The solution dynamics of adduct formationelectronic communication between ligand metal core inelectron deficient quinoline triosmium clusters

Reactions of benzothiazolide triosmium clusters with tetramethylthiourea

“…The molecule contains a triangular cluster of osmium atoms (Os(1)-Os(3) = 2.8581(3), Os(1)-Os(2) = 2.9659 (3) and Os(2)-Os(3) = 2.8948 (4) Å ). One of these distances is slightly shorter and one is slightly longer than average Os-Os bond distance of 2.877(3) Å found in Os 3 (CO) 12 while the other one is substantially longer [30]. Nine linear carbonyl ligands are arranged such that each osmium atom has three.…”

“…This feature may play a key role in the future development of these compounds as catalysts [4][5][6]. We have recently reported synthetic procedures for a novel class of electron-deficient clusters [Os 3 -(CO) 9 (l 3 -g 2 -benzoheterocycle)(l-H)], which result from the reaction of [Os 3 (CO) 10 (CH 3 CN) 2 ] with a wide range of benzoheterocycles followed by thermolysis or photolysis of the initially formed decacarbonyls [7][8][9][10][11][12][13][14][15]. The electron deficiency in these complexes arises from the presence of a three centre two electron bond b to the coordinated pyridinyl nitrogen.…”

“…In comparison with the extensive ruthenium carbonyl cluster chemistry of thiourea ligands only a very limited number of thiourea derived osmium carbonyl cluster compounds have been described in the literature. We [27] and others [28] have reported triosmium clusters containing edge and triply bridging thioureato as well as S-coordinated tetramethyl thiourea ligands from the reactions of the lightly stabilized cluster [Os 3 (CO) 10 (MeCN) 2 ] or [Os 3 (CO) 12 ] with thiourea and tetramethylthiourea. Recently, we have reported the triosmium cluster [Os 3 (CO) 8 (l-dppm)-(l 3 -S) 2 ] containing bridging dppm and capping sulfido ligand from the reaction of [Os 3 (CO) 10 (l-dppm)] with tetramethylthiourea [29].…”

A comparative study of the reactivity of unsaturated triosmium clusters [Os3(CO)8{μ3-Ph2PCH2P(Ph)C6H4}(μ-H)] and [Os3(CO)9{μ3-η2-C7H3(2-Me)NS}(μ-H)] with BuNC

“…On the other hand, the reactions of the electron-deficient benzoheterocyclic triosmium clusters of the type [Os 3 (CO) 9 (l-H)(l 3 -g 2 -L-H)] (L = quinoline, quinoxaline, benzimidazole, benzothiazole, benzoxazole) obtained from decarbonylation of the corresponding decacabonyls [Os 3 (CO) 10 (l-H)(l-g 2 -L-H)], with neutral nucleophiles such as phosphine and amines results in ligand addition at the metal core along with rearrangements whereas reactions with anionic nucleophiles such as hydride or carbanions results in attack at the carbocyclic ring [4][5][6][17][18][19][20]23] (Scheme 2).…”

Water-soluble benzoheterocycle triosmium clusters as potential inhibitors of telomerase enzyme

“…We have recently developed synthetic procedures for a class of benzoheterocycle triosmium clusters of general formula [(l-H)Os 3 (CO) 9 (L)(l 3 -g 2 -(Q-H))], where L = [P(C 6 H 4 SO 3 Na) 3 ] or [P(OCH 2 CH 2 NMe 3 I) 3 ] and Q = quinoline, 3-aminoquinoline, quinoxaline, phenanthridine [23][24][25][26][27][28][29][30] (Fig. 2).…”