4,8,8-Tribromobicyclo[5.1.0]oct-4-en-3-ones from dibromocarbene adducts of cyclohexa-1,4-dienols
作者:A. K. Yagoub、George M. Iskander
DOI:10.1039/p19750001043
日期:——
Treatment of the bisdibromocarbene adducts (I) of substituted cyclohexa-1,4-dienols with pyridine or triethylamine gave α-bromo-αβ-unsaturated ketones (II) in good yields. The dihydroxy-diadduct (I; R1= H, R2= OH) gave the cyclo-octatrienone (IV), whereas the isomeric diadduct (I; R1= OH, R2= H) gave 3-bromo-4-hydroxybenzocyclobuten-1(2H)-one (VIII) in poor yield.
用吡啶或三乙胺处理取代的环己-1,4-二烯醇的双二溴卡宾加合物(I),可得到高产率的α-溴-αβ-不饱和酮(II)。二羟基二价产物(I; R 1 = H,R 2 = OH)给出了环八碳三烯酮(IV),而异构二元产物(I; R 1 = OH,R 2 = H)得到了3-溴-4-羟基苯并环丁烯-1(2 H)-一(VIII)收率不佳。
New methods and reagents in organic synthesis, 40. Amination of aromatic and heteroaromatic organometallics using diphenyl phosphorazidate (DPPA)
Amination of aromatic and heteroaromatic organometallics is efficiently achieved by sequential treatment with diphenylphosphorazidate (DPPA) and sodium bis(2-methoxyethoxy)aluminum hydride in a one-pot process.
Two series of oligo(phenyleneethynylene)s (OPEs) with different dendrimer side groups have been designed and synthesized. The molecules contain thiol groups at both ends to enable interconnection between nanoscale gapped metallic electrodes. The different dendrimer groups act as "shells", allowing tailoring to the nanoscopic environment surrounding the OPE "core". Meanwhile, the dendrimer shells also
Meroterpenes are compounds of mixed biogenesis, isolated from plants, microorganisms and marine invertebrates. We have previously isolated and determined the structure for a series of meroterpenes extracted from the ascidian Aplidium aff. densum. Here, we demonstrate the chemical synthesis of three of them and their derivatives, and evaluate their biological activity on two bacterial strains, on sea urchin eggs, and on cancerous and healthy human cells.
Synthesis of Polyisoprene Terpenoid Dendrons and their Applications in Oligo(phenylene ethynylene)s as “Shells”
作者:Wen-Yu Chai、Zi-Fa Shi、Peng An、Wei Wang、Lu-Feng Wang、Xiao-Ping Cao
DOI:10.1002/asia.201100480
日期:2012.1.2
functionality, followed by deoxygenation of the resulting tertiary alcohol by triethylsilane and trifluoroacetic acid, then hydrogenation or hydrogenolysis. The dendrons were also attached to oligo(phenyleneethynylene)s (OPEs) so as to function as protective shells to allow fine tuning of the nanoscopic environment around the OPE moiety, and to exert precise control of the packing density and intermolecular
描述了新型聚异戊二烯萜类化合物(PIPTP)树突的新型双阶段收敛合成。PIPTP树突具有高度分支的脂族烃骨架和亲水性羟基焦点功能。这些树突具有特定的公式C (5×2 G + 1 -5) H (5×2 G + 2-8)O,并且每个树突层由异戊二烯单元构成。关键的支化步骤包括将烷基金属加成双酯官能团,然后通过三乙基硅烷和三氟乙酸对所得的叔醇进行脱氧,然后进行氢化或氢解。树突还连接到低聚(亚苯基乙炔基)(OPE)上,以用作保护壳,以允许微调OPE部分周围的纳米环境,并精确控制OPE的堆积密度和分子间相互作用核心。荧光量子产率数据表明,与Fréchet树突相比,PIPTP树突对OPE核的封装更好。