On the Aminolysis of Bis-Imidoylchlorides of Oxalic Acid. II. Reaction with Aliphatic Diamines and Aminoalcohols

Article abstract of DOI:10.1002/prac.199533701107

The aminolysis of bis-imidoylchloride 1 derived from oxalic acid with several diamines and aminoalcohols was investigated.At room temperature diamines 2 as well as aminoalcohols 7 give mainly the cyclic amidines 3 and mixed amidine-imidates 8 in moderately up to good yields.While cis-1,2-diaminocyclohexane yields at room temperature the bicyclic amidine 3a, the trans isomer reacts to 3b only when heated for several hours.Depending on the conditions, the racemic 1,2-diaminopropane 2h gives derivatives of pyrazine 3h or the open-chain amidine 5 resulting from an oxidative aromatization and subsequent hydrolysis.Histamine 2i and 1,8-diamino-3,6-dioxaoctane 2p react selectively with 1 to seven- respectively twelve-membered heterocycles 3i and 3p.The mixed aliphatic and aromatic diamines 2n, o show an anomalous behaviour leading to 2,2'-bis-chinazolines 3n, o.In comparison with acyclic oxalic amidines the new cyclic derivatives show less molecular dynemic in their nmr spectra.In some cases, a s-trans-arrangement of the amidine substructure was observed.