423773-86-8Relevant academic research and scientific papers
The synthesis of small azamacrocycles bearing pendant aromatic functionalities
Benniston, Andrew C,Ellis, David,Farrugia, Louis J,Kennedy, Roselyn,Peacock, Robert D,Walker, Sarah
, p. 333 - 342 (2002)
A simple synthetic procedure for the mono- or di-functionalization of tri- and tetra-azamacrocycles with electron rich arenes has been developed. Specifically, 1,4,7-triazacyclononane (tacn), 1,4,7,10-tetraazacyclododecane (cyclen) and 1,4,8,11-tetraazacyclotetradecane (cyclam) react with 2,4,6-trimethylstyrene in the presence of n-butyllithium to give, respectively N-(mesitylethyl)-1,4,7-triazacyclononane (L1), N-(mesitylethyl)-1,4,7,10-tetraazacyclododecane (L4), and N-(mesitylethyl)-1,4,8,11-tetraazacyclotetradecane (L5). In contrast, when styrene itself or p-vinylanisole are used as the Michael acceptor with 1,4,7-triazacyclononane, the N′,N″ product is formed, respectively N′,N″-bis(phenylethyl)-1,4,7-triazacyclononane (L2) and N′,N″-bis(p-methoxyphenylethyl)-1,4,7-triazacyclononane (L3). Using conventional mono-functionalization techniques, the phenyl derivatives N-(4-hydroxymethylbenzyl)-1,4,7-triazacyclononane (L6) and N-(4-benzylcarboxylic acid)-1,4,7-triazacyclononane (L7) have also been synthesised. A series of transition metal complexes of L1 to L7 with Ni(II), Cu(II), Zn(II) and Co(II) have been prepared. The X-ray crystal structures of [Cu(L1)2](PF6)2, [(L1)CuCl2], [Cu(L6)(NO3)2] and [Cu2(L7-H)2(OH2)2] (PF6)2·3H2O are described. In all of these complexes, coordination to the metal takes place through the macrocycle nitrogens. The crystal structure of [Cu2(L7-H)2(OH2)2] (PF6)2·3H2O reveals that it is a coordinate-polymeric material. Attempts to coordinate the pendent arenes to Rh(I) are discussed.
