Ring-Opening Metathesis Polymer Sphere-Supported <i>s</i><i>eco</i>-Porphyrazines: Efficient and Recyclable Photooxygenation Catalysts
作者:Matthew J. Fuchter、Brian M. Hoffman、Anthony G. M. Barrett
DOI:10.1021/jo052156t
日期:2006.1.1
subsequently converted into its zinc seco-derivative. Polymerization gave the corresponding ROMPgel and ROMPsphere (ROMP = ring-opening metathesis polymer) reagents, the latter of which proved efficient as an immobilized catalyst for the sensitized production of singlet oxygen for the purification-minimized parallelsynthesis of endoperoxides and ene adducts.
Palladium-Catalyzed Cyclopropanation of Unsaturated Endoperoxides. A New Peroxide-Preserving Reaction
作者:Michael A. Emerzian、William Davenport、Jiangao Song、Jim Li、Ihsan Erden
DOI:10.1002/adsc.200800804
日期:2009.5
Unsaturated bicyclic endoperoxides are efficiently cyclopropanated with excess diazomethane in the presence of catalytic Pd(OAc)2 in a stereoselective manner. This method represents a new peroxide preserving transformation. Whereas the unsaturated endoperoxides in the [2.2.1] series are attacked by the carbene from the exo face, the analogs with larger bridges are preferentially attacked from the face
Triphenylphosphine Reduction of Saturated Endoperoxides
作者:Ihsan Erden、Christian Gärtner、M. Saeed Azimi
DOI:10.1021/ol901652u
日期:2009.9.3
Triphenylphosphinereduction of saturated endoperoxides derived from 6,6-dimethylfulvene and spiro[2.4]hepta-4,6-diene in the presence of nucleophiles results in the formation of products that mainly stem from deoxygenation followed by carbocation formation. Nucleophilic attack by solvent proceeds by an SN1 like mechanism; allyl shifts and cyclopropylcarbinyl-cyclobutyl rearrangements also occur. With
在亲核试剂存在下,衍生自 6,6-二甲基富烯和螺 [2.4] 庚-4,6-二烯的饱和内过氧化物的三苯基膦还原导致产物的形成,这些产物主要源于脱氧,然后是碳正离子的形成。溶剂的亲核攻击通过类似S N 1 的机制进行;烯丙基转移和环丙基羰基-环丁基重排也会发生。由于系统缺乏碳正离子稳定基团,脱氧步骤之前是 H 2 O攻击磷。
Face selectivity in the reduction with dideuteriodi-imide of endoperoxides derived from the singlet oxygenation of cycloalka-1,3-dienes
作者:A. J. Bloodworth、Henny J. Eggelte
DOI:10.1039/p29840002069
日期:——
Four dioxabicyclo[n.2.2]alkenes (n= 1–4) have been reduced with dideuteriodi-imide. For each reduction, the ratio of the amount of product arising from cis-addition of two deuterium atoms to the face of the double bond syn to the dioxygen bridge to that arising from addition to the anti face has been determined by 1H-decoupled 2H n.m.r. spectroscopy, and the structures of the individual isomers have
双二碘二酰亚胺已还原了四个二氧杂双环[ n .2.2]烯烃(n = 1-4)。对于每一个减少,产品的从所产生的量的比率的顺式2个氘原子的-addition双键的面顺向双氧桥到从除了所产生的反面已被确定1个H-去耦2 H nmr光谱学和单个异构体的结构已通过1 H nmr光谱学确定。环戊二烯内过氧化物(n = 1)仅产生反异构体,而环己二烯内过氧化物(n= 2)得到含有66%顺式异构体的混合物,而环庚二烯和环辛二烯内过氧化物(n= 3和4)仅给出顺式异构体。结果与整个系列在电子和空间效应方面的预期变化一致。