3) The use of FLPs to activate dihydrogen is now well-established. The FLP (2- (bis(perfluorophenyl)boryl)ethyl)dimesitylphosphine easily...

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3) The use of FLPs to activate dihydrogen is now well-established. The FLP (2- (bis(perfluorophenyl)boryl)ethyl)dimesitylphosphine easily activates dihydrogen accordingly (see Scheme 2 of the paper): H₂ Mes2PB(C6F5)2 Mes2 H H B(C6F5)2 Mes = mesityl What is unusual about the intramolecular zwitterion product, specifically the chemical nature of the hydrogens on the phosphorus and boron centres? What kind of bond cleavage is this? Can you draw an analogy to a corresponding metal- catalyzed activation of dihydrogen, specifically within the context of hydrogenation of unsaturated substrates? Scheme 2. FLP Activation of H₂ H₂ Mes₂HP- --B(C6F5)2 Mes₂P H H -B(C6F5)2 Θ PtBuz H₂ PHIBU2 Fe Fe Θ Ph B(C6F5)3 Ph Ph Ph Ph Ph [HB(C6F5)3] Ph Ph Ph Ph B(C6F5)3 -60°C Bu + H₂ ItBu H NH Θ [HB(C6F5)3] H2 N Bu [HB(C6F5)3] N-B(C6F5)3 B(C6F5)3 © H₂ (0-C6H4Me)3P [(0-C6H4Me)3PH] B(p-C6F4H)3 Vac [HB(p-C6F4H)3] 3) The use of FLPs to activate dihydrogen is now well-established. The FLP (2- (bis(perfluorophenyl)boryl)ethyl)dimesitylphosphine easily activates dihydrogen accordingly (see Scheme 2 of the paper): H₂ Mes2PB(C6F5)2 Mes2 H H B(C6F5)2 Mes = mesityl What is unusual about the intramolecular zwitterion product, specifically the chemical nature of the hydrogens on the phosphorus and boron centres? What kind of bond cleavage is this? Can you draw an analogy to a corresponding metal- catalyzed activation of dihydrogen, specifically within the context of hydrogenation of unsaturated substrates? Scheme 2. FLP Activation of H₂ H₂ Mes₂HP- --B(C6F5)2 Mes₂P H H -B(C6F5)2 Θ PtBuz H₂ PHIBU2 Fe Fe Θ Ph B(C6F5)3 Ph Ph Ph Ph Ph [HB(C6F5)3] Ph Ph Ph Ph B(C6F5)3 -60°C Bu + H₂ ItBu H NH Θ [HB(C6F5)3] H2 N Bu [HB(C6F5)3] N-B(C6F5)3 B(C6F5)3 © H₂ (0-C6H4Me)3P [(0-C6H4Me)3PH] B(p-C6F4H)3 Vac [HB(p-C6F4H)3]