Complexes of the Lewis Acid Ga[N(C6F5)2]3 with Acetonitrile and Pyridine

The Field of Main Group Lewis Acids and Lewis Superacids: Important Basics and Recent Developments

“…This is due to the much larger steric demand of Py upon complexing with such bulky LA as 60 , which is also reflected in much larger (by 35 kJ mol −1 ) reorganization energy of Ga{N(C 6 F 5 ) 2 } 3 upon complex formation with pyridine. The reorganization energy of Ga{N(C 6 F 5 ) 2 } 3 upon complex formation with acetonitrile is by 28 kJ mol −1 larger than 21 kJ mol −1 for Ga(C 6 F 5 ) 3 [69] which indicates that additional stabilization of free Ga{N(C 6 F 5 ) 2 } 3 decreases its Lewis acidity and results in moderate dissociation enthalpy of 80 kJ mol −1 for Ga{N(C 6 F 5 ) 2 } 3 ⋅ MeCN [170] …”

“…[168] Formation of complexes of 60 with acetonitrile and pyridine in solution was established by NMR spectroscopy. [170] Computational studies at M06-2X/6-311 + + G(2d,2p) level of theory indicate that despite shorter GaÀ N DA bond in complex with acetonitrile (2.017 Å, experimental value for the solid 42 • MeCN 2.005(5) Å [168] ) compared to pyridine (2.080 Å), the computed dissociation energies are 80 and 112 kJ mol À 1 , respectively. This is due to the much larger steric demand of Py upon complexing with such bulky LA as 60, which is also reflected in much larger (by 35 kJ mol À 1 ) reorganization energy of Ga{N(C 6 F 5 ) 2 } 3 upon complex formation with pyridine.…”

“…The reorganization energy of Ga{N(C 6 F 5 ) 2 } 3 upon complex formation with acetonitrile is by 28 kJ mol À 1 larger than 21 kJ mol À 1 for Ga(C 6 F 5 ) 3 [69] which indicates that additional stabilization of free Ga{N(C 6 F 5 ) 2 } 3 decreases its Lewis acidity and results in moderate dissociation enthalpy of 80 kJ mol À 1 for Ga{N(C 6 F 5 ) 2 } 3 • MeCN. [170] The perfluoropyridinoxy group À OC 5 F 4 N was used to create Lewis acid Al(OC 5 F 4 N) 3 by reaction of HOC 5 F 4 N with AlEt 3 in 1,2difluorobenzene. [171] Reaction product is insoluble in fluorobenzene and dichloromethane, suggesting the polymeric nature of the compound in the solid state.…”

“…Formation of complexes of 60 with acetonitrile and pyridine in solution was established by NMR spectroscopy [170] . Computational studies at M06‐2X/6–311++G(2d,2p) level of theory indicate that despite shorter Ga−N DA bond in complex with acetonitrile (2.017 Å, experimental value for the solid 42 ⋅ MeCN 2.005(5) Å [168] ) compared to pyridine (2.080 Å), the computed dissociation energies are 80 and 112 kJ mol −1 , respectively.…”

Lewis acid–base adducts of Al(N(C6F5)2)3 and Ga(N(C6F5)2)3 – structural features and dissociation enthalpies

“…Single crystals of Ga(N(C 6 F 5 ) 2 ) 3 · t BuNC were obtained by cooling the toluene solution to −30 °C. In case of the other three adducts of Ga(N(C 6 F 5 ) 2 ) 3 , single crystals were grown at room temperature (Ga(N(C 6 F 5 ) 2 ) 3 ·MeCN) 48 or −30 °C (Ga(N(C 6 F 5 ) 2 ) 3 ·THF and Ga(N(C 6 F 5 ) 2 ) 3 ·PMe 3 ) after layering the toluene solutions with hexane. Further characterization of the Ga(N(C 6 F 5 ) 2 ) 3 adducts failed, presumably due to complete or partial loss of the Lewis base during the drying of the compounds in vacuo .…”