Instead of chloroform use DMSO, especially if its a Robinson annulation
As Tapas has said, chloroform or dichloromethane are not normally suitable solvents for an aldol condensation because the C-Cl bond in these solvents will be subject to nucleophilic substitution and hence the solvent will compete with your aldehyde/ketone for the nucleophile you generate from the base deprotonation of your carbonyl. In addition if you are using NaOH or KOH as your deprotonating base, chloroform will give appreciable quantities of chlorocarbene as Shiv has stated.
I think you should consider suggestions earlier suggestions. However, if you want to change solvent due to restricted availability of EtOH, you could go for MeOH as alternative solvent.
Did u do acid workup after reaction in EtOH? If yes, you might have got dehydrated product ( α,β-unsaturated carbonyl compound) which forms cis and trans isomers. So you might have seen two products on TLC.
chloroform is not a better choice of solvent.
In any case what is really the problem you are having with the use of conventional alcohol because this will help us suggest an alternative solvent.
Dear vathan, i did the work up procedure once the reaction complete. it form two different product one are soluble in ethyl acetate and acetone while the other is soluble chloroform. Afterwards i left both for recrystallization. I ran ftir for both compound and both gave different spectra.
Dear David, the reason i changed to chloroform is due to the high moisture content of the ethanol used. so i figured maybe changing the solvent may help.
Generally this would indicate that you have only partial dehydration of your aldol product, although other side products are possible. It is difficult to establish without structural information.
If you desire the dehydrated product you may need to alter your work up conditions.
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