Unequivocal proof of slowed chromium tricarbonyl rotation in a sterically crowded arene complex: an x-ray crystallographic and variable-temperature high-field NMR study of (C6Et5COCH3)Cr(CO)3

1990 ◽  
Vol 112 (1) ◽  
pp. 27-32 ◽  
Author(s):  
Patricia A. Downton ◽  
Bavani Mailvaganam ◽  
Christopher S. Frampton ◽  
Brian G. Sayer ◽  
Michael J. McGlinchey
Keyword(s):  
High Field ◽  
Variable Temperature ◽  
Chromium Tricarbonyl ◽  
X Ray ◽  
Nmr Study ◽  
Arene Complex

Protonation of chromium tricarbonyl complexes of triphenylsilanol and triphenylcarbinol: synthetic, x-ray crystallographic, and NMR study of (Ph3SiOH)[Cr(CO)3]n (n = 1-3) and of (Ph3COH)Cr(CO)3

1993 ◽  
Vol 12 (7) ◽  
pp. 2462-2471 ◽  
Author(s):  
Krisztina L. Malisza ◽  
Lisa C. F. Chao ◽  
James F. Britten ◽  
Brian G. Sayer ◽  
Gerard Jaouen ◽  
...  
Keyword(s):  
Chromium Tricarbonyl ◽  
X Ray ◽  
Nmr Study ◽  
Chromium Tricarbonyl Complexes

High-field NMR study of vertex rotation in (C5HnMe5-n)MCo2(CO)8CR clusters (M = molybdenum, tungsten): x-ray crystal structure of (C5Me5)MoCo2(CO)8CCO2-iso-Pr

1991 ◽  
Vol 10 (7) ◽  
pp. 2362-2370 ◽  
Author(s):  
Karen A. Sutin ◽  
Lijuan. Li ◽  
Christopher S. Frampton ◽  
Brian G. Sayer ◽  
Michael J. McGlinchey
Keyword(s):  
Crystal Structure ◽  
High Field ◽  
X Ray ◽  
Nmr Study

An x-ray crystallographic and high-field NMR study of chromium complexes [(C6Et6)Cr(CO)2NO]+BF4- and [(C6Et6)Cr(CO)(CS)NO]+BF4-: steric inhibition of tripodal rotation

1991 ◽  
Vol 113 (4) ◽  
pp. 1177-1185 ◽  
Author(s):  
Bavani Mailvaganam ◽  
Christopher S. Frampton ◽  
Siden Top ◽  
Brian G. Sayer ◽  
Michael J. McGlinchey
Keyword(s):  
High Field ◽  
Chromium Complexes ◽  
X Ray ◽  
Nmr Study

Variable temperature 13C NMR study of some L(CO)3FeH(SiR3) (L = CO, P(OPh)3; R = Ph, Me, Cl) species. X-ray crystal structure of P(OPh)3(CO)3Fe(H)SiPh3

Polyhedron ◽  
1991 ◽  
Vol 10 (8) ◽  
pp. 841-849 ◽  
Author(s):  
John W. Connolly ◽  
Michael J. Hatlee ◽  
Alan H. Cowley ◽  
Paul R. Sharp
Keyword(s):  
Crystal Structure ◽  
13C Nmr ◽  
Variable Temperature ◽  
X Ray ◽  
Nmr Study

Addition of Alkynes to the Metal-Metal Double Bond in (η-C5Me,5)2Rh2(µ-CO)2; Crystal and Molecular Structure of the Complex (η-C5Me5)2Rh2(µ-CO){µ-C(O)C2(CF3)2}.

1985 ◽  
Vol 38 (2) ◽  
pp. 273 ◽  
Author(s):  
RS Dickson ◽  
GS Evans ◽  
GD Fallon
Keyword(s):  
Room Temperature ◽  
Variable Temperature ◽  
Heavy Atom ◽  
The Other ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
X Ray ◽  
Arene Complex ◽  
Metal Metal ◽  
Rhodium Atom

Various alkynes (EtC2Et, MeO2CC2CO2Me, CF3C2CF3, PhC2Ph, C6F5C2C6F5, PhC2Me, PhC2C6-F5, PhC2CO2Me) react with (η-C5Me5)2Rh2(μ-CO)2 in acetone at room temperature; no reaction was observed with ButC2But. The σ-bridging alkyne complex, trans-(η-C5Me5)2Rh2(CO)2(μ-η1:η1C6F5C2C6F5), was obtained from the reaction with C6F5C2C6F5. With the other alkynes, dimetallaeneone complexes, (η-C5Me5)2Rh2(μ-CO){μ-η2:η2-C(O)C2RR′}, are formed. Some of these 'eneone' complexes co-exist with (η- C5Me5)2Rh2(CO)2(μ-η1:η1-RC2R�) in the solid state (RC2R� = PhC2C6F5) and/or in solution (EtC2Et, CF3C2CF3, PhC2C6F5); others (MeO2CC2CO2Me, PhC2Ph, PhC2Me, PhC2CO2Me) exist exclusively as (η-C5Me5)2Rh2(μ-CO){μ-η2:η2- C(O)C2RR′} in both the solid and solution states. The geometry of the bridging group in (η-C5Me5)2Rh2(μ-CO){μ-η2:η2-C(O)C2(CF3)2} has been determined from an X-ray diffraction study. The compound crystallizes with four molecules in the monoclinic space group P21/n in a unit cell of dimensions a 9.451(4), b 15.287(5), c 18.821(8)Ǻ, β 98.66(5)°. The structure was solved by conventional heavy atom methods and refined to R 0.066 based on 4356 observed reflections above background. The structure contains a metalla-eneone ring, Rh -C(=O)-C(CF3)=C(CF3), with the alkene bond η2-attached to the second rhodium atom. Variable temperature N.M.R . measurements establish that the complexes (η- C5Me5)2Rh2(μ-CO){μ-η2:η2-C(O)C2R2}(R = CF3 or CO2Me) are fluxional in solution. Facile cleavage of a C(O)-C(R) bond enables the metalla-eneone ring to shift rapidly from one rhodium atom to the other. Other products formed in the reactions between (η-C5Me5)2Rh2(μ-CO)2 and RC2R′ include. (η-C5Me5) Rh {C4(CF3)4CO}, (η-C5Me5) Rh (η4-C6R6) (R = CF3 or CO2Me), (η-C5Me5)2Rh2-(C4R2R′2) (R = R′ = CO2Me; or R, R′ = Ph, C6F5), (η- C5Me5)2Rh2(CO2C2Ph2), (η-C5Me5)- Rh (C4Ph4CO2), (η-C5Me5)2Rh2(CO)2{C4(CF3)4}, (η-C5Me5)2Rh2(CO)(μ-CO){COC4(C6F5)4} and C6R3R′3 (R = R′ = Ph or CO2Me; R = Ph and R′ = Me). Reactions between (η-C5Me5)2-Co2(μ-CO)2 and alkynes at room temperature or above yield mononuclear cyclopentadienone complexes (η-C5Me5)Co{C4R4CO}(R = Me, CF3 or C6F5), and the mononuclear arene complex (η-C5Me5)Co{C6(CF3)6}.

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