130602-11-8Relevant academic research and scientific papers
Annulation of Hydrazones and Alkynes via Rhodium(III)-Catalyzed Dual C-H Activation: Synthesis of Pyrrolopyridazines and Azolopyridazines
Streit, Andrew D.,Zoll, Adam J.,Hoang, Gia L.,Ellman, Jonathan A.
, p. 1217 - 1221 (2020)
Hydrazones readily synthesized from N-aminopyrroles or N-aminoazoles and aldehydes undergo Rh(III)-catalyzed dual C-H activation and coupling with aryl- A nd alkyl-substituted alkynes to give pyrrolopyridazines or azolopyridazines, respectively. This transformation represents a rare example of hydrazoyl C-H activation and proceeds without heteroatom functionality to direct C-H activation. Hydrazones derived from aromatic, alkenyl, and aliphatic aldehydes were effective inputs, and tethering the alkyne to the hydrazone enabled annulations to more complex, tricyclic products.
Synthesis of Tetrasubstituted Alkenes by Tandem Metallacycle Formation/Cross-Electrophile Coupling
Shimkin, Kirk W.,Montgomery, John
supporting information, p. 7074 - 7078 (2018/06/04)
Nickel-catalyzed cross-electrophile couplings have recently emerged as highly effective and practical methods for the formation of C-C bonds. By merging this process with well-established π-π coupling chemistry, a new method for the synthesis of tetrasubstituted alkenes has been developed. The procedure relies on the use of chlorosilanes as a means of generating reactive vinylnickel intermediates, which are capable of undergoing a reductive cross-electrophile coupling with alkyl halides. The method not only generates highly substituted allylic alcohol derivatives but also obviates the need for stoichiometric organometallic nucleophiles and provides greatly improved scope and functional group tolerance compared with previously developed methods.
Domino N2-Extrusion-Cyclization of Alkynylarylketone Derivatives for the Synthesis of Indoloquinolines and Carbocycle-Fused Quinolines
Akkachairin, Bhornrawin,Tummatorn, Jumreang,Khamsuwan, Narumol,Thongsornkleeb, Charnsak,Ruchirawat, Somsak
, p. 11254 - 11268 (2018/09/06)
New synthetic approaches for the synthesis of indoloquinolines and carbocycle-fused quinolines have been developed employing alkynylketone substrates. These synthetic transformations involved the application of N2-extrusion of azido complexes as a key step to generate carbodiimidium ion and nitrilium ion in situ, which further cyclized intramolecularly with alkyne via a domino process to provide indoloquinolines and carbocycle-fused quinolines, respectively, in moderate to good yields.
Triflic acid-catalyzed cascade cyclization of arenyl enynes via acetylene-cation cyclization and Friedel-Crafts type reaction
Jin, Tienan,Uchiyama, Junichi,Himuro, Masafumi,Yamamoto, Yoshinori
supporting information; scheme or table, p. 2069 - 2071 (2011/05/09)
A novel triflic acid-catalyzed cascade cyclization of arenyl 1,7-enynes through acetylene-cation cyclization followed by Friedel-Crafts reaction has been described. Various fused poly carbocycles can be obtained in good to high yields under mild reaction
Indium(III)-catalyzed coupling between alkynes and aldehydes to α,β-unsaturated ketones
Miura, Katsukiyo,Yamamoto, Kiyomi,Yamanobe, Aya,Ito, Keisuke,Kinoshita, Hidenori,Ichikawa, Junji,Hosomi, Akira
supporting information; experimental part, p. 766 - 767 (2011/01/09)
The combined use of a catalytic amount of InX3 (X = OTf and NTf2) and 1-butanol was found to be effective in formal alkynealdehyde metathesis. With this catalytic system, aromatic alkynes reacted with aromatic aldehydes to give chalcones in moderate to good yields. Alkynals were efficiently converted into 5- to 7-membered cyclic compounds by intramolecular alkyne-aldehyde coupling.
Rhodium-catalyzed intramolecular hydroacylation of 5- and 6-alkynals: Convenient synthesis of α-alkylidenecycloalkanones and cycloalkenones
Takeishi, Kenzo,Sugishima, Koudai,Sasaki, Kaori,Tanaka, Ken
, p. 5681 - 5688 (2007/10/03)
A novel intramolecular hydroacylation of 5- and 6-alkynals leading to α-alkylidenecycloalkanones was accomplished by using cationic a rhodium(I)/BINAP complex. For all cyclizations described, a single (E)-olefin isomer was obtained. At elevated temperature, hydroacylation and double bond migration of 5- and 6-alkynals proceeded in a one-pot reaction to give cycloalkenones. An intramolecular hydroacylation of a 7-alkynal was unsuccessful. This method represents an attractive new route to highly functionalized α-alkylidenecycloalkanones and cycloalkenones.
Iodotrimethylsilane-induced cyclization of 6-alkynal acetals
Takami,Yorimitsu,Shinokubo,Matsubara,Oshima
, p. 293 - 295 (2007/10/03)
Treatment of 7-phenyl-6-heptynal dimethyl acetal with iodotrimethylsilane afforded 2-(1-iodobenzylidene)cyclohexyl methyl ether via the intramolecular nucleophilic attack of the carbon-carbon triple bond to the oxonium ion generated by the action of iodotrimethylsilane.
Domino imine condensation/intramolecular polar [4π+ + 2π]-cycloaddition of anilines and ω-unsaturated aldehydes: A versatile tool for the highly diastereoselective synthesis of 1,2,3,4,4a,9,9a,10-octahydroacridines
Beifuss, Uwe,Gehm, Henning,Herde, Andreas,Ledderhose, Sabine
, p. 468 - 478 (2007/10/03)
The highly diastereoselective synthesis of substituted 1,2,3,4,4a,9,9a,10-octahydroacridines 7, 8 with five stereogenic centers has been achieved by domino imine condensation/intramolecular polar [4π+ + 2π]-cycloaddition of anilines 3 and ω-uns
