A silver(I)-catalyzed reaction of 2-alkynylbenzaldoxime with arylsulfonyl chloride

A silver-catalyzed reaction of 2-alkynylbenzaldoxime with arylsulfonyl chloride proceeds smoothly at room temperature to afford 4-tosyloxyisoquinolines in moderate to good yields. Additionally, the resulting 4-tosyloxyisoquinolines could be further elaborated through palladium-catalyzed coupling reactions leading to diverse isoquinolines.     

A silver(I)-catalyzed tandem reaction of 2-alkynylbenzaldoxime with alkylidenecyclopropane

A silver(I)-catalyzed tandem reaction of 2-alkynylbenzaldoxime with alkylidenecyclopropane gives rise to benzo-7-azabicyclo[4.2.2]dec-7-en-4-ones in moderate to good yields. The complexity and diversity could be easily incorporated with the formation of three bonds during the process.     

Synthesis of 2-(polyfluoroaryl)benzofurans via a copper(I)-catalyzed reaction of 2-(2,2-dibromovinyl)phenol with polyfluoroarene

A novel and efficient route for the synthesis of 2-(polyfluoroaryl)benzofurans via a copper(I)-catalyzed tandem reaction of 2-(2,2-dibromovinyl)phenol with polyfluoroarene is reported. The corresponding products are generated in good yields. During the reaction process, a copper-catalyzed intramolecular C-O bond formation and a C-H activation are involved.     

Library construction of 1-(1H-imidazol-1-yl)-1,2-dihydroisoquinolines via three-component reaction of 2-alkynylbenzaldehyde, amine, and imidazole

Parallel diversity-oriented synthesis of diverse 1-(1H-imidazol-1-yl)-1,2-dihydroisoquinolines via AgOTf-catalyzed three-component reaction of 2-alkynylbenzaldehyde, amine, and imidazole is described. This reaction works efficiently under mild conditions to generate a small library of imidazole-incorporated 1,2-dihydroisoquinolines.     

Synthesis of 1,2-dihydroisoquinolines via palladium(0)-catalyzed addition-cyclization of chloroform to ortho-alkynylaldimines

Addition-cyclization of chloroform to ortho-alkynylaldimines proceeded in the presence of PdCl₂(PPh₃)₂/dppe or Pd₂dba₃·CHCl₃/dppe at 100 °C to afford the corresponding 1-(trichloromethyl)-1,2-dihydroisoquinolines in good to high yields.     

Rh(I)-catalyzed Pauson-Khand reaction of 1-phenylsulfonyl-1,2-octadien-7-yne derivatives

The Rh(I)-catalyzed PKR of 1-phenylsulfonyl-1,2-octadien-7-ynes and their aza derivatives exclusively produced the corresponding 9-phenylsulfonylbicyclo[4.3.0]nona-1,6-dien-8-ones and no 4-(phenylsulfonylmethylidene)bicyclo[3.3.0]oct-1-en-3-ones could be detected. Thus, the ring-closing pattern was found to be the same as those of the previously reported 3-phenylsulfonyl-1,2-octadien-7-yne derivatives. However, the formation of 4-(phenylsulfonylmethylidene)-7-oxabicyclo[3.3.0]oct-1-en-3-ones was observed as a minor product when the 5-oxa congeners were used. In addition, a larger ring-sized product, 10-phenylsulfonyl-5-azabicyclo[5.3.0]deca-1,7-dien-9-one derivative, was obtained from the 6-aza derivative of 1-phenylsulfonyl-1,2-nonadien-8-yne.     

Rh(I)-catalyzed addition of alkenylzirconocene chlorides to aldimine derivatives

[RhCl(COD)]₂ (2 mol%) catalyzed reactions of alkenylzirconocene chloride complexes to N-Ts, -PO(OEt)₂ and COOR aldimine derivatives were efficiently carried out in dioxane at room temperature to give allylic amine derivatives in excellent yields. This is the first example of the catalytic addition reactions of alkenylzirconocene chloride complexes to aldimine derivatives.     

A facile route to the pentacyclic lamellarin skeleton via Grob reaction between 3-nitro-2-(trifluoromethyl)-2H-chromenes and 1,3,3-trimethyl-3,4-dihydroisoquinolines

The basic structural framework of lamellarin alkaloids, 8,9-dihydro-6H-chromeno[4′,3′:4,5]pyrrolo[2,1-a]isoquinoline derivatives, has been obtained in good yields via Grob reaction between 3-nitro-2-(trifluoromethyl)-2H-chromenes and 1,3,3-trimethyl-3,4-dihydroisoquinolines in refluxing isobutanol. When the reaction was carried out in toluene at room temperature, only Michael adducts, as a mixture of two diastereomers, were isolated.     

