Assembling Homometallic Sb6 and Heterometallic Ti4Sb2 Oxo Clusters

• Published in: Inorganic chemistry 2020-05, Vol.59 (10), p.6689-6696
• Main Authors: Ugandhar, Uppara, Navaneetha, Tokala, Ali, Junaid, Mondal, Subrata, Vaitheeswaran, Ganapathy, Baskar, Viswanathan
• Format: Article
• Language: English
• ISSN: 0020-1669; 1520-510X
• DOI: 10.1021/acs.inorgchem.9b03238

Isolation and structural characterization of novel organoantimony­(V)-based oxo clusters are reported. (RSb)4(OH)4(t-BuPO3)6 and (RSb)2(O)­(t-BuPO3H)6 independently in the presence of pyridine under solvothermal conditions afford the hexanuclear organoantimonate clusters [(RSb)6(μ3-O)2(μ2-O)6(t-BuPO3)4], where R = p-i-PrC6H4 (1), p-ClC6H4 (2). Further, reaction of organostibonate phosphonate with Ti­(O i Pr)4 in the presence of pyridine under solvothermal conditions afforded the mixed-metal titanium stibonate hexanuclear clusters [(RSb)2Ti4(μ3-O)2(μ2-O)2(t-BuPO3)4(μ-OCH3)4(OCH3)4], where R = p-i-PrC6H4 (3), p-ClC6H4 (4). Band gap measurements were performed on 1–4. They reveal a remarkable reduction in the band gap on moving from the heavier main-group-based oxo cages (1 and 2) to the titanium-incorporated oxo cages (3 and 4).