LUO Xinxiang;WEN Ruiming;QU Fanqi;HUANG Xiaoling
Wuhan University Journal of Natural Sciences,2006年(3):691-693 ISSN：1007-1202
[LUO Xinxiang; WEN Ruiming] Department of Chemistry and Environmental Engineering, Hunan City University, Yiyang Hunan, China;[QU Fanqi; HUANG Xiaoling] College of Chemistry and Molecular Sciences, Wuhan University, Wuhan Hubei, China
Department of Chemistry and Environmental Engineering, Hunan City University, China
Four novel bridged dianilines containing fluorine were synthesized using 4-chloro-3,5-dinitrobenzotrifluoride and diamine by two step condensation and reduction. The structures of corresponding compounds were determined by means of IR, NMR and elemental analysis.
SOLVENT-FREE;REACTION;solid;base;mixture;catalysis;CHEMOSELECTIVITY;aldehyde-ketone;REACTION;solvent-free reaction;solid base mixture catalysis;chemoselectivity;aldehyde-ketone reaction
Solvent-free reactions of aromatic aldehydes with three representative ketones,including acetophenone,acetone and cyclohexanone,have been examined under the catalysis of a low-cost inorganic base system consisting of NaOH and K2CO3.It was found that the chemoselectivity of the reactions is in close relationship with the composition of the reactants and the doublecomponent catalyst.Under the optimized experimental conditions,1,2,3,4,5-pentasubstituted cyclohexanols,α,β-unsaturated ketones and Claisen-Schmidt bicondensation products were obtained in high yields.Two Kostanecki’s triketones were separated,The composition and structure were affirmed by X-ray crystallographic analysis.
Benzil is an important photosensitive initiator of organic synthesis intermediates,medicinal intermediates and ultraviolet solidified resin (UVresin),and is usually prepared by oxidizing benzoin, The oxidizers and methods reported are mainly;(PhCH_2Et_3N)~+Br~-/(PhCO)_2O_2/MeCN~,DMSO/(COCL)_2 CH_2CL_2~,CrO_3·CH_3NH_2·HCl/Al_2O_3~, the metallorganic compound~,microwave radiation~,etc.The reaction conditions of some methods are harsh, the toxicity is heavy, the reaction reagent is expensive, the preparation is difficult, the aftertreatment is tedious or the conversion ratio of materials is low.Cupric compound is a kind of weak oxidizer.Up till now there is only the report of oxidizing benzoin with cupric sulfate-pyridine~ with cupric acetate-acetic acid~.This paper studies the problem of oxidizing benzoin by using cupric nitrate, cupric chloride, cupric sulfate,cupric acetate and cupric subcarbonate as oxidizers.The experimental results indicate that these cupric compounds can all oxidize benzoin into benzil in acetic acid solutions, and cupric nitrate is the best one.Its product has these adventages of fine color and luster,high yield, available raw material and simple and easy operation and it has the prospects of being used widely.
In the crystal structure of the title compound, C15H12Cl2O2, the chloro-substituted benzene rings are not parallel; the other rings are nearly parallel and the molecules stack in layers parallel to these rings. There are two molecules in the asymmetric unit.
Acetophenone reacted with a series of aromatic aldehydes with grinding under catalysis of a double-component solid base system consisting of NaOH and K2CO3 to furnish highly chemoselectively 1,2,3,4,5-pentasubstituted cyclohexanols in 80-95% yield, and their composition and structure are identified by spectral technologies and single crystal X-ray diffraction analysis, and a possible mechanism of the formation was suggested. (c) 2006 Elsevier Ltd. All rights reserved.