Products of hydrolysis of (ferrocenylmethyl)trimethylammonium iodide: Synthesis of hydroxymethylferrocene and bis(ferrocenylmethyl) ether

The attempted coupling of (ferrocenylmethyl)trimethylammonium iodide (1) with 1,4,7-(triformyl)-1,4,7,10-tetraazacyclododecane (2) in water led to the formation of the expected compound 1-(ferrocenemethyl)-4,7,10-(triformyl)-1,4,7,10-tetraazacyclododecane (3). In addition, hydrolysis of the ferrocenyl precursor 1 led to the formation of two other known compounds, hydroxymethylferrocene (4) and bis(ferrocenylmethyl) ether (5). An X-ray crystal structure determination of 4 revealed the presence of H-bonding between the hydroxyl groups of one molecule of 4 and the oxygen atom of an adjacent molecule resulting in a left-handed helical chain of molecules lying along the b-axis direction. The O⋯O distances are significantly shorter than those found in previously reported structures of hydroxymethylferrocene derivatives indicative of moderate strength H-bonding interactions. In the structure of 5, the orientation of the ferrocenyl groups are staggered relative to a vector comprising the two carbons of the C–O–C linker.