Aminosilane bearing bulky substituents on nitrogen: LH2 (L = Me2Si(NDipp')2, Dipp = 2,6-diisopropylphenyl) was reacted with BuLi in toluene. The resulting bulky chelating dianion Me2Si(NDipp)2 was used to synt...Aminosilane bearing bulky substituents on nitrogen: LH2 (L = Me2Si(NDipp')2, Dipp = 2,6-diisopropylphenyl) was reacted with BuLi in toluene. The resulting bulky chelating dianion Me2Si(NDipp)2 was used to synthesize the unusual spirocyclic heterotriatomic complex [MeESi(NDipp)2]ESn (1) by its reaction with SnCl4 and the bulky heterotriatomic complex Me2Si(NDipp)2SnPh2 (2) with Ph2SnC12. 1 belongs to the monoclinic system, space group P21/n with a = 13.193(2), b = 20.663(3), c = 20.403(3)A, β = 99.954(2)°, V = 5478.3(15) A3, C55H85.5N4Si2Sn, Mr = 977.64, Z = 4, Dc. = 1.185 Mg/m3, μ(MoKa) = 0.547 mm-1, F(000) = 2086, S = 1.000, the final R = 0.0614 and wR = 0.1322 for 14446 observed reflections (1 〉 2σ(I)) and R = 0.0797 and wR = 0.1456 for all data. 2 belongs to the triclinic system, space group P1 with a = 10.36(15), b = 13.204(7), c = 14.363(7) A, a = 90.214(10), β = 106.182(7), y = 109.854(8)°, V = 1764.4(15) A3, C38HsoN2SiSn, M,. = 681.58, Z = 2, Dc = 1.283 Mg/m^3,μ(MoKa) = 0.785 mm-1, F(000) = 712, S = 1.002, the final R = 0.0498 and wR = 0.0955 for 7533 observed reβections (I 〉 2σ(I)) and R = 0.0676 and wR = 0.1018 for all data. In the structure of 1, the tin atom is located in the spirocyclic center of the two fused four-membered SnN2Si rings. The two complexes were characterized by ^1H NMR, elemental analysis, and single-crystal X-ray structural analysis.展开更多
Symmetryandaxialityarethought tobeguides toward the pursuit of high energy barrier and blocking temperature for thedysprosium(Ⅲ)(Dy^(Ⅲ))single-molecule magnets(SMMs).The Dy^(Ⅲ)complexeswith low coordination numbers...Symmetryandaxialityarethought tobeguides toward the pursuit of high energy barrier and blocking temperature for thedysprosium(Ⅲ)(Dy^(Ⅲ))single-molecule magnets(SMMs).The Dy^(Ⅲ)complexeswith low coordination numbers are intended to satisfy axial symmetry.Here,we report four four-coordinate Dy^(Ⅲ)SMMs based on bis(arylamido)dysprosium building block{Dy(N^(RR’))2(μ-Cl)_(2)K}(N^(RR’)={N(SiMe_(3))(C_(6)H_(3)iPr_(2)-2,6)}^(−)),with two strong Dy–N and twoweak Dy–Cl bonds.Through fine-tuning of axial anisotropy,the SMM with the largest N–Dy–N angle of 139.24(15)°displayed magnetic hysteresis with a coercive field(H_(c))of 18.6 kOe at 2 K,which kept opening up to 35 K.Alternating current susceptibility measurement showed that the relaxation energy barrier reached as high as 1578 K,which is among the highest reported Dy^(Ⅲ)SMMs.Ab initio calculations revealed strong anisotropy and crystal-field axiality of the compound,despite the low symmetry,and provided a synthetically workable approach to construct high-performance SMMs useful in applications such as digital processing,transport electronics,quantumcomputing,and ultra-high-density data storage.展开更多
基金supported by the National Natural Science Foundation of China (No.21001016 and 20901009)
文摘Aminosilane bearing bulky substituents on nitrogen: LH2 (L = Me2Si(NDipp')2, Dipp = 2,6-diisopropylphenyl) was reacted with BuLi in toluene. The resulting bulky chelating dianion Me2Si(NDipp)2 was used to synthesize the unusual spirocyclic heterotriatomic complex [MeESi(NDipp)2]ESn (1) by its reaction with SnCl4 and the bulky heterotriatomic complex Me2Si(NDipp)2SnPh2 (2) with Ph2SnC12. 1 belongs to the monoclinic system, space group P21/n with a = 13.193(2), b = 20.663(3), c = 20.403(3)A, β = 99.954(2)°, V = 5478.3(15) A3, C55H85.5N4Si2Sn, Mr = 977.64, Z = 4, Dc. = 1.185 Mg/m3, μ(MoKa) = 0.547 mm-1, F(000) = 2086, S = 1.000, the final R = 0.0614 and wR = 0.1322 for 14446 observed reflections (1 〉 2σ(I)) and R = 0.0797 and wR = 0.1456 for all data. 2 belongs to the triclinic system, space group P1 with a = 10.36(15), b = 13.204(7), c = 14.363(7) A, a = 90.214(10), β = 106.182(7), y = 109.854(8)°, V = 1764.4(15) A3, C38HsoN2SiSn, M,. = 681.58, Z = 2, Dc = 1.283 Mg/m^3,μ(MoKa) = 0.785 mm-1, F(000) = 712, S = 1.002, the final R = 0.0498 and wR = 0.0955 for 7533 observed reβections (I 〉 2σ(I)) and R = 0.0676 and wR = 0.1018 for all data. In the structure of 1, the tin atom is located in the spirocyclic center of the two fused four-membered SnN2Si rings. The two complexes were characterized by ^1H NMR, elemental analysis, and single-crystal X-ray structural analysis.
基金supported by the National Natural Science Foundation of China(21971006)National Key R&D Program of China(2018YFA0306003,2017YFA0206301,and 2017YFA0204903)High-Performance Computing Platform at Peking University.
文摘Symmetryandaxialityarethought tobeguides toward the pursuit of high energy barrier and blocking temperature for thedysprosium(Ⅲ)(Dy^(Ⅲ))single-molecule magnets(SMMs).The Dy^(Ⅲ)complexeswith low coordination numbers are intended to satisfy axial symmetry.Here,we report four four-coordinate Dy^(Ⅲ)SMMs based on bis(arylamido)dysprosium building block{Dy(N^(RR’))2(μ-Cl)_(2)K}(N^(RR’)={N(SiMe_(3))(C_(6)H_(3)iPr_(2)-2,6)}^(−)),with two strong Dy–N and twoweak Dy–Cl bonds.Through fine-tuning of axial anisotropy,the SMM with the largest N–Dy–N angle of 139.24(15)°displayed magnetic hysteresis with a coercive field(H_(c))of 18.6 kOe at 2 K,which kept opening up to 35 K.Alternating current susceptibility measurement showed that the relaxation energy barrier reached as high as 1578 K,which is among the highest reported Dy^(Ⅲ)SMMs.Ab initio calculations revealed strong anisotropy and crystal-field axiality of the compound,despite the low symmetry,and provided a synthetically workable approach to construct high-performance SMMs useful in applications such as digital processing,transport electronics,quantumcomputing,and ultra-high-density data storage.