TY - JOUR
T1 - Synthesis and structural studies of germyl and germyl/stannyl substituted tungstenocenes
AU - Khalimon, Andrey Yu
AU - Dorogov, Konstantin Yu
AU - Churakov, Andrei V.
AU - Kuzmina, Lyudmila G.
AU - Lemenovskii, Dmitry A.
AU - Howard, Judith A.K.
AU - Nikonov, Georgii I.
PY - 2007/6/13
Y1 - 2007/6/13
N2 - One-pot reactions of [WCp2(H)2] and [WCp 2(H)(SnMe3)] with nBuLi followed by an equivalent of GeMe2Cl2 afford mono(germyl) substituted tungstenocenes [WCp2(H)(GeMe2Cl)] (1) and [WCp 2(SnMe3)(GeMe2Cl)] (7). Reactions of the products with tin halides in the presence NEt3 afford the mixed complexes [WCp2(SnR2X)(GeMe2Y)] (X, Y = Cl, Br, RMe, Et), which were further converted to moderately stable compounds [WCp 2(SnR2H)(GeMe2H)] (R = Me (10), Et (11)). A number of asymmetric mono(halo)-substituted germyl/stannyl tungstenocenes [WCp2(SnMe2X)(GeMe2H)] (X = Cl (12), Br (13)) and [WCp2(SnEt2Y)(GeMe2H)] (Y = Br (14), I (15)) were prepared by selective halogenation of the Sn-H bond in 10 and 11. X-Ray studies of [WCp2(H)(GeMe2Cl)] (1), [WCp 2(SnEt2Br)(GeMe2Cl)] (4), and [WCp 2(SnEt2Br)(GeMe2H)] (14) established classical structures of these compounds. X-Ray study of complex [WCp2(SnMe 2Cl)(GeMe2Cl)] (3) revealed the presence of interligand Ge-Cl⋯Sn-Cl interactions in a highly Ge/Sn disordered structure. Analyses of molecular parameters of 1, 4, and 14 suggest the presence of a negative hyperconjugation between metal lone pairs and the σ*-orbital of the E-X bond, which is stronger in bromo substituted complexes in comparison with chloro substituted ones.
AB - One-pot reactions of [WCp2(H)2] and [WCp 2(H)(SnMe3)] with nBuLi followed by an equivalent of GeMe2Cl2 afford mono(germyl) substituted tungstenocenes [WCp2(H)(GeMe2Cl)] (1) and [WCp 2(SnMe3)(GeMe2Cl)] (7). Reactions of the products with tin halides in the presence NEt3 afford the mixed complexes [WCp2(SnR2X)(GeMe2Y)] (X, Y = Cl, Br, RMe, Et), which were further converted to moderately stable compounds [WCp 2(SnR2H)(GeMe2H)] (R = Me (10), Et (11)). A number of asymmetric mono(halo)-substituted germyl/stannyl tungstenocenes [WCp2(SnMe2X)(GeMe2H)] (X = Cl (12), Br (13)) and [WCp2(SnEt2Y)(GeMe2H)] (Y = Br (14), I (15)) were prepared by selective halogenation of the Sn-H bond in 10 and 11. X-Ray studies of [WCp2(H)(GeMe2Cl)] (1), [WCp 2(SnEt2Br)(GeMe2Cl)] (4), and [WCp 2(SnEt2Br)(GeMe2H)] (14) established classical structures of these compounds. X-Ray study of complex [WCp2(SnMe 2Cl)(GeMe2Cl)] (3) revealed the presence of interligand Ge-Cl⋯Sn-Cl interactions in a highly Ge/Sn disordered structure. Analyses of molecular parameters of 1, 4, and 14 suggest the presence of a negative hyperconjugation between metal lone pairs and the σ*-orbital of the E-X bond, which is stronger in bromo substituted complexes in comparison with chloro substituted ones.
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U2 - 10.1039/b618806k
DO - 10.1039/b618806k
M3 - Article
AN - SCOPUS:34250023169
SP - 2440
EP - 2449
JO - Dalton Transactions
JF - Dalton Transactions
SN - 1477-9226
IS - 23
ER -