- Conversion of 2-alkylcinnamaldehydes to 2-alkylindanones via a catalytic intramolecular Friedel-Crafts reaction
-
(Chemical Equation Presented) The preparation of indanones by the intramolecular acylation of 3-arylpropanoic acids or halides requires the use of non-catalytic acid promoters. In the presence of 5-10 mol % FeCl3, in situ generated dimethyl acetals of (E)-2-alkylcinnamaldehydes cyclize to 1-methoxy-2-alkyl-1H-indenes in good-to-high yields. The 1-methoxyindenes were converted in high yield into 2-alkylindanones by treatment with triethylamine, to effect isomerization to the isomeric enol ethers, followed by acid-catalyzed hydrolysis. Thus, a catalytic, intramolecular Friedel-Crafts reaction leading to 2-alkylindanones from 2-alkylcinnamaldehydes was developed.
- Womack, Gary B.,Angeles, John G.,Fanelli, Vincent E.,Heyer, Christie A.
-
-
Read Online
- Pentamethylphenyl (Ph*) and Related Derivatives as Useful Acyl Protecting Groups for Organic Synthesis: A Preliminary Study
-
A study of acyl protecting groups derived from the Ph? motif is reported. While initial studies indicated that a variety of functional groups were not compatible with the Br 2-mediated cleavage conditions required to release the Ph? group, strategies involving the use of different reagents or a modification of Ph? itself (Ph*OH) were investigated to solve this problem.
- Cheong, Choon Boon,Frost, James R.,Donohoe, Timothy J.
-
p. 1828 - 1832
(2020/10/06)
-
- α-alkylation of ketones by trialkylamines under heterogeneous Pd/C catalysis
-
Ketones are regioselectively α-alkylated with trialkylamines in toluene at 120 °C in the presence of Pd/C.
- Yoon, Il Chul,Kim, Tae Gyun,Cho, Chan Sik
-
p. 1890 - 1892
(2014/05/06)
-
- Indanones and indenols from 2-alkylcinnamaldehydes via the intramolecular friedel-crafts reaction of geminal diacetates
-
(Figure Presented) When treated with Ac2O at rt in the presence of 4-6mol% FeCl3, 2-alkylcinnamaldehydes are converted to 2-alkyl-1H-inden-1-yl acetates through the intermediacy of gem-diacetates. Methanolysis of the indenyl acetates
- Womack, Gary B.,Angeles, John G.,Fanelli, Vincent E.,Indradas, Brinda,Snowden, Roger L.,Sonnay, Philippe
-
experimental part
p. 5738 - 5741
(2009/12/06)
-
- Synthesis and stereochemical aspects of 2,6-disubstituted perhydroazulenes - Core units for a new class of liquid crystalline materials
-
A novel approach for the synthesis of cis/trans-fused perhydroazulenes 13-19 is reported. The stereochemistry of the derivatives of carbene addition products 9a-c/20-22, of the 2,6-disubstituted perhydroazulenes 12a-c/23-25, and that of compounds 26-27 has been studied by single-crystal X-ray crystallography. The hydrogenation of the tropylidene to the perhydroazulene skeleton under various conditions is described. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
- Hussain, Zakir,Hopf, Henning,Pohl, Ludwig,Oeser, Thomas,Fischer, Axel K.,Jones, Peter G.
-
p. 5555 - 5569
(2008/02/04)
-
- Friedel-crafts cyclization of 1,1-difluoroalk-1-enes: Synthesis of benzene-fused cyclic ketones via α-fluorocarbocations
-
1,1-Difluoroalk-1-enes bearing a phenyl group at the C-3, -4, or -5 position, readily obtained from 2,2,2-trifluoroethyl p-toluenesulfonate, are treated with FSO3H·SbF5 to undergo Friedel-Crafts cyclization in (CF3)2CHOH. The cyclization takes place via α-fluorocarbocations, followed by spontaneous hydrolysis of the C-F bond to afford bicyclic ketones including a five, six, or seven-membered ring in good yield.
- Ichikawa, Junji,Jyono, Hideharu,Kudo, Takao,Fujiwara, Masaki,Yokota, Misaki
-
-
- Preparation of acrylophenones and 2-alkyl indanones utilizing hexamethylenetetramine as an inexpensive Mannich reagent
-
Hexamethylenetetramine/acetic anhydride-promoted α-methylenation of aryl alkyl ketones followed by acid-catalyzed cyclization of the resulting acrylophenones produce 2-alkyl indanones in excellent yields.
- Bhattacharya, Apurba,Segmuller, Brigitte,Ybarra, Arnold
-
p. 1775 - 1784
(2007/10/03)
-
- Cobalt-Catalyzed Cyclocarbonylation of Acetylenes under Water Gas Shift Conditions. Selective Synthesis of Indan-1-ones
-
Carbonylation of phenylacetylene derivatives by a cobalt catalyst under water gas shift conditions affords indan-1-ones in satisfactory yields.
- Doyama, Kazuo,Fujiwara, Keisuke,Joh, Takashi,Maeshima, Kazuo,Takahashi, Shigetoshi
-
p. 901 - 904
(2007/10/02)
-