Various α-Oxygen Functionalizations of β-Dicarbonyl Compounds Mediated by the Hypervalent Iodine(III) Reagent<i>p</i>-Iodotoluene Difluoride with Different Oxygen-Containing Nucleophiles
作者:Jun Yu、Jun Tian、Chi Zhang
DOI:10.1002/adsc.200900737
日期:2010.2.15
for the effective introduction of variousoxygen-containing functionalities including tosyloxy, mesyloxy, acetoxy, phosphoryloxy, methoxy, ethoxy and isopropoxy at the α-position of β-dicarbonyl compounds. These transformations can be readily realized by the use of the combined reagent of p-iodotoluene difluoride and variousoxygen-containing nucleophilic compounds such as p-toluenesulfonic acid, methanesulfonic
p -Iodotoluene二氟乙烯(p -Tol-IF 2)已被发现是一种一般用于有效地引入各种含氧官能团包括甲苯磺酰氧基,甲磺酰氧基,乙酰氧基,磷酰甲氧基,乙氧基和异丙氧基在α位的试剂β-二羰基化合物。通过使用对-碘甲苯二氟化物和各种含氧亲核化合物如对甲苯磺酸,甲磺酸,乙酸,磷酸二苯酯,甲醇,乙醇和丙-2-醇的组合试剂,可以轻松实现这些转化。分别在温和的条件下。并且,原位生成的高价碘(III)物种通过在这种转化中,对-碘甲苯二氟化物与相应的含氧亲核试剂之间的配体交换被认为是真正的氧化剂。
Hypervalent iodine(III)-induced methylene acetoxylation of 3-oxo-N-substituted butanamides
作者:Wei-Bing Liu、Cui Chen、Qing Zhang、Zhi-Bo Zhu
DOI:10.3762/bjoc.7.167
日期:——
l acetate derivatives were synthesized through an acetoxylation process to methylene with the aid of (diacetoxyiodo)benzene (DIB) as the oxidant. Not only mild reaction conditions, but also excellent yields and good substrate scope make the present protocol potentially useful in organicsynthesis.
The Reactions of β-Hydroxychalcones and 2-Acetoxy-1,3-diarylpropan-1,3-diones with Lead Tetraacetate
作者:Kazu Kurosawa、Akira Moriyama
DOI:10.1246/bcsj.47.2717
日期:1974.11
The reaction of β-hydroxychalcone with leadtetraacetate gave benzil. The reaction of 4,4′-dimethoxy-β-hydroxychalcone gave 2-acetoxy-1,3-di(p-methoxyphenyl)propan-1,3-dione and 4,4′-dimethoxybenzil. The reactions of 2-acetoxy-1,3-diarylpropan-1,3-diones yielded 2,2-diacetoxy-1,3-diarylpropan-1,3-diones and benzils respectively. The formation of the benzils from β-hydroxychalcones and 2-acetoxy-1,3-diarylpropan-1
The Decarbonylation of Diphenyl Triketone<sup>1</sup>
作者:John D. Roberts、Donald R. Smith、C. C. Lee
DOI:10.1021/ja01146a037
日期:1951.2
of the characteristic reactions of α-polycarbonyl compounds is their tendency to undergo “decarbonylation” with the formation of a compound with one less carbon atom and carbonmonoxide or carbon dioxide. An important synthetic example of this type of reaction is the thermal decomposition of oxalylacetic esters which yield the corresponding malonic esters and carbonmonoxide. The related thermal decarbonylation
A simple method for α‐hydroxylation of a β‐oxime ester has been developed, which involves an oxidative α‐acetoxylation using PhI(OAc)2 with a catalyticamount of Sc(OTf)3 or Sc2O3‐TMSOTf, followed by careful hydrolysis. The ScIII salt acts as an excellent reusable catalyst in this system.
已开发出一种简单的方法使β-肟酯发生α-羟基化反应,该方法包括使用PhI(OAc)2和催化量的Sc(OTf)3或Sc 2 O 3- TMSOTf氧化α-乙酰氧基化反应,随后进行小心水解。Sc III盐在该系统中可作为极好的可重复使用的催化剂。