Recent results of the searches for Supersymmetry in final states with one or two leptons at CMS are presented. Many Supersymmetry scenarios, including the Constrained Minimal Supersymmetric extension of the Standard Model (CMSSM), predict a substantial amount of events containing leptons, while the largest fraction of Standard Model background events -which are QCD interactions -gets strongly reduced by requiring isolated leptons. The analyzed data was taken in 2011 and corresponds to an integrated luminosity of approximately L = 1 fb −1 . The center-of-mass energy of the pp collisions was √ s = 7 TeV.

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A combined experimental/quantum chemical investigation of the transition metal-mediated dehydrocoupling reaction of H(3)B.NMe(2)H to ultimately give the cyclic dimer [H(2)BNMe(2)](2) is reported. Intermediates and model complexes have been isolated, including examples of amine-borane sigma-complexes of Rh(I) and Rh(III). These come from addition of a suitable amine-borane to the crystallographically characterized precursor [Rh(eta(6)-1,2-F(2)C(6)H(4))(P(i)Bu(3))(2)][BAr(F)(4)] [Ar(F) = 3,5-(CF(3))(2)C(6)H(3)]. The complexes [Rh(eta(2)-H(3)B.NMe(3))(P(i)Bu(3))(2)][BAr(F)(4)] and [Rh(H)(2)(eta(2)-H(3)B.NHMe(2))(P(i)Bu(3))(2)][BAr(F)(4)] have also been crystallographically characterized. Other intermediates that stem from either H(2) loss or gain have been characterized in solution by NMR spectroscopy and ESI-MS. These complexes are competent in the catalytic dehydrocoupling (5 mol %) of H(3)B.NMe(2)H. During catalysis the linear dimer amine-borane H(3)B.NMe(2)BH(2).NHMe(2) is observed which follows a characteristic intermediate time/concentration profile. The corresponding amine-borane sigma-complex, [Rh(P(i)Bu(3))(2)(eta(2)-H(3)B.NMe(2)BH(2).NHMe(2))][BAr(F)(4)], has been isolated and crystallographically characterized. A Rh(I) complex of the final product, [Rh(P(i)Bu(3))(2){eta(2)-(H(2)BNMe(2))(2)}][BAr(F)(4)], is also reported, although this complex lies outside the proposed catalytic cycle. DFT calculations show that the first proposed dehydrogenation step, to give H(2)B horizontal lineNMe(2), proceeds via two possible routes of essentially the same energy barrier: BH or NH activation followed by NH or BH activation, respectively. Subsequent to this, two possible low energy routes that invoke either H(2)/H(2)B horizontal lineNMe(2) loss or H(2)B horizontal lineNMe(2)/H(2) loss are suggested. For the second dehydrogenation step, which ultimately affords [H(2)BNMe(2)](2), a number of experimental observations suggest that a simple intramolecular route is not operating: (i) the isolated complex [Rh(P(i)Bu(3))(2)(eta(2)-H(3)B.NMe(2)BH(2).NHMe(2))][BAr(F)(4)] is stable in the absence of amine-boranes; (ii) addition of H(3)B.NMe(2)BH(2).NHMe(2) to [Rh(P(i)Bu(3))(2)(eta(2)-H(3)B.NMe(2)BH(2).NHMe(2))][BAr(F)(4)] initiates dehydrocoupling; and (iii) H(2)B horizontal lineNMe(2) is also observed during this process.