Reactions of cationic complex [(η5-C5Me5)Re(CO)3I]+ with primary amines leading to cyclic carbamoyl complexes

The reaction of cationic complex [(5-C5Me5)Re(CO)3I]+ with aliphatic and aromatic primary amines unexpectedly produced the chelated carbamoyl species trans-(5:1-C5Me4CH2NRC(O))Re(CO)2(I) (1, R = Me; 2, R = Pr; 3, R = Ph; 4, R = p-tolyl). The 1-coordination of carbamoyl moiety linkages to a methylene group of tetramethylcyclopentadienyl ligand was confirmed by X-ray crystallography of complex 3. All the complexes were isolated as pure samples and fully characterized by IR, 1H and 13C NMR spectroscopies, mass spectrometry and elemental analysis.

Graphical abstractThe reaction of cationic complex [(η5-C5Me5)Re(CO)3I]+ with aliphatic and aromatic primary amines unexpectedly produced the cyclic carbamoyl species trans-(η5:η1-C5Me4CH2NRC(O))Re(CO)2(I) (1, R = Me; 2, R = Pr; 3, R = Ph; 4, R = p-tolyl). The products were fully characterized by spectroscopy. The X-ray structure of 3 confirms the η1-coordination of the carbamoyl moiety to rhenium.Figure optionsDownload full-size imageDownload as PowerPoint slide