[shrent]

Hello ! 
 
I'm trying one Michael addition reaction between an acrylate based ester with l-alanine as under.

Ph-CO-CH=CH-COOC2H5  +  H2N-CH(CH3)-COOH  makes :  Ph-CO-CH2-CH(COOC2H5)-NH-CH(CH3)-COOH.
                                                  
But here, the solubility of l-alanine inhibits taking reaction in any solvent like Methanol/ethanol, etc. 

Can you suggest something to perform this reaction like, solvent media, making soluble the l-alanine in any solvent & other reaction conditions ? 



Regards,
SHRENT

[AWK]

Try ester of alanine

[shrent]

I have problem using the ester of l-alanine because, after using this ester, I'm getting COOR group of that ester instead of COOH. Here, COOH group is necessary to be there in my michael adduct as in the next step after this addition, COOH should be there in that next step final product.

Like, after the addition reaction, only reducing the C=O to CH2 & getting the final product as : Ph-CH2-CH2-CH(COOC2H5)-NH-CH(CH3)-COOH

[movies]

Have you tried DMF or DMSO?

[shrent]

No movies ! Unfortunately, I even do not know more about how to perform this reaction.

Can you give some more detail about the experimental conditions ?

BTW, as you suggested, how both these solvents may help in this reaction ? I mean, reason of choice for DMF & DMSO ?

[movies]

I don't have any expertise on the reaction conditions, so I can't really help you there.

DMF and DMSO are dipolar aprotic solvents and are really useful for reaction of very polar organic molecules like amines and acids.

[AWK]

Ester is no problem. Did you heard about protective groups.

N. Azizi, M. R. Saidi, Tetrahedron, 2004, 60, 383-387

[HP]

Yes AWK is right about the useful esterification your aminoacid to make it readily soluble in organic solvents.So you also will avoid the zwiterionic interactions you amacid which by my experience this reaction with water soluble aminoacid aducts lead to loss in reactivity in Michael reaction amines with activated double bond compounds. Reaction conditions i have used are heating at 90C for 24h under stir. Your ester isnt acrylate but seems to be maleic or fumaric acid ester. I have tried similar reaction with maleic acid but the result with colamine wasnt very good which is some strange for me because theres 2 COOH activating bonds...

[shrent]

AWK,

I got this paper of Tetrahedron. What would be your suggetions for this paper ?

As per this, I can do michael addition directly between alanine & the acrylate or here also I have to use the alanine ester ? If ester, then benzyl is necessary ?



Dear HP, my ester is ethyl-3-benzoylacrylate.





shrent,
kmorendha

[shrent]

Dear AWK,

Can you pls reply to my previous query ?

[AWK]

Probably it does not matter which acrylic ester you will use. I recomend t-butyl ester of alanine. I is relatively easy to obtain (you ought to have isobutylene). T-Butyl ester protection group can be very easy removed. In other condition you can selectively remove ethyl group from your acrylate ester.

[shrent]

OKAY  !!