Ruthenium-Catalyzed Cyclization of Alkyne−Epoxide Functionalities through Alternation of the Substituent and Structural Skeleton of Epoxides
作者:Lin Ming-Yuan、Reniguntala J. Madhushaw、Rai-Shung Liu
DOI:10.1021/jo048983w
日期:2004.10.1
Treatment of 1-(o-ethynylphenyl)-2-alkyl-2-aryl epoxides with TpRuPPh(3)(CH3CN)(2)PF6 catalyst (10 mol %) in hot toluene (100 degreesC, 12 h) led to an atypical cyclization and gave 1-aryl-2-alkyl-1H-indene derivatives and carbon monoxide efficiently. The cyclization of 1-cis-enynyl-2-alkyl epoxides with this catalyst in hot toluene (10 mol %, 100 degreesC, 12 h) gave 2,5-disubstituted phenols in 45-72% yields. Under the same conditions, 1-cis-enynyl-2,2-dialkyl epoxides and 1-cis-enynyl-2-alkyl-2-aryl epoxides gave the corresponding 6,6-disubstituted cyclohexa-2,4-dien-1-ones in good yields (85-91%). Mechanisms for these new cyclization reactions are proposed on the basis of trapping experiments and isotope labeling experiments. The formation of 1H-indene products likely involves ruthenium-acyl intermediates whereas cyclohexa-2,4-dien-1-ones are thought to derive from ruthenium-ketene intermediates.
MIURA, MASAHIRO;NOJIMA, MASATOMO;KUSABAYASHI, SHIGEKAZU;MCCULLOUGH, K. J., J. AMER. CHEM. SOC., 1984, 106, N 10, 2932-2936
作者:MIURA, MASAHIRO、NOJIMA, MASATOMO、KUSABAYASHI, SHIGEKAZU、MCCULLOUGH, K. J.
DOI:——
日期:——
Ozonolysis of a series of 1-substituted indenes. The substituent steric effects on the ozonide exo/endo ratios
作者:Masahiro Miura、Masatomo Nojima、Shigekazu Kusabayashi、Kevin J. McCullough
DOI:10.1021/ja00322a032
日期:1984.5
Ozonolyse d'une serie d'indenes disubstitues (-1,2 et -1,3) et trisubstitues (-1,2,3) dans CCl 4
Ozonolyse d'une serie d'indenes dissubstitues (-1,2 et -1,3) et trisubstitues (-1,2,3) dans CCl 4