Oxy Effects on the Platinum-Catalyzed Carbo- and Oxacyclizations of 2-Oxiranyl-1-(1-oxyalk-2-ynyl)benzenes
作者:Rupsha Chaudhuri、Samir Kundlik Pawar、Kamalkishore Pati、Rai-Shung Liu
DOI:10.1002/adsc.201200187
日期:2012.8.13
We report new platinum-catalyzed protocols for the synthesis of carbocycles and oxacycles from 2-oxiranyl-1-(1-oxyalk-2-ynyl)benzenes. For 1,2,2-trisubstituted epoxides bearing an acyloxy group, their platinum-catalyzed cyclizations proceed through an initial 1,3-acyloxy shift, followed by an intramolecular attack of an allenyl acetate at the carbonyl group, ultimately giving 2-naphthyl ketones through
The Baylis–Hillman acetates in organic synthesis: Unprecedented sodium nitrite induced intramolecular Friedel–Crafts cyclization of secondary nitro compounds
作者:Deevi Basavaiah、Daggula Mallikarjuna Reddy
DOI:10.1039/c4ra03573a
日期:——
Unprecedented sodium nitrite mediated intramolecularFriedel–Craftscyclization of alkyl (E)-2-arylidene-4-nitroalkanoates and (E)-3-arylidene-5-nitroalkan-2-ones derived from Baylis–Hillman acetates, providing a facile protocol for synthesis of naphthalenes, phenanthrenes, and carbazoles has been described.
Process for producing 1,3-naphthalenedicarboxylic acid
申请人:Ogawa Hiroshi
公开号:US20050187403A1
公开(公告)日:2005-08-25
1,3-Naphthalenedicarboxylic acid is produced by oxidizing 1,3-dialkylnaphthalene in a liquid-phase with an oxygen-containing gas in the presence of a C
2
-C
6
lower aliphatic carboxylic acid solvent and a catalyst comprising a heavy metal and a bromine compound. By regulating the ratio of the total number of bromine atoms fed into a reaction system to the total number of 1,3-dialkylnaphthalene molecules fed into the reaction system within a specific range, 1,3-naphthalenedicarboxylic acid is efficiently produced with low costs. Using 1,3-dimethylnaphthalene, as the starting 1,3-dialkylnaphthalene, which is produced by isomerizing dimethylnaphthalenes in a liquid phase in the presence of a catalyst comprising hydrogen fluoride and boron trifluoride together with a C
5
-C
10
alicyclic saturated hydrocarbon having a five-membered or six-membered ring structure, a highly pure 1,3-naphthalenedicarboxylic acid is efficiently produced.
A 1,3-carbonyl shift in the platinum-catalyzed aromatization of 2-epoxy-1-(methoxyalk-2-ynyl)benzenes
作者:Rupsha Chaudhuri、Arindam Das、Hsin-Yi Liao、Rai-Shung Liu
DOI:10.1039/c002660c
日期:——
A platinum-catalyzed reaction involving new aromatization/1,3-carbonyl shift cascade of 2-epoxy-1-(methoxyalk-2-ynyl)benzenes is reported. This skeletalrearrangement is mechanistically significant because it involves a remarkable 1,3-carbonyl shift to complete the aromatization and to regenerate the catalyst.
Pt- and Au-catalyzed oxidative cyclization of 2-ethenyl-1-(prop-2′-yn-1′-ol)benzenes to naphthyl aldehydes and ketones: catalytic oxidation of metal-alkylidene intermediates using H<sub>2</sub>O and H<sub>2</sub>O<sub>2</sub>
作者:Bhanu Pratap Taduri、Shariar Md. Abu Sohel、Hsin-Mei Cheng、Guan-You Lin、Rai-Shung Liu
DOI:10.1039/b700659d
日期:——
2-Ethenyl-1-(prop-2â²-yn-1â²-ol)benzenes was cyclized through catalytic oxidation with PtCl2/CO/H2O and PEt3AuCl/H2O2; the metalânaphthylidene intermediates were identified and oxygenated with water and H2O2, respectively; for the efficiency of cyclization, the Au catalytic system is superior to that of the PtCl2-catalysis because of its compatibility toward diverse alcohol substrates including both internal alkynes and terminal alkynes.