CN102786371A - New method for producing alpha,beta-unsaturated carbonyl compounds by using one-pot condensation reaction - Google Patents

Abstract

The present invention relates to a new preparation method for alpha,beta-unsaturated carbonyl compounds, wherein a carbon-carbon bond connection is established between ketone and aromatic alcohol under an effect of CrO3 through a one-pot reaction, and alpha,beta-unsaturated carbonyl compounds are formed. In the traditional preparation methods, alpha,beta-unsaturated carbonyl compounds are produced by carrying out a Claisen-Schmidt condensation reaction between ketone and aldehyde, and some of the aldehyde is obtained by selective oxidation of alcohols. With the method of the present invention, synthesis steps of alpha,beta-unsaturated carbonyl compounds can be simplified or a selection range of reaction raw materials of alpha,beta-unsaturated carbonyl compounds can be expanded. The reaction steps of the method comprise: slowly adding 1.2 times of CrO3 to 15 times of corresponding ketone (a temperature of 0 DEG C), and then slowly adding 1 time of an aromatic alcohol; carrying out a heating stirring reaction on the resulting mixture for 10 hours at a temperature of 56 DEG C; pouring the reaction liquid into a large amount of water after completing the reaction, and then extracting with ether in three times; and carrying out separation purification on the extraction liquid by using a column separation method or a fractionation method to obtain alpha,beta-unsaturated carbonyl compounds, wherein a yield is 65-98%.

Description

The one kettle way condensation reaction generates α, the novel method of beta-unsaturated carbonyl compound

(1) technical field:

The present invention relates to a kind of new preparation α, the method for beta-unsaturated carbonyl compound is specifically at CrO ₃Effect under, one kettle way condensation reaction takes place between ketone and aromatic alcohol, set up the C-C connection, formed α, beta-unsaturated carbonyl compound.

(2) background technology:

α, beta-unsaturated carbonyl compound are one type of important organic cpds, in industry He in the laboratory, important purposes are arranged all.Such as benzylideneacetone can be used as raw material and the aromatics modifier of floral compound, the coal stain of dyestuffs industries and the brightening agent of electroplating industry of synthetic perfume, and in addition, it also has certain insecticidal activity and expelling parasite effect, can be as the stablizer in the sterilant.Two benzal acetone are important organic synthesis intermediates, can be used for anti-day finished product.Phenyl styryl ketone also is one type of important organism, is used for the synthetic of material such as sweeting agent; Because it has antitumorly, anti-oxidant, character such as bacterinertness also have important use biologically in addition.α under the usual conditions, beta-unsaturated carbonyl compound is prepared by the Claisen-Schmidt condensation reaction.The Claisen-Schmidt condensation reaction is the organic reaction of one type of important growth carbochain, and it is to connect and realize through between aromatic aldehyde that does not contain α-hydrogen and ketone, setting up carbon-carbon bond.The catalyzer of traditional Claisen-Schmidt condensation reaction is acid or alkali, such as NaOH, and Ba (OH) ₂, H ₂SO ₄, H ₃PO ₄Deng, the catalyzer of latest report comprises K ₂CO ₃, HgO, LiI, RuCl ₃, some ionic liquid and water magnalium stone etc.

(3) summary of the invention:

The present invention is at CrO ₃Effect under, one kettle way between ketone and aromatic alcohol, set up the C-C connection, formed α, beta-unsaturated carbonyl compound can shorten α, the synthesis step of beta-unsaturated carbonyl compound or enlarge the range of choice of reaction raw materials.

A kind of new preparation α, the method for beta-unsaturated carbonyl compound, its reactions step is:

1, with 1.2 times CrO ₃Join slowly in 15 times the corresponding ketone (0 ℃), add 1 times aromatic alcohol then slowly.

2, the mixture with gained reacted 10 hours 56 ℃ of heated and stirred.

3, after reaction finishes, (if CrO in the water that the reaction solution impouring is a large amount of ₃Consumption when being 2.4g, in the impouring 100mL water), divide three extractions (if CrO with ether then ₃Consumption when being 2.4g, extract used ether is 50mL at every turn), extraction liquid can separate purification through method or the fractionated method of crossing pillar.

4, a series of ketone of this reaction pair and aromatic alcohol have extensive applicability, can obtain the α that productive rate is 65%-98%, beta-unsaturated carbonyl compound (reaction yield is that the molar weight with the phenylcarbinol that feeds intake serves as with reference to calculating).This reaction synoptic diagram is as shown in Figure 1, and its reactant species and reaction yield are listed in the table one.

