Synthesis, molecular structure, and thermal chemistry of (.eta.5-cyclopentadienyl)dicarbonylrhenacyclopentane

Syntheses, Structures and Reactivities of [CpTc(CO)3X]+ and [CpRe(CO)3X]+

“…All CH 3 groups are displaced from these planes in a direction away from the rhenium atom with average deviations ranging from 0.05(2) A to 0.26(2) Å. This type of displacement appears to be general in pentamethyl-cyclopentadienyl metal complexes (average deviations ranging from 0.037 to 0.205 Å), [8,10,[17][18][19] with no observable significant statistical variation of the M-C(Cp*) bond lengths.…”

“…60-70 %). [17] Cleavage of [Cp*(CO) 2 Re(µ-CO)Re(CO)(η 2 -CH 3 CϵCCH 3 )Cp*] or reaction of [Cp*(CO) 2 Re = Re(CO) 2 -Cp*] with diethyl fumarate also lead to [Cp*Re(CO) 3 ]. [18] …”

“…The M-C(CO) and C-O bonds lengths are in the expected ranges of 1.95-2.15 and 1.10-1.15 Å for metal carbonyl groups. [8,10,[17][18][19] The M-Cp* (centroid) distances range from 1.939(9) for 2a to 1.960(7) for 2, and might be viewed as almost identical and evidently insensitive to the differing arrangements of the carbonyl and halide basal ligands in the four structures. Examination of the individual M-C bond lengths to the Cp* ligand reveals, however, systematic differences in structures.…”

Photochemical Reactions of [(η5‐C5R5)Re(CO)3] (R = Me or H) with Aryl Halides in Benzene: Stoichiometric Formation of Biphenyl

“…The irradiation was conducted in a quartz tube, which was placed adjacent to the lamp, or in a 5 mm Pyrex NMR spectroscopic tube. Complexes [(η 5 ‐C 5 R 5 )Re(CO) 3 ] (R = H, Me),21 trans / cis ‐[CpRe(CO) 2 X 2 ] (X = Cl, Br),15a,22 trans / cis ‐[CpRe(CO) 2 H 2 ],17a,22 trans / cis ‐[Cp*Re(CO) 2 X 2 ] (X = Cl, Br),15a and trans / cis ‐[Cp*Re(CO) 2 H 2 ]23 were prepared according to literature methods.…”

Synthesis of Cyclopentadienyl‐Based Tricarbonyl Rhenium Complexes and Some Unusual Reactivities of Cyclopentadienyl Substituents

“…Fulvenebased (η 6 -C 5 Me 4 -CH 2 )Re(CO) 2 X (X = Cl, I, Br) species analogous to the proposed intermediate A are known and undergo addition reactions with nucleophiles (e.g., halides, phosphines, or amines). [56,57] Furthermore, an understanding of the mechanism of this reaction would provide insights into the development of direct, target-oriented synthetic procedures for planar chiral Cp-based metal complexes. [54,55] The formation of the rhenium(III) dihydride intermediate D correlates with the previously reported and well-characterized complex Cp*Re(CO) 2 (H) 2 and its conversion to Cp*Re(CO) 3 .…”