Gemma Barberà

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The incorporation of iodine atoms onto the boron vertices of the o-carborane framework causes, according to spectroscopic data, a uniform increase in the acidic character of the C(c)-H (C(c)= cluster carbon) vertices, whereas the incorporation of methyl groups onto the boron vertices of the o-carborane framework reduces their acidity. Methyl groups when(More)
The reaction of 3,4,5,7,8,9,10,11,12-I(9)-1,2-closo-C(2)B(10)H(3) with KOH/EtOH gave a mixture of the boron periodinated [1,2,3,4,5,6,9,10,11-I(9)-7,8-nido-C(2)B(9)H(2)](2-) and the highly iodinated on boron [1,2,4,5,6,9,10,11-I(8)-7,8-nido-C(2)B(9)H(3)](2-) in approximately 50% each. Moreover, 3,4,5,6,7,8,9,10,11,12-I(10)-1,2-closo-C(2)B(10)H(2) was(More)
Boron periodination of o-carborane has been achieved by taking account of the fact that B atoms in the cluster are of two types, i.e., those adjacent to both C atoms and the remainder. The high number of nonequivalent leaving groups opens the possibility through B-C coupling to materials with novel possibilities and to self-assembling due to the enhanced(More)
In this paper, the chemistry of 3-X-1,2-closo-C(2)B(10)H(11) (X = halogen) derivatives is extended. Molecular orbital and (11)B and (13)C NMR calculations on these species are presented. A qualitative interpretation of the (11)B NMR spectra of closo o-carborane derivatives is also provided. The synthesis of 3-X-1-R-o-carborane (X = I, Br and R = Me, Ph)(More)
That methyl groups attached to carbon atoms are electron donors must not be generally assumed. In boron clusters, Me groups on boron are electron withdrawing. At the B3LYP/6-31G* level of theory, it has been proven that the Mulliken charge on each boron after substitution of -H by -Me increases by +0.18 unit. This leads to a high build-up of positive charge(More)
This paper analyses the semantic attributes discourse refer-ents in Catalan Sign Language may have in order to have a corresponding location established in sign space. It is argued that a combination of scope and topicality is required when analysing the correlation between the introduction of entities into the discourse and assigning a spatial location.
The use of nucleophilic and electrophilic processes allow the designed synthesis of several B-iodinated derivatives of o-carborane. Because of the straightforward Pd-catalyzed conversion of B-I to B-C bond with Grignard reagents, such as methylMgBr and biPhenylMgBr, both, symmetrical 3,6-R 2-1,2- closo-C 2B 10H 10 and asymmetrical 3-I-6-Me-1,2- closo-C 2B(More)
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