然而,发现它们在室温下仅略微稳定。CF 3基团还表现出对氧化反应的稳定作用。报告了这些
氟化类
胡萝卜素的光谱数据和氧化电位。