Reactions of Cu(i)Br with aziridine derivatives. Synthesis, characterization and crystal structures of monomeric, dimeric and hexameric aziridine (= az) complexes of the formal type [CuBr(az)2]n (n = 1, 2) and [CuBr(az)]6

Abstract

The first syntheses of monomeric and oligomeric aziridine complexes of copper(I) are described. Cu(I)Br (1) reacts with a series of different aziridine derivatives (C(2)H(3)PhNH (2), C(2)H(2)Me(2)NH (3), C(2)H(2)Me(2)NC(2)H(2)Me(2)NH(2) (4)) to give the neutral dimeric complex [CuBr(C(2)H(3)PhNH)(2)](2) (5) and the ionic hexameric complex [Cu(6)Br(5)(C(2)H(2)Me(2)NH)(6)]Br (6) with terminal bound aziridine ligands as well as the neutral monomeric complex [CuBr(C(2)H(2)Me(2)NC(2)H(2)Me(2)NH(2))] (7) where the dimerized aziridine acts as a N,N'-chelating ligand. After purification, all of the complexes were fully characterized and their IR, (1)H and (13)C NMR spectra are reported and discussed. The single crystal structure analysis revealed distorted tetrahedral geometry for the copper(I) centres in the complexes 5 and 6 and a trigonal planar structure for complex 7. In the oligomers the copper centres are bridged by two μ(2)- (5) or two μ(3)- and three μ(4)-bromido ligands (6), respectively.

Synthesis of chiral 1-(2-aminoalkyl)aziridines via the self-opening reaction of aziridine

“…Transition metal (Cr, Mo, W, Cd, Co)-mediated ring-opening reactions of aziridine ligands yielding aminoethylaziridine-N,N′ complexes by 'aziridine dimerization' were first observed by Beck 24 and Fritz 25 and then by others. 26,27 Recently, synthesis, X-ray structural characterization, antimicrobial and cytotoxic effects of aziridine and 1-(2-aminoethyl)aziridine complexes of Cu(II) and Pd(II) have been reported. 28 Moreover, this transformation can take place spontaneously without Lewis acid in a strongly limited way, when aziridine is stored at room temperature.…”