Hydroboration and Diboration of Imines

Diboration of Dialkynes with [2]Boraferrocenophanes

“…Additionally, a series of multiplets (4.12À4.63 ppm) is resolved for the protons of the Cp rings. The hydrogen atoms of the spacer unit X are detected as two doublets ( 1 J HÀH = 16 Hz) at 5.85 and 7.60 ppm in the case of the vinylene unit (16) and as two multiplets at 7.57 and 7.59 ppm for the phenylene-bridged complex (17), respectively. The terminal substituents R are represented either by two singlets (14, R = Me: 1.91, 2.39 ppm; 16, R = SiMe 3 : 0.20, 0.33; 17, R = SiMe 3 : 0.15, 0.27 ppm) or by a series of multiplets (15, R = Ph: 6.94À8.18 ppm) in the expected regions.…”

“…In only two decades catalytic diboration has developed into an exceptionally useful pathway toward boron-functionalized compounds. ,− Although most reactions feature alkenes − or alkynes , as substrates, the reaction is not limited to their use. Diazo and carbonyl compounds − and even arynes, allenes, , isocyanides, and carbenoids − can be used analogously, making the transition-metal-catalyzed diboration a very versatile method for the functionalization of unsaturated compounds.…”

A Proton-Switchable Bifunctional Ruthenium Complex That Catalyzes Nitrile Hydroboration

“…6b,c,11,12 Despite significant advances in the reduction of nitriles over the last three decades, there remain challenging selectivity problems. 13 For instance, harsh reductants such as main group hydrides show poor selectivity for nitriles in the presence of carbonylcontaining functional groups, 14,15 while heterogeneous hydrogenation of nitriles is incompatible with functional groups susceptible to hydrogenolysis. 16 Due to the problems associated with reagent compatibility, investigations into catalysts that promote nitrile hydroboration are under active investigation, 11b,17 and bifunctional complexes are uniquely situated for this purpose (Figure 1).…”

“…In contrast to the intense attention paid to the development of proton-responsive hydrogenation catalysts, cooperative activation of weakly nucleophilic B–H bonds to effect polar bond reduction remains relatively unexplored. ,,, Despite significant advances in the reduction of nitriles over the last three decades, there remain challenging selectivity problems . For instance, harsh reductants such as main group hydrides show poor selectivity for nitriles in the presence of carbonyl-containing functional groups, , while heterogeneous hydrogenation of nitriles is incompatible with functional groups susceptible to hydrogenolysis .…”