Carborane reactions with

Treatment of a carborane derivative of thiirane with A-bromosuccinimide gives a j3-bromodisulfide (79MI50601). Chlorination of CM-2,3-di-f-butylthiirane by f-butyl hypochlorite proceeded differently to the reaction with chlorine itself (Scheme 41) (74JA3146). 

Cluster expansion reactions with diborane provide an alternative route to intermediate closo-carboranes, e.g. ... 

To conclude, we shall mention some metal-atom reactions with boranes (172) and carboranes (173). When cobalt atoms reacted with pentaboraneO) and cyclopentadiene, a number of new metalloborane clusters were formed (172), two of which were 65115003(17-05115)3 and cyclopentyl-B5H40o2(i7-05H5)3. Possible structures for the former are shown in Fig. 42. The reaction of cyclopentadiene, pentaboraneO), and 2-butyne with cobalt atoms yielded the metallocarborane species illustrated in Fig. 43 (173). 

FftMnOjPS CiiHisBz Reaction with boranes or carboranes ... 

Halide abstraction reactions with these carborane derivatives gives sometimes intermediate products rather than metathesis, as in the reaction of Ag(6,7,8,9,10-Br5CB9H5)(r/2-C7I Ix) with [IrCl(CO)(PPh3)] that yields an Ir—Ag adduct (238),1350 or the reaction of [MoCpI(CO)3] with Ag(CBnH12) which gives (239).I357 135 ... 

The disilanickela complex 21 was also found to be a good catalyst for the dehydrogenative double silylation of aldehydes. The nickel-catalyzed reactions of 1,2-bis(dimethylsilyl)carborane 11 with aldehydes such as isobutyraldehyde, trimethylacetaldehyde, hexanal, and benzaldehyde afforded 5,6-carboranylene-2-oxa-l,4-disilacyclohexane.32 34 36 The dehydrogenative 1,4-double silylation of methacrolein and tram-4-phenyl-3-buten-2-one in the presence of a catalytic amount ofNi(PEt3)4 also took place under similar conditions. In contrast, the reaction of 11 with a-methyl-tran.s-cinnamaldehyde and irans-cinnamaldehyde under... 

Dehydrobenzene or benzyne 158 can be trapped by all manner of species. 1,2-Dehydro-o-carborane 159 has been shown to undergo many of the same reactions as its two-dimensional relative, 1,2-dehydrobenzene. Although dehydroaromatic molecules can be formed in a variety of ways, synthetic pathways to 1,2-dehydro-o-carborane are quite limited. An effective procedure reported so far78 first forms the dianion by deprotonation of o-carborane with 2 equiv. of butyllithium. Precipitated dilithium carborane is then treated with 1 equiv. of bromine at 0°C to form the soluble bromo anion 160. Thermolysis of 160 with anthracene, furan, and thiophene as substrates leads to the adducts 161-164.79 80 1,2-Dehydro-o-carborane reacts with norbomadiene to give both homo 2+4 and 2+2 addition, leading to three products 165-167, in a 7 1 ratio79. An acyclic diene, 2,3-dimethyl-... 

In Olin s attempts to derivatize dilithiated products of o-carborane with chlorosilanes for further reaction with ammonia, it was observed that cyclic compounds, instead of polymers, were produced by the interaction of the substituents on the adjacent carbon atoms in the o-carborane units.11 However, when a linear dimethoxy intermediate of m-carborane was reacted as an equimolar mixture with dichlorosilane in the presence of the catalyst FeCl3, the quantitative evolution of CH3C1 was observed... 

The ubiquitous hydrosilation reaction, popular especially in silicone manufacturing,132 has been utilized by Houser and Keller for the synthesis of the networked polymers (104) (Fig. 64) from the reaction of the l,7-bis(vinyltetramethyldisiloxyl)-w-carborane monomer with the polymeric crosslinker, poly(methylhydrosiloxane).133 The reactions were catalyzed by the Speier s catalyst, H2PtCl6. Three samples were... 

The polymer-supported o-carborane, 143, was utilized further for cage decapitation, deprotonation, and reaction with ZrCl4 2THF to generate a polymer-supported... 

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