Cycloisomerization between Aryl Enol Ether and Silylalkynes under Ruthenium Hydride Catalysis: Synthesis of 2,3-Disubstituted Benzofurans
摘要:
Metal-catalyzed cycloisomerization reactions of 1,n-enynes have become conceptually and chemically attractive processes in the search for atom economy, which is. a key subject of current research. However, metal-catalyzed cycloisomerization between aryl enol ether and silylalkynes has not been developed. The ruthenium hydride complex catalyzed cycloisomerization between aryl enol ether and silylalkynes is reported to give benzofurans having useful functional groups, vinyl and trimethylsilylmethyl, on the 2- and 3-positions, respectively.
One-Pot Synthesis of 5-Amino-2,5-dihydro-1-benzoxepines: Access to Pharmacologically Active Heterocyclic Scaffolds
作者:Ewen D. D. Calder、Salaheddin A. I. Sharif、Fiona I. McGonagle、Andrew Sutherland
DOI:10.1021/acs.joc.5b00583
日期:2015.5.1
A one-pot multibond-forming process involving a thermally mediated Overman rearrangement and a ring closing metathesis reaction of allylic trichloroacetimidates bearing a 2-allyloxyaryl group has been developed for the synthesis of 5-amino-substituted 2,5-dihydro-1-benzoxepines. Chemoselective reduction and functionalization of these compounds allowed access to a range of pharmacologically active 5-amino-2
The Synthesis of 5-Amino-dihydrobenzo[<i>b</i>]oxepines and 5-Amino-dihydrobenzo[<i>b</i>]azepines via Ichikawa Rearrangement and Ring-Closing Metathesis
The combination of Ichikawa’s rearrangement and a ring-closing metathesis reaction of allyl carbamates is presented as a method for the preparation of 5-amino-substituted 2,5-dihydro-benzo[b]oxepines, 2,5-dihydro-benzo[b]azepines, and 2,5-dihydro-benzo[b]thiepins. It was demonstrated that the use of nonracemic allyl carbamates enables the synthesis of enantioenriched benzo-fused seven-membered heterocycles
市川的重排和烯丙基氨基甲酸酯的闭环复分解反应的组合是作为用于制备5-氨基-取代的2,5-二氢-苯并[方法b ] oxepines,2,5-二氢-苯并[ b ] zepines和2,5-二氢-苯并[ b ]噻吩类。已经证明,使用非外消旋的烯丙基氨基甲酸酯能够合成对映体富集的苯并稠合的七元杂环。最后,显示了所获得结构的进一步功能化允许获得具有药理活性的5-氨基取代的2,3,4,5-四氢-1-苯并[ b ]奥沙平支架。
K<sub>2</sub>S<sub>2</sub>O<sub>8</sub>-Mediated Selective Trifluoromethylacylation and Trifluoromethylarylation of Alkenes under Transition-Metal-Free Conditions: Synthetic Scope and Mechanistic Studies
on and -arylation of alkenes with inexpensive CF3SO2Na and K2S2O8 in aqueous media has been developed, respectively, affording the highly chemoselective synthesis of CF3-functionalized chroman-4-ones and chromanes in satisfactory yields. Control experiments and DFT calculations indicate that the CF3SO2Na/K2S2O8 system is capable of trifluoromethylating the substrate of alkenes without a transition
Silver-Catalyzed Radical Cascade Cyclization toward 1,5-/1,3-Dicarbonyl Heterocycles: An Atom-/Step-Economical Strategy Leading to Chromenopyridines and Isoxazole-/Pyrazole-Containing Chroman-4-Ones
A novel and convenient silver-catalyzed radicalcascadecyclizationtoward a large variety of 1,5-/1,3-dicarbonyl heterocycles containing a chroman-4-one, indanone, or 2,3-dihydroquinolin-4(1H)-one moiety was developed, by reacting various 2-functionalized benzaldehydes, including 2-allyloxy benzaldehydes, 2-allyl benzaldehyde, and 2-N(Ts)CH2–CH═CH2 substituted benzaldehyde, with 1,3-dicarbonyl compounds
一种新颖且方便的银催化自由基级联环化反应,形成多种多样的含苯并二氢吡喃-4-酮,茚满酮或2,3-二氢喹啉-4(1 H)-的1,5- / 1,3-二羰基杂环部分被开发,通过各种2官能苯甲醛,包括2-烯丙氧基苯甲醛,2-烯丙基苯甲醛,和2-N(Ts)的CH反应2 -CH = CH 2取代的苯甲醛,在存在1,3-二羰基化合物AgNO 3 / K 2 S 2 O 8的在温和的反应条件下放入一锅中。新获得的含1,5- / 1,3-二羰基的杂环进一步直接用于合成结构上更多样化的多杂环,主要包括色吡啶和含异恶唑或吡唑的苯并二氢吡喃-4-酮。