Polyboranes synthesis

In principle, several general methods are available for the synthesis of polyboranes and their derivatives, and only three will be discussed in more detail ... 

Poly(bis-alkoxysilylene)s, preferential screw sense, 3, 617 Polyboranes, in subicosahedral and icosahedral carborane synthesis... 

Recently, Wade has pointed out a formal analogy between the electronic structures of carboranes and polyboranes and those of metal carbonyl clusters based on the assumption that certain triangulated polyhedra require the same number of skeletal orbitals whether there are BH or CH units as well as transition metal atoms at their apices (120). This assumption is quite reasonable as the synthesis of a large number of polyboranes and carboranes in which a transition metal atom takes the place of a BH skeletal unit may be carried out (70). 

Remarkable diastereoselectivity has been achieved in the synthesis of dinucleoside methylphosphonates from the reactions of dichloro-(methyl)phosphine with suitably protected nucleosides at low temperatures.Various phosphapolyboranes have been obtained from the reactions of dichloro(methyl)phosphine with polyborane... 

Another method for preparing functional Ziegler-Natta polymers is to use an organoborane mediated synthesis. This method has been extensively studied and reviewed by Chung . The success of this technique results from these factors (a) trialkyl boranes are Lewis acids, which are stable to Z-N catalysts, (b) they are soluble in Z-N (hydrocarbon) solvents, (c) they are remarkably versatile synthons for a variety of functional groups. In this case, borane functional alpha olefin monomers (31) are polymerized to polyboranes which can be hydrolyzed to a variety of functional groups. 

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