Lanthanoidkomplexe von 1‐(2‐Propenyl)‐ und 1‐(3‐Butenyl)‐1,4,7,10‐tetraazacyclododecan‐4,7,10‐triessigsäure

η³‐1,4,7,10‐tetraazacyclododecane molybdenum tricarbonyl reacts with allyl bromide and 3‐butenyl bromide in dimethylformamide in the presence of K₂CO₃ yielding 1‐(2‐propenyl)‐1,4,7,10‐tetraazacyclododecane ( 1a ) and 1‐(3‐butenyl)‐1,4,7,10‐tetraazacyclododecane ( 1b ), which on their part react with bromoacetic acid tert‐butyl ester in CH₃CN to give 1‐(2‐propenyl)‐1,4,7,10‐tetraazacyclododecane‐4,7,10‐tris‐acetic acid tert‐butyl ester ( 2a ) and 1‐(3‐butenyl)‐1,4,7,10‐tetraazacyclododecane‐4,7,10‐tris‐acetic acid tert‐butyl ester ( 2b ), respectively. Compounds 2a and 2b are converted into the corresponding acids 1‐(2‐propenyl)‐1,4,7,10‐tetraazacyclododecane‐4,7,10‐tris‐acetic acid ( 4a ) (MPC) and 1‐(3‐butenyl)‐1,4,7,10‐tetraazacyclododecane‐4,7,10‐tris‐acetic acid ( 4b ) (MBC) via the trifluoroacetates 3a and 3b . Sm(NO₃)₃(H₂O)₆, LuCl₃(THF)₃, and TmCl₃(H₂O)₆ react with 4a and 4b forming the lanthanide complexes Sm(MPC) ( 5 ), Lu(MPC) ( 6 ), Tm(MPC) ( 7a ) and Tm(MBC) ( 7b ). The IR as well as the ¹H and ¹³C NMR spectra of the new compounds are reported and discussed.