Diversity-oriented approach to 1,2-dihydroisoquinolin-3(4H)-imines via copper(I)-catalyzed reaction of (E)-2-ethynylphenylchalcone, sulfonyl azide and amine

A three-component reaction of (E)-2-ethynylphenylchalcone, sulfonyl azide, and amine catalyzed by copper(I) chloride (5 mol%), in the presence of triethylamine, under mild conditions is described. This transformation proceeds efficiently to generate 1,2-dihydroisoquinolin-3(4H)-imines in good to excellent yields.     

Reaction of trimethyl (bromomagnesiumethynyl)silane with organyltrialkoxysilanes

Conclusions The reaction of trimethyl(bromomagnesiumethynyl)silane with organyltrialkoxysilanes gave a series of organyl(trimethylsilylethynyl)dialkoxysilanes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2637–2640, November, 1985.     

Trifluoromethylation of non-activated aldimines with trimethyl(trifluoromethyl)silane in the presence of tetramethylammonium fluoride: A closer look into the reaction route

The reactions of non-activated aldimines with trimethyl(trifluoromethyl)silane and 1 equiv. of tetramethylammonium fluoride proceed via the formation of tetramethylammonium amides which were identified by low-temperature ¹⁹F NMR experiments. Consecutive reactions of the salts formed in situ with electrophiles yielded trifluoromethylated amines. Fluoride elimination is observed in the absence of electrophilic substrates leading to the formation of difluoromethylated ketimines.     

First example of regioselective nucleophilic 1,6-addition of trimethyl(trifluoromethyl)silane to 4H-chromene derivatives

Condensation of 2-trifluoromethylchromone with diethyl malonate, ethyl cyanoacetate, and Meldrum’s acid gave the corresponding methylidene derivatives of 2-trifluoromethyl-4H-chromene. Nucleophilic 1,6-addition of an excess of Me₃SiCF₃ in the presence of Me₄NF to those obtained from the former two compounds afforded 4-substituted 2,2-bis(trifluoromethyl)-2H-chromenes. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1628–1630, September, 2006.     

Dendronized diruthenium compounds via the copper(I)-catalyzed click reaction

Novel Ru2-containing dendritic compounds were prepared from the CuI-catalyzed 1,3-dipolar cycloaddition between Ru2 compounds containing one or two ethynes, Ru2(D(3,5-Cl2Ph)F)4-n(DMBA-4-C2H)n with n=1 and 2, and azidopoly(benzyl ether) dendrons. These new compounds were also characterized with X-ray diffraction and voltammetric techniques.     

Gold(I)-catalyzed glycosidation of 1,2-anhydrosugars

Being able to increase the yield by >20% compared to the conventional use of anhydrous zinc chloride (>1 equiv) as a promoter, Ph 3PAuOTf is disclosed to be a superior catalyst for the well-established glycosylation reaction with 1,2-anhydrosugars as donors.     

Oxidative dimerization of azoles via copper(II)/silver(I)-catalyzed CH homocoupling

When several azole derivatives such as imidazole, thiazole, and oxazole are treated with a catalyst system of copper(II)/silver(I) under oxygen atmosphere, oxidative dimerization at the CH bond of the 2-position takes place to afford the corresponding bisazoles up to 86% yield.     

An efficient approach to fused indolines via a copper(I)-catalyzed reaction of sulfonyl azide with 2-ethynylaryl methylenecyclopropane

A cascade reaction of 2-ethynylaryl methylenecyclopropane with sulfonyl azide catalyzed by copper(I) iodide under mild conditions is described, which provides a novel and efficient route for the generation of fused indolines.     

Enantioselective total synthesis of (+)-asteriscanolide via Rh(I)-catalyzed [(5+2)+1] reaction

The total synthesis of (+)-asteriscanolide starting from two commercially available materials has been accomplished in 19 steps with a 3.8% overall yield. The key reaction is a chiral ene-vinylcyclopropane substrate induced Rh(I)-catalyzed [(5+2)+1] cycloaddition that efficiently constructs the [6.3.0] carbocyclic core with complete asymmetric induction.