Fig. 1: through CrO ₃The one kettle way condensation reaction takes place between pure and mild ketone generate α, beta-unsaturated carbonyl compound

Table one: through CrO ₃The one kettle way condensation reaction takes place between pure and mild ketone generate α, beta-unsaturated carbonyl compound ^a

^aThe mixture of corresponding ketone (0.3mol) and aromatic alcohol (0.02mol) is at CrO ₃React in 56 ℃ of heated and stirred under the effect (0.024mol).It is 90 ℃ that the b productive rate is measured the .c temperature of reaction by GC-MS.

5, for the reaction of phenylcarbinol and acetone, if the condition of reaction is: the acetone of 1 times phenylcarbinol and 27 times in 56 ℃ of back flow reaction 10 hours, can obtain 80% benzylideneacetone and 3% two benzal acetone under the effect of 1.2 times chromium trioxide; If the condition of reaction is: the acetone of 1 times phenylcarbinol and 15 times in 56 ℃ of back flow reaction 10 hours, can obtain 72% benzylideneacetone and 14% two benzal acetone under the effect of 1.2 times chromium trioxide.

6, for the reaction of MIBK and phenylcarbinol, temperature of reaction is 90 ℃, and the reaction times is 6 hours.

7, this reaction has extensive applicability, can obtain having the α such as benzylideneacetone and phenyl styryl ketone of commercial value, beta-unsaturated carbonyl compound, and productive rate is higher.This condensation reaction can take place with the ketone (such as the clauses and subclauses 1,3,5 of table one) of fatty or the ketone of aromaticity (such as the clauses and subclauses 2 and the clauses and subclauses 4 of table one) in phenylcarbinol.Other aromatic alcohol such as p-methoxybenzyl alcohol, to chlorobenzene methanol or furfuralcohol also can with acetone generation condensation reaction (such as table one clauses and subclauses 6,7,8), generate corresponding α, beta-unsaturated carbonyl compound.

Embodiment:

Below in conjunction with instance the present invention is carried out detailed explanation.

Instance 1: system

Be equipped with in flask CrO ₃(2.4g, 0.024mol) join slowly acetone (0 ℃, 0.54mol) in, add phenylcarbinol (0.02mol) then slowly.The mixture of gained was reacted 10 hours 56 ℃ of heated and stirred.Reaction in the water that the reaction solution impouring is a large amount of (100mL water), divides three extractions (extract used ether is 50mL at every turn) with ether after finishing then, and extraction liquid can separate purification through method or the fractionated method of crossing pillar.Can obtain productive rate and be 80% benzylideneacetone.

Instance two: preparation

With in the flask with CrO ₃(2.4g, 0.024mol) join slowly methyl phenyl ketone (0 ℃, 0.3mol) in, add phenylcarbinol (0.02mol) then slowly.The mixture of gained was reacted 10 hours 56 ℃ of heated and stirred.

Reaction in the water that the reaction solution impouring is a large amount of (100mL water), divides three extractions (extract used ether is 50mL at every turn) with ether after finishing then, and extraction liquid can separate purification through method or the fractionated method of crossing pillar.Can obtain productive rate and be 91% phenyl styryl ketone.

Claims (1)

1. new preparation α, the method for beta-unsaturated carbonyl compound is characterized in that:

1, with 1.2 times CrO ₃Join slowly in 15 times the corresponding ketone (0 ℃), add 1 times aromatic alcohol then slowly.

2, the mixture with gained reacted 10 hours 56 ℃ of heated and stirred.

3, after reaction finishes, (if CrO in the water that the reaction solution impouring is a large amount of ₃Consumption when being 2.4g, in the impouring 100mL water), divide three extractions (if CrO with ether then ₃Consumption when being 2.4g, extract used ether is 50mL at every turn), extraction liquid can separate purification through method or the fractionated method of crossing pillar.

4, a series of ketone of this reaction pair and aromatic alcohol have extensive applicability, can obtain the α that productive rate is 65%-98%, beta-unsaturated carbonyl compound (reaction yield is that the molar weight with the phenylcarbinol that feeds intake serves as with reference to calculating).This reaction synoptic diagram is shown in figure one, during its reactant species and reaction yield are listed in the table below.

Table one: through CrO ₃The one kettle way condensation reaction takes place between pure and mild ketone generate α, beta-unsaturated carbonyl compound ^a

^aThe mixture of corresponding ketone (0.3mol) and aromatic alcohol (0.02mol) is at CrO ₃React in 56 ℃ of heated and stirred under the effect (0.024mol). ^bProductive rate is measured by GC-MS. ^cTemperature of reaction is 90 ℃.