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Metallaborane
In chemistry, a metalloborane is a compound that contains one or more metal atoms and one or more boron hydride. These compounds are related conceptually and often synthetically to the boranes, boron-hydride clusters by replacement of BHn units with metal-containing fragments. Often these metal fragments are derived from metal carbonyls or cyclopentadienyl complexes. Their structures can often be rationalized by polyhedral skeletal electron pair theory. The inventory of these compounds is large, and their structures can be quite complex. Examples Two simple examples are . The MB4 cores (M = Fe or Co) of these two compounds adopt structures expected for nido 5-vertex clusters. The iron compound is produced by reaction of diiron nonacarbonyl with pentaborane. and cyclobutadieneiron tricarbonyl have similar structures. Metallacarboranes Even greater in scope than metalloboranes are metallacarboranes. These cages have carbon vertices, often CH, in addition to BH and M vert ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dicarbollide
In organometallic chemistry, a dicarbollide is an anion of the formula [C2B9H11]2-. Various isomers exist, but most common is 1,2-dicarbollide derived from ortho-carborane. These dianions function as ligands, related to the cyclopentadienyl anion. Substituted dicarbollides are also known such as [C2B9H10(pyridine)]− (pyridine bonded to B) and [C2R2B9H9]2- (R groups bonded to carbon). Synthesis of dicarbollides Dicarbollides are obtained by base-degradation of 12-vertex dicarboranes. This degradation of the ortho derivative has been most heavily studied. The conversion is conducted in two-steps, first "deboronation" and second deprotonation: :C2B10H12 + NaOEt + 2 EtOH → Na+C2B9H12− + H2 + B(OEt)3 :Na+C2B9H12− + NaH → Na2C2B9H11 + H2 The dianion derived from dicarboranes, [C2B9H11]2-, are nido clusters. Three isomers exist. Most commonly studies is the 7,8-isomer, with two adjacent carbon centers on the rim. 7,9- has non-adjacent carbon centers o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
