[HP]

Hi alles!
I have this trouble with Mannich type reaction:
It's reaction of amine with formaldehyde and malonic acid
R-NH2 + CH2O + H2C(COOH)2 -->
And i am asking what kind of products possibly obtain this reaction. First i think about Mannich type reaction with the formed imine intermediate
R-N=CH2 + H2C(COOH)2 --> R-NH-CH2-CH(COOH)2
But i think its also very possible Knoewenagel type reaction leading to itaconic acid: H2C=C(COOH)2
Also do you think its possible Michael type adition of the amine to itaconic acid leading to the first described product:
R-NH2 + H2C=C(COOH)2--> R-NH-CH2CH(COOH)2
Thanks for any ideas!

[FeLiXe]

I don't think there is a possibility for Knoevenagel or Michael because it's not an ester. The two carboxylic acid protons are much more acidic.

The Mannich product sounds pretty good. It officially only works with an imminium ion. But I guess the endiol of the malonic acid  is stable enough because of conjugation to make up for that. (Malonic ester is mostly in enole form, no idea if malonic acid makes endiol)

[HP]

Thanks for your reply! I also think Mannich type reaction most possible but wasnt very sure What do you think about thermal stability of the formed Mannich base do you think easy possible this decarboxylation reaction:
R-NH-CH2-CH(COOH)2  heat--> RNHCH2CH2COOH + CO2 ?

[FeLiXe]

I'm pretty sure it decarboxylates as any 3-Oxo-carboxylic-acid if you heat it up in acid conditions.

[HP]

Yah, you right. I dont have practical experience with Mannich reaction but theoretically its described as acid catalized in heating and long reaction time.
Also all the procedures i red described reaction in aprotic media as toluene, THF and some other organic solvents..But my amine is pretty water soluble and i am asking if possible this reaction in aqueous media and what conditions as general
Sorry for the many words and ths for the help