Biomimetic Cyclization of Small Terpenoids Promoted by Zeolite NaY: Tandem Formation of α-Ambrinol from Geranyl Acetone
作者:Constantinos Tsangarakis、Manolis Stratakis
DOI:10.1002/adsc.200505059
日期:2005.7
ZeoliteNaYpromotes efficiently the biomimeticcyclization of small acyclic terpenes. Geranyl and neryl acetone undergo a novel tandem 1,5-diene cyclization/carbonyl-ene reaction to form the natural product α-ambrinol isolated in >65% yield.
Electrophilic cyclization of α- and β-geranyl acetates by mercury(II) trifluoroacetate
作者:V. N. Kulchitski、N. D. Ungur、P. F. Vlad
DOI:10.1007/bf02495925
日期:1997.7
Electrophilic cyclization of β-geranyl acetate promoted by mercury(II) trifluoroacetate leads to mixtures of α- and γ-5αH-cyclogeranyl acetate derivatives and 6α-hydroxy-5αH-and 6α-hydroxy-5βH-cyclogeranyl acetate derivatives mercurated at the C-3 atom. The ratio of the unsaturated and hydroxymercurated products depends on the reaction conditions. α-Geranyl acetate reacts with mercury(II) trifluoroacetate
由三氟乙酸汞 (II) 促进的 β-香叶基乙酸酯的亲电环化导致 α- 和 γ-5αH-环香叶基乙酸酯衍生物与 6α-羟基-5αH-和 6α-羟基-5βH-环香叶基乙酸酯衍生物的混合物在 C- 3 原子。不饱和和羟基汞化产物的比例取决于反应条件。α-香叶基乙酸酯与三氟乙酸汞 (II) 反应生成 6α-羟基-5αH-和 6α-羟基-5βH-香叶基乙酸酯的混合物,在 C-9 处汞化,在 C-4 处具有赤道亚甲基汞基。含汞环香叶基衍生物中的含汞基团很容易被含氧官能团还原或取代;这构成了难以获得的多官能环香叶基衍生物的便捷途径。
Y-Zeolite-Catalyzed Cyclizations of Terpenols
作者:Wei Yu、Fengling Bian、Yuan Gao、Li Yang、Zhong-Li Liu
DOI:10.1002/adsc.200505146
日期:2006.1
Depending on the metal doped and the activation temperature, Y-zeolites can catalyze a diversity of reactions of geraniol (1), linalool (2) and nerol (3). Compound 1 can be transformed to α- and/or γ-cyclogeraniol (4 and 5) highly efficiently.