Dohi Toshifumi
Graduate School of Pharmaceutical Sciences, Osaka University, Suita City, Japan.
Yakugaku Zasshi. 2006 Sep;126(9):757-66. doi: 10.1248/yakushi.126.757.
We have synthesized a novel, nonpolymer-supported recyclable hypervalent iodine (III) reagent, 1,3,5,7-tetrakis[4-(diacetoxyiodo)phenyl]adamantane 3a and its derivatives 3b, c and utilized them in environmentally benign oxidations. The new reagents 3a-c mediate a wide range of oxidative transformations with efficiencies similar to those of conventional reagents, phenyliodine (III) diacetate (PIDA), pheyliodine (III) bis (trifluoroacetate) (PIFA), and (hydroxyl(tosyloxy)iodo). benzene (HTIB), and have higher reactivity compared with polymer-supported recyclable reagents such as poly(diacetoxyiodo)styrene (PDAIS) and poly{bis(trifluoroacetoxy)iodo}styrene (PBTIS). In all cases, tetraiodide 4 was recovered nearly quantitatively in a pure form after simple workup, i.e., filtration. Reoxidation of 4 to 3a with m-chloroperbenzoic acid also proceeded quantitatively, without loss of oxidative activity. Recyclable 3a-c are used in various organic solvents as well as water, and thus mild and clean oxidation of alcohols in water has been achieved using 3a. A facile synthesis of aldehydes from primary alcohols has also been demonstrated using a dual recycling strategy, with 3a and recyclable 2,2,6,6-tetramethyl-1-piperidinyloxy free radical (TEMPO).
我们合成了一种新型的、非聚合物负载的可回收高价碘（III）试剂1,3,5,7-四[4-(二乙酰氧基碘)苯基]金刚烷3a及其衍生物3b、c，并将它们用于环境友好型氧化反应中。新型试剂3a-c介导了多种氧化转化反应，其效率与传统试剂二乙酸碘苯（PIDA）、双（三氟乙酸）碘苯（PIFA）和（羟基（对甲苯磺酰氧基）碘）苯（HTIB）相似，并且与聚合物负载的可回收试剂如聚（二乙酰氧基碘）苯乙烯（PDAIS）和聚{双（三氟乙酰氧基）碘}苯乙烯（PBTIS）相比具有更高的反应活性。在所有情况下，经过简单的后处理，即过滤，几乎可以定量回收纯的四碘化物4。用间氯过苯甲酸将4再氧化为3a的反应也能定量进行，且不会损失氧化活性。可回收的3a-c可在各种有机溶剂以及水中使用，因此使用3a已实现了在水中对醇类进行温和且清洁的氧化。还使用3a和可回收的2,2,6,6-四甲基-1-哌啶氧基自由基（TEMPO）通过双重回收策略证明了从伯醇简便合成醛的方法。
