Three triazacyclononanes bearing pendant alkynyl groups [1,4,7-tri(4-pentynyl)-1,4,7-triazacyclononane (ptacn), 1,4,7-tri(5-phenyl-4-pentynyl)-1,4,7-triazacyclononane (pptacn) and 1,4,7-tri(4-hexynyl)-1,4,7-triazacyclononane (4htacn)] have been synthesized. Seven complexes, [Mo(CO)3(pptacn)], [Rh(cod)(pptacn)][PF6], [RhCl3(pptacn)], [CuCl2(pptacn)], [Ni2(μ-Cl)3(pptacn)2]Cl, [Rh(CO)2(4htacn)][PF6] and [Mo(CO)3(ptacn)], each of which bears three pendant alkynyl groups, have been prepared. Single-crystal structure determinations for [H(4htacn)][BPh4], [Mo(CO)3(pptacn)], [Rh(cod)(pptacn)][PF6] and [CuCl2(pptacn)] are reported.