N-[2-(4-methoxyphenyltelluro)ethyl]phthalimide (L-1): synthesis, oxidationby ruthenium(III) chloride and ligation with ruthenium(II). Crystal structures of L-1, its oxidized product and of [RuCl2(p-cymene)center dot L-1]

N-[2-(4-methoxyphenyltelluro)ethyl]phthalimide (L-1) synthesized by reactin g ArTe- (generated in situ) with N-(2-bro-moethyl)phthalimide, has been cha racterized structurally. The Te-C(alkyl) (2.147(5) Angstrom) is somewhat lo nger than Te-C(aryl) (2.111(4) Angstrom). The L-1 on reaction with RuCl3. x H(2)O results in a novel heterocycle, Te-chloro,Te-anisyl-1a-aza-4-oxa-3-te llura-1H,2H,4aH-9-fluorenone (1), which is characterized structurally and i s a unique example of a tellura heterocycle containing oxygen as well as ni trogen in the same ring. The oxidation state of Te changes to + IV in the f ormation of 1. The Te-Cl and Te-O bond lengths in 1 are 2.604(2) and 2.038( 4) Angstrom, respectively. The reaction of L-1 with [RuCl2(p-cymene)](2) gi ves [RuCl2(p-cymene). L-1] (2) which is characterized structurally. The Ru- C (av), Ru-CI and Ru-Te bond lengths are 2.192(1), 2.417(1)-2.434(1) and 2. 651(5) Angstrom, respectively. The difference in Te-C(alkyl) and Te-C(aryl) bond lengths is not affected on the ligation of L-1 with ruthenium(II). (C ) 2000 Elsevier Science S.A. All rights reserved.