Аннотация:The highly Lewis acidic, cationic aluminum species [DIPP-nacnacAlMe]+[B(C6F5)4]− (1, DIPP-nacnac = [HC{C(Me)N(2,6-iPr2C6H3)}2]−) has been shown to undergo reactions with a wide variety of small molecules, in both the presence and absence of an external weak phosphine base, PPh3. Cycloaddition reactions of unsaturated C–C bonds across the aluminum diketiminate framework are reported, and the first structural confirmation of this type of cycloaddition product is presented. Addition of PPh3 to 1 produces the cationic aluminum phosphine complex [DIPP-nacnacAl(Me)PPh3]+[B(C6F5)4]−, which undergoes fluxional dissociation/coordination of the phosphine in solution. This weak Al–P interaction can be utilized in frustrated Lewis pair type reactions to activate alkenes, alkynes, CO2, propylene oxide, and the C–Cl bonds of CH2Cl2. The CO2 adduct [DIPP-nacnacAl(Me)OC(PPh3)O]+[B(C6F5)4]− undergoes further stoichiometric reduction with Et3SiH to produce an aluminum formate species.
Ключевые слова:Organoboron and organosilicon chemistry, Synthesis and characterization of novel inorganic/organometallic compounds, Crystallography and molecular interactions
