J1-0972 — Annual report 2009
1.
Diastereoselective synthesis of dimethyl 1-aryl-6´-benzoyl-4a´-methyl-5-oxo-hexahydrospiro[pyrazole-4,7´-pyrrolo[3, 4-c]pyridazine]-dicarboxylates.

Methyl (Z)-2-(benzoylamino)-3-(dimethylamino)propenoate reacts with trimethylenemethane to give methyl (Z)-2-[benzoyl-(2-methylallyl)amino]-3-(dimethylamino)propenoate, from which derivatives of pyrazole by substitution of dimethylamino group with hydazine and cyclization with ester group are formed. In the reaction of pyrazoles with 1,2,4,5-tetrazine-3,6-dicarboxylate diastereoisomeric 1-aryl-6´-benzoyl-4a´-methyl-5-oxo-hexahydrospiro-[pyrazol-4,7´-pyrrolo[3,4-c]pyridazine]-dicarboxylates are formed. This transformation represens a simple method for preparation of new heterocycles.

COBISS.SI-ID: 30103557
2.
[2+2] Cycloadditions of electron-poor acetylenes to (5Z)-5-[(dimethylamino)methylene]imidazolidine-2,4-diones

[2+2] Cykloadditions of 2-amino-3-dimethylaminopropenoates with acetylenecarboxylates under microwave irradiation are described. Polyfunctional derivatives of 1-amino-4-(dimethylamino)buta-1,3-dienes are formed in one isomeric form. Furthermore, [2+2] cycloadditions of acetylene mono in dicarboxylates to (5Z)-5-[(dimethylamino)methylene]imidazolidine-2,4-dione and to the corresponding tiooxo derivates under microwave irradiation were also studied. In acetonitrile polyfunctional derivatives of imidazolidine-2,4-diones were produced, while in DMF partial was observed.

COBISS.SI-ID: 30316805