Mehrfachbindungen zwischen hauptgruppenelementen und übergangsmetallen

Synthesis and Characterization of Cubane‐Like Cr4E4 (E = S, Se) Clusters − Molecular Structures of (η5‐RC5H4)4Cr4E4 (E = S, R = MeCO, MeO2C, EtO2C; E = Se, R = H)

“…Commercial sulfur powder, selenium powder, and 2,4-dinitrophenylhydrazine were used as received. [η 5 -RC 5 H 4 Cr(CO) 3 ] 2 (where R ϭ Me, [16] MeCO, [12] MeO 2 C, [12] EtO 2 C [13] ), [CpCr(CO) 2 ] 2 Se [18] and [η 5 -MeC(O)C 5 H 4 Cr(CO) 2 ] 2 Se [4] were prepared according to literature procedures. All reactions were monitored by thin layer chromatography (TLC) at intervals.…”

“…[15] When the CrϪCr singly-bonded dimers [η 5 -RC 5 H 4 Cr(CO) 3 ] 2 (8, R ϭ Me; [16] 9, R ϭ EtO 2 C [13] ) were refluxed with an equimolar amount of elemental selenium in THF for 8 h or when the linear complexes [η 5 -RC 5 H 4 Cr(CO) 2 ] 2 Se (10, R ϭ Me; [17] 11, R ϭ EtO 2 C [17] ) were treated with an equimolar quantity of selenium in refluxing THF for 8 h, the corresponding cubane Cr 4 Se 4 clusters 12 and 13 were obtained in excellent yield (see Scheme 3). [4] and its parent complex [CpCr(CO) 2 ] 2 Se (15) [18] were treated with elemental selenium in refluxing THF for 8 h, a series of Cr 4 Se 4 cubane clusters with the general formula [η 5 -MeC(O)C 5 H 4 ] n Cp 4Ϫn Cr 4 Se 4 (16؊20, n ϭ 0Ϫ4) were produced in total 97 % yield (see Scheme 4).…”

Cyclopentadienyl Complexes of Chromium, Molybdenum and Tungsten

“…957 Access to the analogous Cp* chemistry can be gained through reaction o f [Cr(CO) 3 Cp*]~ with trithiazyl chloride (N 3 S 3 C1 3 ). 959 The reaction of [Cr(CO) 3 …”

Synthesis, spectroscopic characterization and reactivities of linear and butterfly chromium/selenium complexes containing substituted cyclopentadienyl ligands: crystal structures of [{η5-MeC5H4Cr(CO)2}2Se] and [{η5-EtO2CC5H4Cr(CO)2}2Se2]

“…Recently, we reported the synthesis of some linear Cr 2 Se and butterfly Cr 2 Se 2 compounds with substituted cyclopentadienyl ligands and their skeleton transformation reactions leading to the corresponding cubane-like Cr 4 Se 4 clusters [5]. As part of this project, we wish to report in this article the synthesis and structural characterization of another new linear Cr 2 Se and butterfly Cr 2 Se 2 complexes [{g 5 -RC 5 H 4 Cr(CO) 2 } 2 Se] and [{g 5 -RC 5 H 4 Cr(CO) 2 } 2 Se 2 ] (R ¼ Me, CO 2 Et, Me-CH(OH), PhCH@CMe, 2,4-(NO 2 ) 2 C 6 H 3 NHN@CMe).…”

“…The linear Cr 2 Se and butterfly Cr 2 Se 2 compounds are of great interest, because of their unique structures, high reactivity and the practical applications as building blocks in synthesis of Cr/Se-containing organometallic and cluster complexes [1][2][3][4]. Recently, we reported the synthesis of some linear Cr 2 Se and butterfly Cr 2 Se 2 compounds with substituted cyclopentadienyl ligands and their skeleton transformation reactions leading to the corresponding cubane-like Cr 4 Se 4 clusters [5].…”