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Octafluoro‐1, 2‐dimethylenecyclobutane, a Perfluorinated Diene Ligand — Carbonyl(η5‐cyclopentadienyl)(η4‐octafluoro‐1, 2‐dimethylenecyclobutane)manganese The [2+2]‐cycloaddition product of tetrafluoroallene ( 1 ), octafluoro‐1, 2‐dimethylenecyclobutane ( 2 ) reacts with tricarbonyl(η5‐cyclopentadienyl)manganese ( 4 ) replacing two carbonyl ligands to give carbonyl(η5‐cyclopentadienyl)(η4‐octafluoro‐1, 2‐dimethylenecyclobutane)manganese ( 5 ). According to the IR spectrum of 5 , the ligand 2 is a strong π acceptor. Among the less volatile by‐products of the dimerizationof 1 , the hydrolysis product of its trimer could be structurally characterized by X‐ray diffraction as the spirocyclic compound decafluoro‐5‐methylene‐spiro[3.3]heptane‐2‐carboxylic acid ( 3 ). The structure of 5 was also determined by an X‐ray crystal structure determination. 相似文献
253.
Reaction of bisalkylidyne cluster compounds [Fe3(CO)9(μ3‐CR)2] ( 1a—d ) ( a , R = H; b , R = F; c , R = Cl; d , R = Br) with the phosphaalkyne t‐C4H9‐C≡P ( 2 ) yield a single isomer of the phosphaferrole cluster [Fe3(CO)8][CR‐C(t‐Bu)‐P‐CR] ( 3a—d ). However, the three isomeric compounds [Fe3(CO)8][C(OEt)‐C(t‐Bu)‐P‐C(Me)] ( 5a ), [Fe3(CO)8][C(Me)‐C(t‐Bu)‐P‐C(OEt)] ( 5b ), and [Fe3(CO)8][C(OEt)‐C(Me)‐C(t‐Bu)‐P] ( 5c ) are obtained in the reaction of [Fe3(CO)9(μ3‐CMe)(μ3‐C‐OEt)] ( 4 ) with 2 . As the phosphaferroles 3 possess a lone pair of electrons at the phosphorus atom they can act as ligands. [Fe3(CO)8][CF‐C(t‐Bu)‐P‐CF]MLn ( 7a—c ) ( a , MLn = Cr(CO)5; b , MLn = CpMn(CO)2; c , MLn = Cp*Mn(CO)2) were formed from 3b and LnM(η2‐C8H14) ( 6a—c ). The dinuclear cluster [Fe2(CO)6][CF‐CF‐C(t‐Bu)‐PH(OMe)] ( 8 ) was obtained from 3b and NiCl2·6H2O in methanol. The structures of 3a—d , 5a—c , 7b , and 8 have been elucidated by X‐ray crystal structure determinations. 相似文献
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Cycloaddition Reactions of Isocyanides with Bis[tris(trimethylsilyl)methyl]diphosphene The [2 + 1] cycloaddition reactions of isocyanoacetonitrile ( 1 a ), pentacarbonyl(diisocyanomethane)chromium ( 1 b ), and 2,2,2-trifluoroethylisocyanide ( 1 c ) with the diphosphene R–P=P–R (R = C[Si(CH3)3]) ( 2 ) yield the expected diphosphirane imines 3 a – c . All compounds are thermally very stable and show no evidence for a [2 + 1] cycloreversion reaction. The structures of 3 a : triclinic, P 1, a = 918.0(2), b = 1174.7(4), c = 1821.9(5) pm, α = 93.83(2), β = 97.22(2)°, γ = 97.08(2)°, Z = 2, R1 = 0.069; 3 c : monoclinic, P21, a = 928.6(2), b = 1659.8(3), c = 1261.2(3) pm, β = 107.65(2)°, Z = 2, R1 = 0.073, and 1,2-Bis[tris(trimethylsilyl)]methyl-N-trifluormethyl-3-diphosphiranimin: monoclinic, P21/n, a = 1374.6(3), b = 1685.9(1), c = 1658.6(5) pm, β = 108.99(9)°, Z = 4, R1 = 0.092, were elucidated by X-ray crystallography. All three compounds possess a similar three membered PCP ring system with an exocyclic C–N double bond. 相似文献
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Lentz D Bach A Buschmann J Luger P Messerschmidt M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(20):5059-5066
Crystals of various fluorinated ethenes were grown by in situ crystallization from their melts on a diffractometer, allowing the structures of tetrafluoroethene (C2F4), trifluoroethene (C2HF)3, 1,1-difluoroethene (C2H2F2), (E)-1,2-difluoroethene (C2H2F2), and (Z)-1,2-difluoroethene (C2H2F2) to be determined by X-ray crystallography. Unexpectedly, the C=C bond lengths show only small variations arising from fluorine substitution. These findings are supported by ab initio calculations at a DFT level of theory and the results of topological analyses of the experimentally determined and theoretically calculated charge densities. 相似文献
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